More power from a THOR 4.6

[intheozone]

Hi guys,

How is the best way to unleash more power from the engine?

I have seen YouTube videos of some nice sounding and powerful p38s. Is it just a case of a better exhaust... If so what mods are needed? What pipe, cat, muffler is required?

What other mods can be made?

[wayneg]

You might have a High comp engine, My new car has, if so you have about 16kw up on normal Oz cars. Would be worthwhile running 98ron when you want more horses. You can now get the ECU chipped if you are flush, see ............
ECU Remap Chipping Bosch Thor Motronic V8 Engine Range Rover P38 Discovery 2 V8 | eBay (http://www.ebay.co.uk/itm/ECU-Remap-Chipping-Bosch-Thor-Motronic-V8-Engine-Range-Rover-P38-Discovery-2-V8-/151317540650?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item233b3a6f2a)

How are you going with my Mass airflow sensor.

[redandy3575]

Hi guys,

How is the best way to unleash more power from the engine?

I have seen YouTube videos of some nice sounding and powerful p38s. Is it just a case of a better exhaust... If so what mods are needed? What pipe, cat, muffler is required?

What other mods can be made?

Exhaust would be the best method if only you could get a twin exhaust all the way back to the cat converter. But the problem you got there is your fuel tank is in the way so you still have to converge the two pipes around the tank. Another way would be side exhaust which would have to be custom made, but would sacrifice ground clearance as the standard exhaust is neatly tucked above the chassis line. Another way would be a Pod air filter in place of the normal one, but again, off road capability is reduced more so when crossing rivers due to possible water ingress.

A real cheap and nasty way is a electronic Turbo system. What's that you may ask? Well it's basically a high powered electric fan housed within a silicon pipe which then fits onto your inlet pipe past the MAF. The system has a power swith wired to your electrical system which can be set up to activate when using above 50% throttle. When running, it pumps cold air ( like a turbo. ) into the manifold at about 2 or 3 bar of pressure, giving your engine more oxygen. But you will need an exhaust to match to make it effective.

[clubagreenie]

Seriously? A garden blower is your solution? Do you know what an air pump capable of 3 bar looks like? It ain't 240v let alone 12v.

[TheTree]

Hi

How long is a piece of string and how deep is your wallet ?

If you want to stay factory then high comp pistons are the easiest way.

Other options,

Electric fan as I have done

Dual exhaust, my local guy quoted about 600 from the cats back and it was both pipes exiting on the drivers side due to lack of access.

ECU remap maybe

Modified Camshaft

Balanced Crank

Flowed heads with enlarged ports

Drop a 5 litre in it :p

"A 5 litre 4,997 cc (304.9 cu in) variant of the Rover V8 was used in two models by British sportscar manufacturer TVR. The bore was 94.0 mm (3.70 in) and the stroke was 90.0 mm (3.54 in). These models, used the 5 litre unit in their top-end specifications. The factory quotes up to 340 bhp (254 kW) and 350 lbf·ft (470 N·m) of torque."

Steve

[benji]

There's a nice 4.8 conversion kit from turner engineering too.

Yours should be around 9:1 compression, but you could always go the 4.0 pistons which is 10.8:1 - or there abouts.

A cam, exhaust, inlet and exhaust porting, and maybe even stage 2 heads would make a huge difference though!



Sent from my GT-I9305T using AULRO mobile app

[Hoges]

You might have a High comp engine, My new car has, if so you have about 16kw up on normal Oz cars. Would be worthwhile running 98ron when you want more horses. You can now get the ECU chipped if you are flush, see ............
ECU Remap Chipping Bosch Thor Motronic V8 Engine Range Rover P38 Discovery 2 V8 | eBay (http://www.ebay.co.uk/itm/ECU-Remap-Chipping-Bosch-Thor-Motronic-V8-Engine-Range-Rover-P38-Discovery-2-V8-/151317540650?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item233b3a6f2a)

How are you going with my Mass airflow sensor.

This is very interesting eBay reference:D
If they really have solved it, then I can understand* why they are charging the price quoted and the rigmarole required to get it done...
* Motronic 5.2 Reprogramming (http://www.318ti.org/notebook/motronic_reprogramming/)

The Motronic system was also on the BMW 318 series in the late 90s... tuners were wanting to improve the obvious flaws in the system so as to go racing. The above explains why it is such a pain to tweak!:mad:

[101RRS]

Yours should be around 9:1 compression, but you could always go the 4.0 pistons which is 10.8:1 - or there abouts.

A standard 4.6 is 8.3:1 - with low compression 4.0 pistons this will go to about 9.1:1 but if you go to this trouble just put in 4.6 High compression pistons in.

Garry

[wayneg]

Inthezone has a late car so it might have a 60d HC engine as opposed to 59d LC.

[101RRS]

Maybe but I understood that 4.0 and 4.6 engines sold in Aust were all low compression but occasionally a HC ringin slipped through. I don't recall Hc being an option but am not sure.

Garry

[Hoges]

I looked at some of the rpm figures quoted in the eBay offering and wondered:eek: I would very much like another ...say 50 bhp but manifested as torque in the 2000 - 3500 rpm range.... I rarely exceed 4000rpm... damned shame the BodyLogic TDV6 conversion kit is so expensive..

[intheozone]

Thanks guys all good information to get my head round.

I think I will start with the exhaust option first. Then depending on how good my tax return is I will think about other options.

Wayne I have your MAF and will try to remember to bring it with me next time I am up your way...
I have once again moved and now live and work down Mandurah way.

[101RRS]

So do you have a low compression or a high compression engine. The CR is stamped above the engine number on the engine number tab on the left hand side of the engine.

