Exhaust upgrade 300Tdi, I read the posts

[simmo]

I read a lot of posts on different websites, but alro, is the best:D

I'm getting The Madman turbo on in June, it's sitting in the garage waiting to go, Disco transfer case is ready for dispatch from Bushy.

From my net surfing I have come up with the following exhaust options based on the experiences of the forum on various upgrades Td-5 & Tdi.

Almost all Forumians agrees some type of muffler is required and most agree it should be the "tail muffler " or resonator, other wise the car is too noisy. I'm good with that. Most agree going from 2.5 " to 3" on a Tdis of not much value, I'm going with that.

I have come up with following options that suit my need for; not to noisy, and not too expensive, but still give some performance advantages. ( a variation of cheap , fast and good) Standard 300 tdi Landrover pipe is 60mm or 2&3/8"

i) Remove the first muffler and replace with a straight pipe. (lots of good comments about this, cheap, noticeable performance and not too noisy)
ii) Get new 2.5" mandrel bent pipe from turbo outlet to join the exhaust pipe after the first muffler position , ( muffler removed.), connect to the standard "tail pipe and muffler dia 60 mm".
iii) Get new 2.5" mandrel bent pipe from turbo outlet to join the exhaust pipe after the first muffler position , ( muffler removed.) replace all of the remaining pipe with Td-5 2.5" including the tail pipe and muffler.

Does anyone have a 2.5" TD-5 tail muffler they wan to sell?:eek: or a Defender Td-5 exhaust system minus the first muffler, Brisbane area only

What do your think? Thanks for your thoughts cheers Simmo.

[redrovertdi]

2.5 inchs is 63.5mm so you will gain 3.5mm larger pipe, why bother. When i did my research the best was said to be 2.75 inchs but that is not a common size so 3inchs it was and is, the turbo spools much much faster with the larger exhaust, i have one large muffler in the center standard location and thats it, its no noisier than previous set up.
Just my opinion.....

[simmo]

Thanks Redrover, No droning, that's good news the landy is noisy enough as it is. I agree with you about sizing, from 60 mm to 63 mm is only 10% increase in flow area, but my figuring was if its good enough fora Td-5 it's ok for Tdi.

That could be another option, 3" all the way with big muffler in the std position, I din't see that option discussed much on the forums.

What type of muffler did you use a big Lukey, Hi flow?, Magna flow etc? I was worried about he cost of the 3", also the difficulty to make it fit well around the back axle.

thanks for sharing your experience. cheers simmo

[rick130]

You will need a main muffler plus resonator with a 3" system otherwise the noise and done will be unbearable on trips.
There is no difficulty getting the big pipe up and over the rear diff housing and around the chassis, it's harder getting it right when going past the t/case/cross member or the front engine mount without it hitting anywhere under load, but there's plenty of space if done well.

[noogie]

2.5 inchs is 63.5mm so you will gain 3.5mm larger pipe, why bother. When i did my research the best was said to be 2.75 inchs but that is not a common size so 3inchs it was and is, the turbo spools much much faster with the larger exhaust, i have one large muffler in the center standard location and thats it, its no noisier than previous set up.
Just my opinion.....


I went 3" also with a high flow muffler. The turbo spools really well and she goes real sweet.:D

[86mud]

I've got a 2 and a half inch system with no mufflers on my 300tdi 130. It has a nice note but can only hear it when the rear LH window is down. No noise otherwise.

[simmo]

Interesting, I checked the prices of the pipe that replaces the center muffler. In the UK 50 pounds. In aussie $185, more than double the cost. :confused:

It's not like you're buying it from china.

Can buy one and freight it half way round the world for half the price?

How much to get one made locally does anyone have experience ? cheers simmo

[Defendozer]

To give you an idea I got a new 2-3/8" (standard size) rear section of pipe made up complete with a stainless steel resonator for around the $250 - ish mark, give or take a little I can't remember exactly, a centre section would be far cheaper then that as it's more or less just a straight length of piping. I did also get the centre silencer removed for about $60, sounds better with that gone and I found it didn't increase that annoying drone.

