Hybrid Turbo for Discovery 2

[Steve223]

Hi,

decided to go with Bruce Davis Hybrid Turbo for the D2 to remove the bottom end lag and give it a bit more grunt. Like to compare to the variable vein I have in Defender and we will a before and after Dyno run.

cheers

Steve

[Mundy]

I have debated with BD the pros and cons of differing turbos and when we last discussed it he advocated a bigger, fixed vane turbo with a larger bore which he said would address the low end lag. I purchased a Bell Autos variable vane turbo.

In theory, bigger turbos give you more grunt once spooled up but suffer from lag due to their increased mass. If you increase the vane angle to give better boost at low revs you get overboost at high revs. Smaller turbos spool up more quickly but don't give you the boost at higher revs. If the BD turbo is still a fixed vane turbo, I don't see how he can give you better low end and high end performance.

BD installed my VVT but didn't realise he had to bypass the ecu boost control and tried to fiddle with the turbo vane angle (which is bench tested and set by Bell Autos).

My VVT has completely transformed the performance of my vehicle at low revs. I have a manual and now never stall on a hill and the kick in at 1700RPM now doesn't happen. I can pull away in 4th on the flat at 1200RPM and in 5th at 1400. BTW, the VVT comes with a boost box to fool the ECU into thinking there's no over boost. I was more than happy with the high end performance (I have a BD reprogrammed ECU).

It may well give you what you want. But I'd do some thorough research before you commit.

[Steve223]

I have debated with BD the pros and cons of differing turbos and when we last discussed it he advocated a bigger, fixed vane turbo with a larger bore which he said would address the low end lag. I purchased a Bell Autos variable vane turbo.



In theory, bigger turbos give you more grunt once spooled up but suffer from lag due to their increased mass. If you increase the vane angle to give better boost at low revs you get overboost at high revs. Smaller turbos spool up more quickly but don't give you the boost at higher revs. If the BD turbo is still a fixed vane turbo, I don't see how he can give you better low end and high end performance.



BD installed my VVT but didn't realise he had to bypass the ecu boost control and tried to fiddle with the turbo vane angle (which is bench tested and set by Bell Autos).



My VVT has completely transformed the performance of my vehicle at low revs. I have a manual and now never stall on a hill and the kick in at 1700RPM now doesn't happen. I can pull away in 4th on the flat at 1200RPM and in 5th at 1400. BTW, the VVT comes with a boost box to fool the ECU into thinking there's no over boost. I was more than happy with the high end performance (I have a BD reprogrammed ECU).



It may well give you what you want. But I'd do some thorough research before you commit.


I have the VVT in the Defender and love it Bruce thinks he can do better with HB so give that a go and report back how it goes.

[Mundy]

I, too, will very interested how it performs. Please let us know how it goes. Is it a fixed vane?

[twr7cx]

Isn't this old news? I thought you were doing this months ago?


we will a before and after Dyno run.

I don't think they dyno readings are going to be worth much in the debate. It's likely the hybrid will pull bigger numbers, but the dyno won't show which what it's like for on road (and off) driving when your at low RPM's pulling away etc - this is when I would expect the VNT to have an advantage, it might not boost as high and have the same peak power, but no lag means instant kick.

[Steve223]

yes old news however I did not get around to it due to all the other mods so now it's happening. Dyno is cancelled as apparently heavy duty torque converter makes it not worth it so we will do some time trials with auto logic instead today. No VV but hybrid turbo.

I'm going to be playing in the Watagans tomorrow so will see how it goes.

Bruce will first work on giving low down torque until I'm happy after that he will put overall performance up

[Steve223]

Hybrid Garret Turbo with modified Internals - solid aluminium billet with a 10% larger intake wheel and 8% larger exhaust wheel90886

[ramblingboy42]

Emma Chisset?

[ramblingboy42]

How long do the OEM turbos last?

I'm around 300k's and from what I'm reading I'm expecting a number of different things to expire soon.

[robbotd5]

How long do the OEM turbos last?

I'm around 300k's and from what I'm reading I'm expecting a number of different things to expire soon.

MMMM.......i'm thinking the same mate. Trying to come up with an excuse to feed to SWMBO to upgrade to a VNT. I've already told her it will make starting off with the van in tow much easier.....can anyone confirm that the turbo lag is greatly reduced and the upgrade is worth the outlay?:):D;)
Regards
Robbo

[twr7cx]

can anyone confirm that the turbo lag is greatly reduced and the upgrade is worth the outlay?:):D;)

Turbo lag is not greatly reduced, it is eliminated. My D2a has 10psi on take off straight off idle and 17psi by 1,500rpm.

[Steve223]

So far not to impressed we will try a couple of different maps, Bruce thinks my HDS torque converter may be the issue however does not make sense really .

Otherwise hybrid will go and replaced with VVT

[Jazzman]

What is a good VVT worth for a D2a TD5 anyway? Can it just be bolted straight in?