Garry

[wayneg]

Maybe but I understood that 4.0 and 4.6 engines sold in Aust were all low compression but occasionally a HC ringin slipped through. I don't recall Hc being an option but am not sure.

Garry

Dont know if you have read any of my posts on my latest P38. Picked it up with a raft of problems. Its an October 2001 build, first registered 2002, Had a look at the engine number after buying and was pleased to find 60D, especially good as its also has sequential LPG. From what I read a good few late cars had a High comp engine, maybe they ran out of Low Comp motors.

[redandy3575]

Seriously? A garden blower is your solution? Do you know what an air pump capable of 3 bar looks like? It ain't 240v let alone 12v.

You obviously never seen one let alone experienced one.

[Rabzy]

You obviously never seen one let alone experienced one.

I am very interested in this little mod, could you perhaps shed some more light or some pics for me please?

[DiscoDB]

Google "electric turbo" or "electric supercharger". General consensus is unless they are pulling more amps than your alternator they don't add to the air flow. But it is claimed that there are legit high amp units which can generate a real boost in power for short durations.

[Pedro_The_Swift]

unless you are going to put in tophats, dont spend any money on engine mods.
only two parts of the exhaust are worth worrying about, the manifold to pipe join and the cats,, the rest is fine.

[TheTree]

Hi

I agree you are probably not going to get much more by just doing the exhaust but it will mean future mods should be able to deliver what they promise.

Another thought was to fit an aftermarket ECU like the Haltech then get it on a 4 wheel dyno and tweak it up :p

Steve

[Scouse]

Maybe but I understood that 4.0 and 4.6 engines sold in Aust were all low compression but occasionally a HC ringin slipped through. I don't recall Hc being an option but am not sure.

GarryMost (if not all) 01MY & all 02s had high compression motors.

[redandy3575]

Google "electric turbo" or "electric supercharger". General consensus is unless they are pulling more amps than your alternator they don't add to the air flow. But it is claimed that there are legit high amp units which can generate a real boost in power for short durations.

A lot depends on the engine too, a V8 naturally draws more air than a small 4 cylinder, so an electric turbo will only make a very small difference hence cheap and nasty. But they are not a real turbo in the sense that it actually doesnt compresses the air, its simply a high powered fan in a silicon tube. I had one installed in my 2001 Hyundai Accent past the MAF and the pod air filter and did noticably increase the power slightly along with better response by feeding more oxygen into the engine. More oxygen equals better fuel burn equals more power, simple!! Again on proper turbos you add more fuel as well as the compressed air to give you the bigger boost, but it comes at a high cost.

[DiscoDB]

Interesting article on what Audi are doing with electric turbo's. Clearly not the cheap versions on eBay.

http://www.drive.com.au/motor-news/audi-to-introduce-electric-turbo-in-new-q7-20140615-zs87r.html

[benji]

I'd love to find out the stats on these things; or more importantly understand how they work.

A 4.6 on full song uses just under 11000L of air per minute; which according to one online calculator requires a motor of about 10 horsepower. I wonder how many amps that would require.

Sent from my GT-I9305T using AULRO mobile app

[davidsonsm]

Well ten horses is about 7500watts. Need I go on. 600 amps at 100% efficiency.

[Scouse]

They've been scientifically tested here:
Electric SuperChargers Mythbusted - YouTube (http://youtu.be/cbGWgvJN1_8)

[redandy3575]

They've been scientifically tested here:
Electric SuperChargers Mythbusted - YouTube (http://youtu.be/cbGWgvJN1_8)

Yeah i saw that too.

Two things they are doing wrong. 1.). They incorrectly installed the unit before the air filter which blocks and obstrucks the air flow. It needs to be installed on top of the carby, or at least in a induction tube with a pod filter on the end of it to allow more air to be drawn. Also if an MAF is present, it has to be installed past the sensor, not in front of it.

2.) A matching exhaust system. No point adding all this air when you cannot get rid of it just as quick.

Again, these units are not real compressing turbo chargers, just air boosters giving more oxygen to the motor, and that is where the added power comes from.

[bee utey]

Yeah i saw that too.

Two things they are doing wrong. 1.). They incorrectly installed the unit before the air filter which blocks and obstrucks the air flow. It needs to be installed on top of the carby, or at least in a induction tube with a pod filter on the end of it to allow more air to be drawn. Also if an MAF is present, it has to be installed past the sensor, not in front of it.

2.) A matching exhaust system. No point adding all this air when you cannot get rid of it just as quick.

Again, these units are not real compressing turbo chargers, just air boosters giving more oxygen to the motor, and that is where the added power comes from.
So what you're saying is that you can't notice the effect of one of these hair dryer gadgets unless you do a whole lot of other stuff too? Why not just do the other stuff and save money not buying a tin can fan?

[wayneg]

I have no ideas if these work or not but there are obviously 2 types being punted, most are just fans that will never compress air others use a set up similar to a real Turbo. The most promising looking are DIY efforts using a second hand turbo and a high speed 12v motor to spin it up. These will compress air and have been proven to do so. If they add power is another thing.
I wont be bothering, I am quite content with the Thor 4.6 as it is

https://www.youtube.com/watch?v=rKDYqAoVblM

[DiscoDB]

Stick with the real thing.

http://www.aulro.com/afvb/showthread.php?p=2168333#post2168333

[redandy3575]

So what you're saying is that you can't notice the effect of one of these hair dryer gadgets unless you do a whole lot of other stuff too? Why not just do the other stuff and save money not buying a tin can fan?

That's not what I'm saying. What I am saying is that it needs to be installed correctly to which these clowns on the YouTube clip didn't do. It's no different to a real turbo in the sense that you need to expel the air as quick as you pump into it or else you get a backup of air. These little electronic boosters are basically what a RAM air scoop does but more constantly and stronger. The one I had drew enough air to nearly suck my hand into the fan if I wasn't carefull.

