Is 15psi ...15psi?

[dboosted1]

I have heard that a te44 (which I have) @ 15psi produces the same power as a stock turbo @ 15psi, but the TE44 just does it easier. Is this true? I have been told that the 44 really dosnt start waking up til about 18psi? thanks

 

[UNGN]

I have witnessed this personally with a TA49 vs. stock turbo. At 18 psi, the TA49 ran identical ET and almost identical mph to a stock turbo at 18 psi. Up until that moment I had been convinced by others that a larger turbo allows you to run less boost and make more power. Turns out that is a myth, especially when you are comparing a larger turbo to a stock turbo in its "sweet spot" of 17-18 psi. Only when I started turning up the boost did the curves diverge. 22-23 psi is the "sweet spot" for a TE44.

Porting the heads or using a cam lowers the "crossover point" where a larger turbo makes measurably more power at a given boost level than a smaller turbo.

 

[dboosted1]

So when i cruise areound in my TR with the 44 @ 15psi I might as well be driving with a stock turbo? Thanks for the fast response UNGN. I know when I check my post and I see that little red, white and blue AMX? launching i have a good response coming.

 

[SMOKIN86T]

funny you mention the small turbo vs big turbo thing....
some guys i know are doing a shoot out of small turbo and ported heads vs big turbo

should be intresting

 

[strikeeagle]

As you know, the air flow requirements of a typical TR engine can be provided by any of several turbos, some smaller, some larger. For a given operating point, all would be operating at the same air flow and pressure (i.e. boost), and consequently making the same power.

Take a bone stock motor, for example. At 15 PSI a stock turbo and a 76 (assuming it wouldn't surge itself to death) would provide the same flow and make the same power, the 76 albeit very inefficiently.

The distinction is that when more air needs to be moved, such as at high boost or for a highly modified motor, the stock turbo will not longer be able to support the requirement.

But believe me, for the situation I described, there is absolutely no difference.