So I guess I should be asking this. How many lb/min can I flow with a single spoolable turbo which I could buy for the $400 range?

 

Upgrade the turbo on your 04.5 and put your 04.5 turbo on your 1st gen. Kill 2 birds with 1 stone.

 

Would that be enough to hold 350-400 hp? I guess it should be because those trucks make 325 stock and you can go to 400 without overheating.

 

Just a compressor upgrade (60mm) will support 350whp. To support 400whp you'll need a different turbo all together. I really dont think a stock 3rd gen turbo will do it. Our 12v head is alot more restrictive than the 24v head so it takes more psi to force the same CFM of air into the cylinder. Higher psi is more heat, and less power potential.

 

Yea thats what I was afraid of.^^

I think for now I will just do the comp. upgrade.

Are there any early trucks that have turbos that can't be upgraded? I have been looking around and on the HTT sight and am not totally clear on this subject yet.

I wouldn't be worried about barking it because I have never barked this 3rd gen once and its a 6spd.

 

If you plan on running bigger injectors, you shouldn't waste your money on the 60mm upgrade. I have talked to many people, and they have all told me when they upgraded their sticks, they had to upgrade their turbo as well.

 

I figure I could probably throw an HX40 on top of the upgrade for a small set of twins if I went with sticks in the future. Would that be worth the aggravation or should I just swap the HX40 single in and trash the stocker?

This will be a budget build, no new $1200 turbos or $300 exhaust manifolds.

 

I wish some place sold a compound kit there you just use your stock turbo and manifold so all you would need is the low pressure turbo, oil lines, and exhaust adapter. Then everyone would have compound kits for around $1600. I think ATS has a kit that uses your stock turbo but you still get the expensive manifold and all the other junk, so its not much cheaper.

 

Either way, kits aren't my thing. I don't want to have to o-ring my head so if I do the twins it will just be a low pressure setup (maybe around 45psi) that would take the strain off of the turbos and just let them cruise in their efficiency range. If I could get a single that would run in the 40-50 psi range for cheap and be designed and efficient @ that psi, I would rather do that. From what I have seen it looks like the HX40 isn't really designed to go that high, but I don't have a map to prove it.

 

If you plan on going with bigger sticks, then do not go with this upgrade, unless you want to keep your eyes glued on the pyro. The majority of the people I have talked to that went with bigger injectors after this upgrade, wished they had saved that money on a bigger turbo. I would look for an S300, but an HX-40 will be a lot cheaper.

 

What about the upgrade w/HX40 or larger but equally cheap turbo on top?
It sounds to me like the upgrade could cool the majority of the pump mods I could throw at it but falls short with sticks.

 

I don't think you will need twins. I know your trying to do a cheap build, but I wouldn't waste my time running a stock charger on a set of twins. Thats just me though. I think the 40 should be fine, although personally, I would rather have an S300.

 

I would rather have the $ in the bank...

 

Ok, I'm sure forum rules don't like linking to other sites, but it's a Mercedes sight so there is no competition. Here are a few Holset Compressor maps including the HX35 and HY35. I was gonna put the Hy35 on my Benz with inj. pump mods due to the tiny 9cm^2 turbine.

http://www.schumanautomotive.com/for...ghlight=holset

 

A third gen turbo will run hotter on a 12 valve than a CR engine at the same power level.
CR engines have injectors that atomize fuel better, a larger intercooler and tubes and have a cylinder head that flows more air.

You can port the cylinder head or change your cam which should lower boost and make more power with cooler egt's.
I am still running my original head gasket with 180,000 miles.