So all I can say is that when I had it installed in my car, it gave it a good 10 - 15% more power, better response ( which is not huge, but then again what do you expect for $180) and improved fuel efficiency. But like I said, it has got to be installed right, or else you're wasting your time.

[redandy3575]

Stick with the real thing.

http://www.aulro.com/afvb/showthread.php?p=2168333#post2168333

Oh definetaly. But it all comes down to how much you want shell out your hard earned.

[TheTree]

HI

I agree with point about the exhaust as I said earlier, that's probably the first thing you should do so that further enhancements will provide maximum benefit.

As to the electric blower, on a small capacity, say 2l, engine I can imagine they provide some benefit but on a 4 to 5 litre V8 a small diameter fan is simply not going to move enough air to make much difference IMO

Steve

[clubagreenie]

I can get a better result from decent CFD on a plenum design and port pulde reversion design/harmonics.

[DiscoDB]

The path for more power from a naturally aspirated petrol motor would always be a performance exhaust system first (tuned headers, twin system, freer flowing), followed by a lumpier cam (preferably a mild cam to keep it drive-able), to then working on getting more fuel in before doing anything involving a complete rebuild.

Then when this is not enough (and it never is), you want some form of forced induction. A sprintex supercharger is probably the least complicated to set up.

The idea of a cheap electric turbo sounds appealing, but when you work out that even the smallest sprintex supercharger needs at least 10kw to drive it you quickly realise that an electric motor driven blower of some sort is going to need to pull some serious amps. As a form of a boost system for short sprints it is feasible, but the elcheapo eBay units pull no where near the amps and hence deliver the compressed airflow needed. You would want get something that is going to pull at least 100 to 200 amps to even start to see some benefit and my guess is when companies like Audi start offering electric turbos their unit will harvest electricity first and then probably have a 400-600 amp motor driving the turbo for short stints when accelerating.

For a small motor, the eBay electric blowers are probably getting more gain from replacing the paper air filter with a low pressure drop foam air filter which give more power if you can add more fuel with the increased air but comes at a cost of reduced filtration.

Anything claiming a few percent improvement you could get the same benefit changing your air filter and engine oil and pumping your tyres up a bit more to reduce rolling resistance.

Now a kit comprising of a hyclone with a foam air filter and an electric turbo and throw in some free fuel magnets - this must be eBay seller heaven! (-;

[clubagreenie]

What if you magnetised the hi-clone?

[Dougal]

What if you magnetised the hi-clone?

You can get the same increase by fitting the hiclone backwards.

[redandy3575]

You can get the same increase by fitting the hiclone backwards.

It's funny you mention that. The electronic booster's fan blade when off creates a similar effect to hiclone as the air rushes through the blades.

[redandy3575]

HI

I agree with point about the exhaust as I said earlier, that's probably the first thing you should do so that further enhancements will provide maximum benefit.

As to the electric blower, on a small capacity, say 2l, engine I can imagine they provide some benefit but on a 4 to 5 litre V8 a small diameter fan is simply not going to move enough air to make much difference IMO

Steve

Oh no doubt the V8 draws more and would need something bigger. The Hyundai that I had was only a 1.5 litre 4 cylinder. I'm certainly not going to bother with my P38. I did find with the snorkel breathing more cooler fresher air did enough to make it run a little better. Might try a RAM head one day to see if it makes a difference.

[Dougal]

It's funny you mention that. The electronic booster's fan blade when off creates a similar effect to hiclone as the air rushes through the blades.

I was however joking. Electric booster fans are a complete waste of time and money.
I'll reconsider my position when you can show me one drawing 300 amps.

[redandy3575]

I was however joking. Electric booster fans are a complete waste of time and money.
I'll reconsider my position when you can show me one drawing 300 amps.

Each to their own I guess. I personally think they do work with the right installation. I think amps has very little to do with it, it's just a power draw.

For example vacuum cleaners. just because you have a 2200watt vacuum cleaner doesn't mean it's going to give you the best suction.

With these boosters it's all about feeding your engine more oxygen, believe it or not, that alone can give you a good 5% increase in power.

[clubagreenie]

Then I'll just hook up a pure O2 bottle to the inlet

[redandy3575]

Then I'll just hook up a pure O2 bottle to the inlet

You can do that too if you wish.

[bee utey]

Each to their own I guess. I personally think they do work with the right installation. I think amps has very little to do with it, it's just a power draw.

For example vacuum cleaners. just because you have a 2200watt vacuum cleaner doesn't mean it's going to give you the best suction.

With these boosters it's all about feeding your engine more oxygen, believe it or not, that alone can give you a good 5% increase in power.
I gather you don't understand that oxygen is a fixed proportion of intake air (around 20%) and no amount of wishful thinking will get substantially more oxygen/air into your motor unless you use substantial amounts of power to do it, ie amps x volts.

And I suppose this thing passes the ol' butt dyno test too, no good doing exhaustive machine tests to see if your fan-in-a-can is worthless, so long as you beliiiieeeve.:p.

[Dougal]

Each to their own I guess. I personally think they do work with the right installation. I think amps has very little to do with it, it's just a power draw.

For example vacuum cleaners. just because you have a 2200watt vacuum cleaner doesn't mean it's going to give you the best suction.

With these boosters it's all about feeding your engine more oxygen, believe it or not, that alone can give you a good 5% increase in power.

I'm guessing you didn't do well in physics at school!

5% is complete fiction. These wastes of time and money will cause more airflow restriction than anything else.

Do you know how much power a supercharger or turbocharger requires to feed an engine?

