Holsets and Duramax

[Ncostello]

Anybody have any ideas on where I should start to install a Holset turbo on my 02 Duramax HD2500? I think the mounting and such can be done as there are various vendors selling pedestals to mount Garretts etc. But I want a Holset. And the Duramax crowd doesn't seem to know tons about Holsets because they just aren't around them much.



Mainly... I want to pick the right one. HX40 some say is too small. Some have said the HX50 is better. But I don't know how to size the exhaust housing etc to do better than the stock IHI turbo.



For what its worth... the IHI is a decent turbo from what I've read. But its nearly silent most of the time. Especially at lower RPM's. I want to make some more noise and get a little better performance out of a stock setup.



I won't do electronic enhancements on this truck either. FWIW.

 

[Forrest Nearing]

I don't think you're going to get better performance out of a stock setup by going backwards technologicly and using an old, out-dated noise maker...



put EFI live on it, and enjoy

 

[Ncostello]

I'm not really looking for huge power gains. In fact not really looking for more power at all. If I do a turbo, exhaust, air intake and some new stock injectors at some point... and I get more power... thats OK. But I'm good with the stock LB7 code power at 138,000 miles now.



I just really can't stand the IHI and how silent it is. There is virtually no turbo sound even with a straight exhaust. Sounds silly I know... but its my toy and I want it to be fun too .



The 02 I have is really not as high-tech as the 05's and up. Its a non EGR non Catalyst engine. Kinda like a 2002 ISB 5. 9. Except common rail. Maybe more like the 03 ISBe 5. 9. So a HX really wouldn't be that out of place compared to the IHI... which was replaced by the VVT Garrett in 05 on the LLY code engines.



Some folks have tried to redesign the IHI with different wheels etc... but they all give up. Its as good as it is stock. Which isn't bad. It just sounds bad.

 

[Forrest Nearing]

ahh, so it doesn't have a variable nozzle setup?

 

[Ncostello]

No variable geometry turbo. 01-04's had an IHI wastegate turbo. This is the 1st gen Duramax. The engine RPO Code (three digit GM codes for specific options... ie: Z28) is LB7. This Duramax was built from 2001-2004. 5 and is generally considered to get the best mpg's and has the highest potential for added power (in general). Its factory non-EGR and no catalytic converter... except for some 03-04 models sold in California.



Its pretty basic and isn't any more complicated than say a 2003 Cummins Common Rail. Its kinda like a 7. 3L Powerstroke... but Common Rail Technology for injection using a CP3 Bosch Pump.



In 2004. 5... the LLY code was introduced with VVT turbo and slightly different heads. Then in 2005. 5 the LBZ code was introduced with a couple more minor differences. Now the DPF trucks run the LMM code engine which is basically a LBZ with DPF and some minor changes. The biggest change came with the 2nd Gen LLY in terms of turbo and injectors being located external to the cylinder head valve cover. The remainder have been changes to allow increased horse power... pistons, rods etc all tweaked for 10HP here and 20 HP there over the years. All of the above here were VVT Garrett turbos I believe except my LB7 earlier model.

 

[Forrest Nearing]

yeah, I hear ya... I'm just not that well versed on them



do you know the specs on the IHI? inducer, major, exducer, etc. ?

 

[Tinman]

I have a Garrett BB turbo on my 06 and it will whistle real good. Sounds great.

 

[GDMRTN]

I have a friend who will put a super 40 wheel on your stock turbo. Then it'll wake the bottom end up a lil and sound good too!! We tried this on an 02 and the guy is wild about it. Sez much better low end power and nice sound. Otherwise stock motor. This may not work for you but it did for us.

 

[Ncostello]

I can easily get the specs. I've seen them a few times but don't have them handy.



GDMRTN... is this a diesel shop? I'm not familiar with a Super40 wheel.

 

[GDMRTN]

It's the wheel put in a high flow hx40. Better known as a super 40. It's a friend of mine that does it. Just a one guy shop. Playin around and found this lil trick.

 

[Ncostello]

Let me know how to contact him. Or see if he can do this on mine. Just curious.

 

[JJPage]

First let me say, I know zero about Duramax's.



My older brother just purchased a used 07 GMC. It has a Holset turbo and I am pretty sure it is stock, is this a vvt? Something your not able to control?



Do the 07 GMC's have regen? I know I'm not helping you, just curious.

 

[Ncostello]

If its the old body style 07... its has no DPF and regen. The new style ones all do. I guess it depends if the HD's were available in 07 as the new body style. Some 07's were called Silverado Classics. They were the old body non dpf.



The new duramax engines are nearly identical to the previous non-dpf models... with the exception of the dpf system. The turbos from 05 to current were VVT... Garrett. Even the newest ones.