The reason I only got the rear section replaced is that the first two sections are 2-3/8" but the standard rear section reduces down to somewhere just above 2", I did notice a difference to performance when I got it done.

Also it needs to be pointed out that there is a big difference in exhaust noise levels between a ute and a wagon, my brothers single cab 130 has a straight through system with no silencers and you can not hear it at all, whereas when my 110 wagon had an un-silenced system there was a near constant drone which might not bother some but I found it quite annoying!!

[simmo]

The reason I only got the rear section replaced is that the first two sections are 2-3/8" but the standard rear section reduces down to somewhere just above 2", I did notice a difference to performance when I got it done.

Dozer, thanks for that info, very interesting about the reduction to about 2" at the end.:eek: That would make a big difference, reducing from 60 mm to 50 mm.
Because I have bad hearing I'm trying to avoid increased cabin noise, so you comments about the rear resonator are helpful.

[mox]

It has been regularly claimed that replacing the front muffler with a piece if straight pipe improves performance. The muffler is basically straight through and the same internal diameter as the 60mm OD pipe. However, the pipe has been pushed into each end before welding, leaving a rough obstruction inside each end about 4mm in diameter smaller. I cut the welds on each end of my muffler, pulled these bits of scrunched up pipe out and rewelded everything using short bits of 2.5 inch pipe to get length the same.. So it is now straight through pipe with muffler. Same crude original fitting up process has been used on standard short rear muffler, which has a smaller pipe (2 inch OD?) out of it. However, after mine got bent by backing into something, I cut the pipe off just in front of the rear muffler and replaced it with a pipe going straight out the back. Had to cut hole in rear chassis outrigger to facilitate this. Presumably allows better gas flow than standard. Slightly bigger and shorter rear pipe with no restrictions inside muffler ends. Maybe small disadvantage is that LH rear lights tend to get dirty from smoke.

[dromader driver]

Cost me about $100 to replace the centre muffler with a hotdog when it finally fatigue cracked. noticeable change in performance on my calibrated test hill.

When removed for a clutch change it was just about fully packed with carbon. If doing it again I would just use a straight piece of pipe the same diameter as the inlet and outlet. Also needs a piece of split 4 inch pipe over the top as a heat shield to keep the floor temp down.

Cheers

[simmo]

Dromader, youre reading my mind mate, :eek:. I wanted to do something about the heat under the floor for 15 years , this might be might my big chance. I was thinking of getting some foil faced rock wool and covering the pipe from the engine bay to behind the passenger footwell. either that or putting a cover on it as you suggest. cheers simmo

[rick130]

Header wrap.
From the dump to the t/case.
Works well.

[edit] There are some pics here http://www.aulro.com/afvb/90-110-130-defender-county/178188-300tdi-exhaust-mods.html and the latest muffler mod from nearly twelve months ago here http://www.aulro.com/afvb/1962140-post1501.html

[simmo]

Rick thanks for the photos a picture is worth a thousand words, that's a very neat job of exhaust pipe wrapping, there isn't much room in there beside the frame and gearboxes etc with the 3" pipe, so foil faced rock wool probably won't fit. I'l probably follow your example and go all the way past the transfer case etc, with the pipe wrapping tape. A hot exhaust close by must contribute to their high operating temperatures I used to use that stuff at work, I believe it's quite expensive. I might try to get some from an industrial supplier, the auto shop prices are steep. I'ts a nice job done on the 3" exhaust connection to the turbo. cheers simmo:)

[rick130]

I turned up a mandrel and flared some 2.5" tube up to 3" to make that dump.

Don't do what I did and re-use the OE flange, get a new one, it just makes life so much easier when welding.
I eventually nickel/bronze brazed it, too many inclusions/too much oxidation from age/use.

I throated the cast dump to 2.5" internally and port matched everything.
I don't believe it really makes a difference on a Tdi, but I just can't help myself.

The original flange/dump had a huge mig bead around the inside of it, it measured somewhere around a 4mm projection inside the pipe which looked like it'd restrict flow badly.
I ground it out and refitted prior to the 3" system and it made eff all difference in performance or EGT's.