[Boony73]

Originally Posted by redandy3575 https://www.aulro.com/afvb/images/imported/2016/08/768.jpg (http://www.aulro.com/afvb/p38a-range-rover/199409-more-power-thor-4-6-a-post2169487.html#post2169487)
Each to their own I guess. I personally think they do work with the right installation. I think amps has very little to do with it, it's just a power draw.

As much as I love a good hearty discussion on hiclones and the like I think a little clarification is needed on the high lighted comment.

Power = Amps x Volts

[redandy3575]

I'm guessing you didn't do well in physics at school!

5% is complete fiction. These wastes of time and money will cause more airflow restriction than anything else.

Do you know how much power a supercharger or turbocharger requires to feed an engine?

Dougal, Dougal,Dougal..........:angel WTF

You're spot on. I didn't do well at all at Physics. In fact i completely failed the subject all together:D. Just like you failed mechanics. But one thing is for sure, and if you need physics to work this one out mate, then it's time you went back to school. Oxygen yes is 20% of the air ( thank you Bee utey, you get a pass for that, well done ) but doesn't that make fire aka fuel burn??? ;)
C'MON guys!!!.....seriously!! This isn't rocket science.:angel:

And no Dougal, wrong again!! 5% is not fiction if your engine can breath better, and exhaust better, that is quiet achievable, try it out!! I have.......

Off course superchargers and turbos are much, much , much better, i don't deny that for a second. And at a couple of thousand dollars a piece, it ought to be. What we are talking about is a booster valued at around $180, there's a difference.

Look i'm sorry if some of you don't believe me, and frankly don't really care. But i do know for sure that they do work. Maybe not so much on the bigger motors like the P38s, but on little engines they do work, i know, i've had one. But once more i said it before and i'll repeat it again, it has to be installed correctly, and the power gains are only slight compared to a compressed turbo or a supercharger.

[Dougal]

Dougal, Dougal,Dougal..........:angel:WTF

You're spot on. I didn't do well at all at Physics. In fact i completely failed the subject all together:D. Just like you failed mechanics. But one thing is for sure, and if you need physics to work this one out mate, then it's time you went back to school. Oxygen yes is 20% of the air ( thank you Bee utey, you get a pass for that, well done ) but doesn't that make fire aka fuel burn??? ;)
C'MON guys!!!.....seriously!! This isn't rocket science.:angel:

And no Dougal, wrong again!! 5% is not fiction if your engine can breath better, and exhaust better, that is quiet achievable, try it out!! I have.......

Off course superchargers and turbos are much, much , much better, i don't deny that for a second. And at a couple of thousand dollars a piece, it ought to be.

Look i'm sorry if some of you don't believe me, and frankly don't really care. But i do know for sure that they do work. Maybe not so much on the bigger motors like the P38s, but on little engines they do work, i know, i've had one. But once more i said it before and i'll repeat it again, it has to be installed correctly, and the power gains are only slight unlike a compressed turbo or a supercharger.

Do you sell or have any financial interest in these?

This is physics. I did quite well at physics. Serves me well in my day job. I won't be trying these out. Neither will any of the other people here. You don't need a paint-ball to the nuts to know a paint-ball to the nuts is a dumb idea.
Personally I'd rather invest in a Nigerian lottery win than buy one of your scams.

To get 5% better performance you need 5% better airflow.
To get 5% better airflow through the same engine you need to increase air density by 5%.

To increase air density by 5% you need to compress the air to ~1.4psi.
To compress the air to 1.4psi while feeding a 3.9 litre engine at 3000rpm requires a minimum of 1.5kw worth of compressor power.
1.5kw on a 12V DC system (using 13.8v) is 108 amps.

So there you have it. Compressor power required for a 5% power boost on a 3.9L engine at 3000rpm.
Can this be done by your little fan in a tube? Hell no.

[redandy3575]

Do you sell or have any financial interest in these?

This is physics. I did quite well at physics. Serves me well in my day job. I won't be trying these out. Neither will any of the other people here. You don't need a paint-ball to the nuts to know a paint-ball to the nuts is a dumb idea.
Personally I'd rather invest in a Nigerian lottery win than buy one of your scams.

To get 5% better performance you need 5% better airflow.
To get 5% better airflow through the same engine you need to increase air density by 5%.

To increase air density by 5% you need to compress the air to ~1.4psi.
To compress the air to 1.4psi while feeding a 3.9 litre engine at 3000rpm requires a minimum of 1.5kw worth of compressor power.
1.5kw on a 12V DC system (using 13.8v) is 108 amps.

So there you have it. Compressor power required for a 5% power boost on a 3.9L engine at 3000rpm.
Can this be done by your little fan in a tube? Hell no.

Well good on you Dougal, congrats on passing the subject. I still disagree in you theory there, but that's your opinnion and your're entitled to that.

If you've read my past post, i did say that it wasnt going to be as effective on the V8s. And no i dont have financial interest in the boosters, i just know after having one that they do work OK, need i go on...........??

[clubagreenie]

Internal combustion isn't physics? **** there goes a few degrees I know of and a lot of study I've done.

Can you ID stoimetric ratios?
V/E?
Ever studied CFD of an inlet tract watching pulse reversion and 1st/2nd/3rd/4th order wave harmonics and their effect on reversion and filling/scavenging efficiency?

Come back when you can turn 18k RPM and 880+HP on a stock toyo engine and you've done 5+ years research for it as part of your studies.

Audi were working on reversion theory in the group B days before anyone knew what CFD was, they employed a musical theorist to design their inlets. His background? PHYSICS.

Need you go on? No, but I feel somehow you will.

