Non-stock turbos?
 

I just wanted to see if anyone is using a turbo that is something other than the stock fitment TA0304 Garrett. Perhaps, something more modern, larger, of the VGT type, etc.

Well, the most popular upgrade that has see is the Garrett T3/T4 hybrid, being the T3 Turbine/center section+T4 compressor the easiest (and cheapest) option.

I was thinking a Straight T-3 or a mild trim T3/T4...Is the stock garrett a T-3 exhaust flange?

Jason

I think so.

Yes, the stock manifold has a t3 flange, which makes things very easy for upgrades.

The stock turbo is good for about 25 psi with an intercooler and a low restriction exhaust system. Above that boost, the drive pressure is simply too high, and you will begin to get a loss of power. That actually occurs at ~28psi, so a margin of -3 psi will be proper.

The compressor maps for the stock turbo are wrong as well, if you should ever come across them.

So is it not worth upgrading the stock turbo to another turbo if your running less than 25lbs? I think I would be happy with 15!

Jason

How the hell can the stock .36/.42 be capable of 25psi without superduper heating the air or just plain exploding??

I was thinking 25lbs seemed to be a bit much for that turbo, but I have never tried to push that kind of boost out of one so I wasn't going to say its not possible...

Jason

Easily :). The compressor is capable of more pressure in fact, and as long as you have an intercooler, even the factory one, you will be ok. Of course, an intercooler with greater capacity will be even better in terms of flow and delta T reduction.

Jason, it is not so much the pressure in psi, but more of how much power you are happy with. 25 psi on a the stock turbo is != 25psi on a larger turbo, as you might already know. These engines are extremely strong, and will take the pressure just fine. Provided the HG is not already leaking that is, but that nearly goes without writing for any engine.

If you are happy with the power at 25 psi, then no, you will not need to upgrade.