[simmo]

Hello Allan,

Price will be $60.00/roll, 3mm x 50mm x 30m roll, plus $15.00 delivery.( in Brisbane)

Total: $75.00 (GST excluded) Regards, Brian Keenan <BKeenan@bellis.com.au>

Guys for your interest, I got this prompt reply from Brian at Bellis insulation products in Coopers plains Brisbane, they're prepared to sell by the one roll, which is good of them. 30 meters would be enough to do your exhaust pipe all the way past the transfer case. 60$ for 30 meters, Its very reasonable compared to the auto shops pricing. This stuff is suitable for service up to 500 degrees C, quite ok for after turbocharger of a diesel normally, short term exposure above that is Ok. Not for petrol V8, you need a higher grade = more expensive. cheers simmo:D

[Defendozer]

I do apologise for hijacking but figured that my question is exhaust related so why start a new thread..

I finished fitting the new VNT turbo last weekend but the exhaust flange on the turbo sits at a slightly different angle which is causing the first section of exhaust pipe to fowl on the transfer case mount, I have since purchased a 152x60mm stainless flexi joint to fit to the down pipe just after the turbo to get around this but I've noticed that there are the "bumps" on the inside that allow it to flex so my question is will that affect gas flow at all? Should I get a lined flex joint or am I stressing over nothing?!!

[simmo]

Relax Dozer, sounds like you've done a nice job, the fexi joint will reduce the stress on your pipe. Yes it will have some esoteric effect on the flow, the corrugations you describe on the inside diameter is about the same dia' as the exhaust pipe it's OK, plus the area of "pressure drop" is very short. Real world the effect is negligible. I'm thinking of doing he same on my car, using a donor Td-5 exhaust pipe. cheers simmo:)

[Jode]

Header wrap.
From the dump to the t/case.
Works well.

[edit] There are some pics here http://www.aulro.com/afvb/90-110-130-defender-county/178188-300tdi-exhaust-mods.html and the latest muffler mod from nearly twelve months ago here http://www.aulro.com/afvb/1962140-post1501.html
I've read somewhere that header wrap must be absolutely tight and without any gaps, as the gaps release high heat that can actually cause the material to burn - at least, a loss adjuster reported that as the cause of an auto fire.

[redrovertdi]

When i had my pipe made i was told not to wrap it as it would crystalise/rust and to make a heat shield instead, any way i ended up wrapping the pipe back to the transfer case probably 18 months ago, when i was under the car a month ago there was rust blistering out from the end of the wrap so i have since removed, but still have the dump pipe wrapped, many here said the pipe wouldnt rust however i must state that my car goes very deep in mud and crap and i think the wrap absorbs alot that doesnt wash out[when i cut the wrap off it was full of crusty mud/dust]

[mox]

Re above comment by redrovertdi about exhaust pipe that had been wrapped rusting, seems to me that this just indicates that the wrapping had caused the pipe to run red hot. This normally causes steel to flake. Note that cast iron is often used instead where high temperatures are expected, eg exhaust manifolds. It has a different problem. ie Being prone to cracking when temperature change is uneven. I am not sure whether stainless steel or other metals sometimes used for exhaust pipes are all prone to high temperature flaking.

[simmo]

Sounds right that wrapping will increase corrosion because sometimes its wet and it holds contaminants dirt etc, close to your exhaust pipe. I'll have to cop that, in the interest of passenger comfort. My car has the original, (un wrapped), exhaust pipe on it and it's still in good shape after 19 years.

The exhaust pipe after the diesel turbo will rarely be in the visible, (red), range during normal operation. That's over 500 deg C 520 I think. The manifold is different because it's upstream of the turbo and can be 150 + deg hotter. The normal glass insulation tape & rockwool can burn, I saw it once at work, an industrial incinerator was out of control, and the top was glowing bright orange heading towards yellow. All the insulation was on fire.

I don' think we going to see those temps on the TDi. I'l go ahead with the wrapping, I have a 30 meter roll and some stainless steel cable ties to hold it on with. But while I'm there I'll look for heat shield opportunities.:)

[rick130]

Just don't wrap the manifold, pretty sure you will crack it if wrapped.

[simmo]

Rick , agree with that, plus it looks like very hard work to wrap it as well.:)