[Pedro_The_Swift]

did someone say Audi?
Next Audi Q7 to debut with electric turbocharger? - Autoblog (http://www.autoblog.com/2014/06/22/audi-q7-electric-turbocharger-report/)

[Dougal]

Well good on you Dougal, congrats on passing the subject. I still disagree in you theory there, but that's your opinnion and your're entitled to that.

No it's not opinion. It's verified fact.


And no i dont have financial interest in the boosters, i just know after having one that they do work OK, need i go on...........??

How do you know it works OK? How did you test it.


Internal combustion isn't physics?

My sarcasm filter isn't working very well today. I'm not sure which side of the argument you're taking here.

[redandy3575]

How do you know it works OK? How did you test it.



Oh Dougal..........seriously mate, you're starting to troll the forum looking for an argument.

Read the past posts and the answer you're looking for is there. Over out!!

[Dougal]

Oh Dougal..........seriously mate, you're starting to troll the forum looking for an argument.

Read the past posts and the answer you're looking for is there. Over out!!

I have read your posts. There is absolutely nothing there to prove or quantify your claimed results.

[redandy3575]

I have read your posts. There is absolutely nothing there to prove or quantify your claimed results.

Look Dougal let's call it a day. We obviously disagree on the subject and we're not getting anywhere fast. If you want to come over and drive the bloody thing feel free to do so, though it maybe hard condsidering I've sold it. I know it works, and the results speak for themselves and that's where I'm going to leave it. cheers mate.

[DoubleChevron]

Yeah i saw that too.

Two things they are doing wrong. 1.). They incorrectly installed the unit before the air filter which blocks and obstrucks the air flow. It needs to be installed on top of the carby, or at least in a induction tube with a pod filter on the end of it to allow more air to be drawn. Also if an MAF is present, it has to be installed past the sensor, not in front of it.

2.) A matching exhaust system. No point adding all this air when you cannot get rid of it just as quick.

Again, these units are not real compressing turbo chargers, just air boosters giving more oxygen to the motor, and that is where the added power comes from.

A little electric fan will never work. Imagine the air generated by several garden blowers ?? Way more than a piddly little electric fan right?

Leaf-Blower Supercharging a 1978 Chevrolet Monza Spyder! - Roadkill Episode 16 - YouTube

This issue you have is they proved you can increase power and efficency at low revs......... However your "supercharger" :Rolling: Will hugely restrict the intake at higher revs/loads. So you end up losing a lot of power at moderate to high revs due to massive inlet restrictions of the fans, versus a "maybe" tiny gain at very low revs.

Any sort of "fan" will massively loose you power at higher loads/revs IMO ... they'll be worse than magnets tied around your fuel lines. 'cos at least magnets won't restrict the air intake of the motor LOL.

seeya,
Shane L.
PS: If you start watching roadkill, you'll get addicted and end up watching every episode you can find on youtube.

[Hammer H]

Is there anyone out there that has experience with changing the exhaust and cats, that can give recommendations as to best setup (twin/single 2.5 or 3 inch) and any notable improvement in performance.

[redandy3575]

Is there anyone out there that has experience with changing the exhaust and cats, that can give recommendations as to best setup (twin/single 2.5 or 3 inch) and any notable improvement in performance.

I've just had the Catalytics done recently when i replaced the tranny with non-genuine ones from the UK. They're a bit smaller than the originals, but has smoothed out and increased the torque a little as the originals must have been damaged. I was condsidering the complete Magnaflow exhaust with the twin pipes without the rear mufflers to which ive heard a few good reports on. They're dear though!!

[Rabzy]

I really want to no why thay aren't more common, I mean I can go anywhere and get a blower or turbo for a ls v8 but as soon as you mention a rover v8 people go running scared and call the police, is it because the few that we're blown we're done with the wrong size and caused damage, or is it the computer side of things, in which case any other make and model can be done besides range rover?????

[DiscoDB]

I really want to no why thay aren't more common, I mean I can go anywhere and get a blower or turbo for a ls v8 but as soon as you mention a rover v8 people go running scared and call the police, is it because the few that we're blown we're done with the wrong size and caused damage, or is it the computer side of things, in which case any other make and model can be done besides range rover?????

Blowers are a mod people do, it is just turbo's that create issues on lightweight v8's due to handling the heat. Plus don't forget the rover v8 was a built on a hand me down motor from the 60's. For a light motor it was brilliant and worthy of the devotion it gets.

[DiscoDB]

To increase air density by 5% you need to compress the air to ~1.4psi.
To compress the air to 1.4psi while feeding a 3.9 litre engine at 3000rpm requires a minimum of 1.5kw worth of compressor power.
1.5kw on a 12V DC system (using 13.8v) is 108 amps.



At the risk of finding out that perhaps there is some violent agreement taking place here. The original comments offered did say that this could add a benefit to small motors. The calcs above show you could get a marginal benefit on a V8 if you had a system pulling around 100 amps. There are eBay units that pull 120 amps and claim they could add 1.7psi. The maths above shown that we are in the right ballpark for a marginal benefit if set up right. Particularly at low revs.

It is interesting that the Audi article starts with the observation that people see this as a joke. No doubt the Audi system will pull a lot more amps. But the theory is plausible and set up right it it could give a small benefit. Less so for a larger motor but more so at low revs on a small motor.

I still think half the benefit on the eBay units is replacing the air filter with a low flow resistant foam filter as part of the aim is to make it easier to get more air in so you can add more fuel.

I also think as entertaining as this topic has become, I think some chill pills are needed (these also add power if put in your fuel tank - I will be selling these on eBay soon as well!)

(-;

[clubagreenie]

The Audi unit is a low pressure 1st stage unit filling the gap to a 2nd std design turbo.