[Steve223]

What is a good VVT worth for a D2a TD5 anyway? Can it just be bolted straight in?


yes straight replacement but you will need a remap to see a difference

[Mundy]

Steve223, as I said before, I will be very interested if the BD turbo works as you'd like it (is my cynicism showing through) for the technical reasons given and because of my doubts about BD's expertise with them. I am happy to be proven wrong however.

My Bell Autos VVT just bolted straight on and didn't require a remap, but I'd already had a BD remap which may be relevant.

With my manual, the turbo lag was all but eliminated. With an auto, as indicated by twr4cx, I'd expect no lag at all.

[Mundy]

What is a good VVT worth for a D2a TD5 anyway? Can it just be bolted straight in?

In April 2013, my Bell Autos VVT and boost box cost GBP845 plus GBP130 for Shipping and insurance from UK. Yes, mine just bolted straight on.

[Steve223]

Steve223, as I said before, I will be very interested if the BD turbo works as you'd like it (is my cynicism showing through) for the technical reasons given and because of my doubts about BD's expertise with them. I am happy to be proven wrong however.



My Bell Autos VVT just bolted straight on and didn't require a remap, but I'd already had a BD remap which may be relevant.
.


I'm as curios as you as I share your opinion but would be happy to be proven wrong by BD.

I tried my VVT on Defended with BD non VVT a map no better result, default TD5 map no results, Bell map yea baby flying

[Steve223]

hm BD thinks the problem is my HD torque converter however according to Dave Ashcroft this should rather improve it then hinder.

does anyone run 34" a HD torque converter and a VVT a with success on a automatic ???

[Tombie]

33s, HD TC and not a worry in the world :)

[Jazzman]

In April 2013, my Bell Autos VVT and boost box cost GBP845 plus GBP130 for Shipping and insurance from UK. Yes, mine just bolted straight on.

About $2200 seems like a reasonable price for a new turbo, but having said that I've got no idea how much a standard turbo is. I assume it is not that much different.

I plan on getting a remap from TD5 Inside shortly anyway, so if i do get a new turbo it should be sweet.

[twr7cx]

yes straight replacement but you will need a remap to see a difference

I beg to differ here. You'll get an improvement even on a stock standard setup. A remap to suit and larger intercooler will further increase your benefits.


hm BD thinks the problem is my HD torque converter however according to Dave Ashcroft this should rather improve it then hinder.

does anyone run 34" a HD torque converter and a VVT a with success on a automatic ???

I run the Ashcroft HD converter and a VNT and no issues on 33" tyres with 4.11 gearing. When Justin Cooper last drove my vehicle after he redid the exhaust manifold studs for me, he commented that it would give the V8's a run...


About $2200 seems like a reasonable price for a new turbo

It gets a lot cheaper when the AUD picks up in value. Remember you might have to budget an additional 15% for import duties and GST - sometimes you get away with it and sometimes now.


I plan on getting a remap from TD5 Inside shortly anyway, so if i do get a new turbo it should be sweet.

There's some differences in the remap for a standard turbo and VNT. TD5Inside might be willing to adjust it to suit if you upgrade the turbo later though.

[Steve223]

I beg to differ here. You'll get an improvement even on a stock standard setup. A remap to suit and larger intercooler will further increase your benefits.



hm not for me there was no noticeable improvement. As I had to get BD to restore it to default as he encrypts his maps I drove it with 3 different maps and only Bell did the job. also have 3" exhaust with cat, and larger intercooler

[td5inside]

An hybrid VNT its the way to go :) LOL

Hybrid from stock and VNT are very different things... VNT its always a better option but its usually alot more expensive. We have been working on an Hybrid exactly because we can have a bolt on solution about half the price of the VNT. Results are good for the price even using the more expensive mfs compressor billet.

Regarding the VNT, the only thing i believe its very good in the Turbotechnics turbo its the fact its a bolt on unit. Other specifications are a bit old, lets say, in the turbo technology world.

What we do overhere its to convert turbos from other cars. We need to make some small changes to exaust and a flange to the manifold and pipes but it works. We make them work with pressure (instead of original vacuum) fitted them with forge actuators wich can be tuned and adjusted for pressure, vnt opening, etc etc The 2056 from the 5 cilinder Alfaromeu its excellent, aswell as turbos from VW LT etc, etc.

I also have a lot of faith in the new 1756VK from the 2.7 audi wich has amazing torque from lower revs.

Remap to stock, hybrid and VNT are completly diferent...

Regards,

[Mundy]

About $2200 seems like a reasonable price for a new turbo, .....

Luckily for me, in April 2013, it was GBP0.69 to the AUD, so only cost me about
$1400. Not sure I could justify the cost now despite the magic improvement.

[twr7cx]

Luckily for me, in April 2013, it was GBP0.69 to the AUD, so only cost me about
$1400. Not sure I could justify the cost now despite the magic improvement.

I paid similar to you as I purchased when the AUD was parity with USD so it was well placed against the GBP too. I think I would still probably do it at the current cost though - the D2 is a much nicer car with it.

[Jazzman]

Sorry for hijacking the thread. But thanks for the responses.