The Rover has enough head gasket issues lately without adding decomp and turbo's and heat

[Dougal]

The Audi unit is a low pressure 1st stage unit filling the gap to a 2nd std design turbo.

The Rover has enough head gasket issues lately without adding decomp and turbo's and heat

Garrett were publishing research material on an E-booster about 10 years ago. The goal was simply to provide early boost and get the conventional turbo out of bed earlier.
But it's all gone quiet. Looks like their improved VNT turbos and now compound turbo sets provide the low end boost required.

But back to the topic of making them go better.

Compression ratio:
If you pull a lot of torque ratings from different engines and group them by capacity and compression ratio a clear trend emerges. That trend is that peak torque (per litre) is about 10x compression ratio.
Engines with 9:1 compression hover around 90Nm per litre (VE plays the final role), to hit 100Nm/litre you need 10:1 compression (or higher).
So you need to run the highest compression ratio that your normal fuel can sustain.

Air flow:
Surely everyone knows that air flow in a petrol determines fuel fuel which determines power.
Clean up the head ports as much as you can and see what improvements can be made to cylinder fill.

Cams:
Cams can't change the peak torque, but they can move it around the rpm range. If you want to sacrifice some low end torque for high end power then a lumpier cam will do that.

So take a stock 4.6 with about 400Nm at 2,500rpm and 168kw at 4,750 (337Nm).
Bump the compression ratio by 10% will give you about 10% more.
A bit of port and polish might be able to give you another 10% VE at higher rpm.
Pull that off and your previous peak torque can be acheived at 4,750rpm and power becomes ~200kw. Peak torque should now be in the upper 400's.

If you want more than that you'd be into cam changes which will sacrifice low end torque for high end power and drivability might start to suffer.

Excellent table in this link on variations of the engine with torque vs CR: Increasing Capacity (http://www.roversd1.nl/sd1web/capacity.html)

[ohbugger]

Hi guys,

How is the best way to unleash more power from the engine?

I have seen YouTube videos of some nice sounding and powerful p38s. Is it just a case of a better exhaust... If so what mods are needed? What pipe, cat, muffler is required?

What other mods can be made?

Quite a few years ago now, my old man had a pre-update P38 4.6 that he spent quite a bit on. He bought one of the early supercharger kits that had the Eaton unit similar to what was on the V6 Commodes. In a long and drawn out process the get the supercharger working properly there were extensive mods made to the motor itself. A twin exhaust all the way to the rear was made. The heads were ported, larger valves and de-shrouded cleaned up chambers. The intake manifold was extensively modified to create a plenum chamber. Even the block was eventually replaced due the original being pores. Then on-top of all this, a Motec system was employed to run it all. The end result of all this was 188Kw at the wheels.

BUT there were still problems with it. It was found the supercharger was too small for this size motor. Because the supercharger had to be overdriven quite hard, the intake temps were going extremely high very quickly. It was determined that a larger Eaton unit was really needed but the old man didn't want to cut holes in the Rangie to fit that and an intercooler. In the end the supercharger was removed but the rest of the mods remained with the Motec re-tuned to suit. The thing still went way better than stock but without the motor being pulled down all the time.

[davidsonsm]

My newly installed GEMS 4.6 kicks out more power than the original. Was it worth the cost - probably not. There's a noticable improvement, but at the end of the day only a 10% to 20% power increase.

There's the old adage - there's no replacement for displacement. The 5.0L option, with HC pistons sure would be nice. If I was considering a new engine again, I'd buy one off the shelf (from TRS or one of the UK outlets).

Mine has a sleeved block, reworked heads, a mild road cam, HC pistons (about 10.2 is where its ended up), faced heads and a decked block (to optimise the quench gap). Plus a prior twin pipe exhaust and Magnacor ignition leads. Plus all the usual "service" replacement items (no small undertaking when considering oil gears, hoses, belts, water pump, starter motors, seals, gaskets, duplex caliper timing gear, bearings etc).

So from reading this thread, it looks like there is no easy (cost effective) option - other than exhaust and ignition leads.

There were some supercharged (Eaton) P38's available weren't there? I assume they were produced aftermarket by one of the LR specialists (Overfinch or somebody).

[clubagreenie]

I don't know about the displacement argument. I've quadrupled power in engines without touching capacity.

[Dougal]

Displacement is the American's way to increase power. :angel:

[Keithy P38]

Quadruple power without cubes, but tell me how it drives between 1500 and 2500rpm in city traffic!

Someone was saying they had a stock 1UZ-FE rev to 18,000rpm before, that would last about 2 days before friction killed it...

If anyone can even double the stock power between idle and 6,000rpm on a piston motor without losing drivability and fuel "economy" they've won my vote!

Cheers
Keithy

[clubagreenie]

Well it idled at 3200 so driving at 2500 wasn't an issue. That was my UZ also. Wasn't so much friction but keeping oil up to it. As for economy...

But it was still better than the Disco at the moment.

There's a few key things that you'll find in common in all high rpm, high HP engines as well as basic theories on air flow, plenum design, fluid dynamics and harmonics.

[Keithy P38]

Definitely, oiling would be one of the biggest hurdles. Not to mention bearings!

That's a lot of revs hey... I could understand 8,500 from a stock bottom end, but 18,000 is asking for legs out of bed!

[davidsonsm]

I don't know about the displacement argument. I've quadrupled power in engines without touching capacity.
Land Rover obviously followed the displacement path. And when talking about a lazy pushrod V8 conceived in the 1950's, and evolved suit a heavy 4x4, the high reving/highly strung engine discussion isn't really relevant.

[benji]

That reminds me when reading David Hardcastle's book, he was saying how a kiwi bloke in a Morris minor had a 5.5 litre version doing 8000rpm. This was before the serpentine block, but he'd cross bolted the bottom end and such. But David was saying he wouldn't be caught any where near that motor on full song for exactly that 'leg out of bed' reason.

For theories sake, if we leave out the restriction caused by the motor and fan; if the fan can only push 50 percent of the motors requirements, isn't that 50 percent less taxable horsepower on induction; thus a yield of power?

Sent from my GT-I9305T using AULRO mobile app

[Dougal]

If anyone can even double the stock power between idle and 6,000rpm on a piston motor without losing drivability and fuel "economy" they've won my vote!

Cheers
Keithy

Does turbocharging a 4BD1 count?
I hope to double the power of my 4BD1T to approx 200kw. But the air handling side is taking a lot of work to fit under the bonnet while still filtering.

I also keep buying other projects.

[Keithy P38]

It only counts if you put it in a P38 ;-)

I did mean to say "naturally aspirated" also, rookie error!

[clubagreenie]

There's a point where the harmonics in the inlet tract/plenum/runners in conjunction with valve action actually works to make the inlet flow of the air, the filling of the plenum and pressurisation in different areas (in relation to demand requirements) optimised. Without CFD it's VERY theoretical, I read/watched/researched dozens of designs to see what happens. From there just winged it and made a design based on a ferrari v12 H shaped plenum, bellmouths (hand pressed) sized/radiused accordingly etc.

Basically imagine a 2 cylinder log plenum, front inlet) airflow rushing into the back cylinder hits the valve when it closes and the pulse reverts back up the tract and fills the volume and the air is pressurised and there is excess volume for the need of the next cylinder to fill. So front cylinder fills and same events happen. Difference now is the cylinder trying to fill is past the reversion volume. This is where shaping and tapering of the plenum comes into effect.

Now imagine this happening thousands of times per minute and across 4/5/6/8/10/12/16 cylinders. Thats the overly simplified version.

[clubagreenie]

Also to stop the rods throwing reducing rod angle, usually by offset grinding which will reduce capacity but regain through bore and also rod length/pin height. The grinding will reduce the big end size so go all the way to something common (SBC/Honda are good common small sizes). Reduced diameter means less oil shear due to slower speed differential between surfaces.

[Dougal]

It only counts if you put it in a P38 ;-)

I did mean to say "naturally aspirated" also, rookie error!

In Aus a 4BD1T P38 is technically feasible, but I understand not legal. Here's it's legal but we got the 2.5Td so no-one bothers.

[benji]

But those intake harmonics don't travel back beyond the throttle plate do they?
(I'd love to know the intake tuning of the new Nissan v8, a it hasn't got a throttle butterfly, but has variable timing and lift on inlet and exhaust valves).

I would assume the same 'perfect picture' for scavenging exists for the exhaust system too.

But does perfect inlet and exhaust tuning only exist at a certain rev, load point, temperature and humidity? Or can you tune a system to have great scavenging effect over the entire torque range?

Sorry for all the questions; but I find this stuff very interesting.

Sent from my GT-I9305T using AULRO mobile app

[clubagreenie]

It mostly exists inside the plenum as the frequency (valve open/closed rate) is so great that the time doesn't allow it to travel back that far. It works best in a rev range but it's pretty broad.

As for exhausts, there was may hundreds of hours put into each header design, tuned lengths, sequencing collectors. MAKING IT FIT!

[Dougal]

There have been variable length inlet runners in production cars for at least 10 years now. To hit the best cylinder fill at more than one operating point.

But once you use forced induction it all turns to custard. The changing temperature in the inlet tract changes the resonant frequencies and makes tuning for a specific rpm impossible.

[Dougal]

This appears to be the current state of rover V8 tuning to meet UK emissions: Kingsley Cars Limited - 1992 Range Rover 4.8i SE Auto 2 DOOR (http://www.kingsleycars.co.uk/restored-land-rovers/1992-range-rover-3-9i-se-2-door.htm)

Ignore the classic if you must. But the engine is a 4.8L producing 300ft/lb and 265hp. Roughly 400Nm/200kw.

[DANMAL]

I've got a twin 2.5 inch cat back, mild cam (216c ) from memory, top hat liners, in my 99 Thor 4.6 and it really gets up and goes!! Even with the lift and 33 inch BFG mud terrains (didn't even notice any difference in power with the bigger tyres) when I got a comp test done on it at les richmond automotive, all the cylinders were at 170.. they told me that my motor was a high comp.. not sure if that's where all the extra power comes from but hoses down most turbo diesel 4x4s.

[Hammer H]

How is your fuel economy Danmal

[Pedro_The_Swift]

I would think its abysmal,, I know mine is.

[DANMAL]

How is your fuel economy Danmal

usually sits round 14 -17L in city depends on traffic, and 11-15L on freeway.

Cheers Sam

[DANMAL]

I would think its abysmal,, I know mine is.

??...

[TheTree]

Hi

The old fuel consumption thread :o

I have replaced my MAF, O2 sensors and fuel pump but am still getting around 18l / 100k :angry:

Next step is to replace the coolant temp sensor because a failing one of these can cause high fuel consumption and mine is reading 3-4 degrees lower than the dakota digital one at 94 so I am suspicious.

Looking at the colour of my tailpipe, it is definitely running rich.:(

Steve

[clubagreenie]

I'm sorry but ATM I win ANY consumption argument. 38L/100 city and 15 highway. Every sensor changed, on the gas analyser hydrocarbons are off the scale at idle to 1500. From there it gets better to the point at 2500 it's cleaner than a D3 run on the same machine.

Only started since I did the heads, Main concern is the cam is someway involved. Going to try a new ECU first but not holding hope. Just dont want to have to strip it down again.

[Dougal]

Hi

The old fuel consumption thread :o

I have replaced my MAF, O2 sensors and fuel pump but am still getting around 18l / 100k :angry:

Next step is to replace the coolant temp sensor because a failing one of these can cause high fuel consumption and mine is reading 3-4 degrees lower than the dakota digital one at 94 so I am suspicious.

Looking at the colour of my tailpipe, it is definitely running rich.:(

Steve

Get a wide-band O2 gauge set, mount it temporarily and see just how rich it's running.
Once you know sensors are in spec, a re-tune is the best way to sort it.

[TheTree]

Get a wide-band O2 gauge set, mount it temporarily and see just how rich it's running.
Once you know sensors are in spec, a re-tune is the best way to sort it.

Hi

I wonder if the nanocom has this buried in a menu somewhere!

It has long and short term fuel trims and various other things so I will take a look

Steve

[Dougal]

Hi

I wonder if the nanocom has this buried in a menu somewhere!

It has long and short term fuel trims and various other things so I will take a look

Steve

Probably not, the existing O2 sensors will be narrow band for checking whether it's at stoich or not.
The long and short term fuel trims can (I think) only pull the entire fuel map up or down to compensate.
They can't tune for best result across the whole map.

I've just retuned my 3.9 classic. I've been able to make huge improvements right across the board but the fuel map is now a very different shape to the original.
Even if I could have used factory O2 sensors to correct my horrendous rich running (would paint the ground black under the exhaust) it would only have been able to get a good mix at the most common operating conditions.

I haven't yet got through a full tank on the new tune. So fuel consumption is still unknown. But my lean-cruise (16:1) has to be helping, my idle is now stable and it goes like it should on full throttle.

[TheTree]

Hi Dougal

Very interesting and informative:D

This is getting a little beyond my basic knowledge of fuel injection systems, but it seems like this means creating a new fuel map for the beast.

As far as I know only testbook can write new fuel maps to the Bosch ECU and it can only be written 19 times.

Sounds as if my best plan is to replace the suspect temp sender and then take it somewhere like Davis Performance Landys or Graheme Cooper and get a proper tuneup

Steve

[Dougal]

Hi Dougal

Very interesting and informative:D

This is getting a little beyond my basic knowledge of fuel injection systems, but it seems like this means creating a new fuel map for the beast.

As far as I know only testbook can write new fuel maps to the Bosch ECU and it can only be written 19 times.

Sounds as if my best plan is to replace the suspect temp sender and then take it somewhere like Davis Performance Landys or Graheme Cooper and get a proper tuneup

Steve

Happy to help, but yes I only know the 14CUX ECU. Do you know what generation Bosch yours uses? There is an incredible wealth of knowledge on tuning sites like ECU-Connections which is hidden from google searches.

The older the ECU, the more is generally known about them.

I have burnt 10 chips so far tuning my 14CUX. The first 3 or so were trying to make it work.
Then another 2-3 trying to find the right maps. I've only had about 4 serious efforts which were large scale changes and then fine tuning.

So 19 should be heaps.:)

[benji]

Bosch 5.2.1 they are.



Sent from my GT-I9305T using AULRO mobile app

[clubagreenie]

As far as I know only testbook can write new fuel maps to the Bosch ECU and it can only be written 19 times.

Steve

If it's the moronic as in the D2, I think it's even less (12?) writings of major version updates available. These are logged in the ECU and can be seen in the Nanocom. But the tornado chip is done by removing the chip, decoding all the vehicle info, which is why they need your original ECU, and rewriting it, altered to new chips and installing. He's working on a non removable process but has issues.

OBD programming doesn't access all the writable (for tuning) areas of the ECU, so I don't know what parameters are being done at Coopeds and Davis. And despite me having previously worked there, coopers won't tell me what's what.

[TheTree]

Hi

I am not sure of Coopers or Davis are actually re-mapping the ECU but I assume they do if needed.

My fuel consumption figures are still dropping and I have it running better than I ever have on LPG.

So my next step is to replace the suspect temperature sender and see how things go then

Perhaps I will need to dive in to the ECU eventually !

Steve

[TheTree]

Hi

There is an old thread here and it looks like there are not many options for the Bosch ECU

http://www.aulro.com/afvb/p38a-range-rover/134470-p38-after-market-chip.html

Steve

[clubagreenie]

I actual remapping/chipping there is only one option. Coopers and Davis offer something but coopers say it's wholly through the OBD port and Davis, depending on who you talk to, could be OBD or removal of the ECU, BUT, there is also mention of only certain ECU types being able to be remapped and the criteria is EXACTLY as per the TD5 so I'm very wary of that and the fact that I know there's no programming access through the OBD port.

[Hoges]

I actual remapping/chipping there is only one option. Coopers and Davis offer something but coopers say it's wholly through the OBD port and Davis, depending on who you talk to, could be OBD or removal of the ECU, BUT, there is also mention of only certain ECU types being able to be remapped and the criteria is EXACTLY as per the TD5 so I'm very wary of that and the fact that I know there's no programming access through the OBD port.

x2.... "exactly" ;)

Dare I say that the extreme lengths to which the engineers went to in order to complicate what gave rise to an engine map with severe shortcomings, compared to what it could be... makes one wonder what exactly they were trying to achieve...or indeed prevent. As referenced in other posts, the Motronic 5.2 setup was rolled out also in the BMW 3-series of the time and has caused no end of frustration for tuners wanting to improve performance in their European touring cars..

[Pedro_The_Swift]

??...

what word would you use for 5 kilometers to the litre ?

[TheTree]

what word would you use for 5 kilometers to the litre ?

One that invokes the aulro automatic sensor such as **** me :p

Steve