Found boost limit on stock bottom and fuel, KA-T

[uuninja]

Originally posted by C-Kwik
Depends on what causes the spike. In this case, it was the signal line coming off. But to build up to 17 psi from 4.5 psi, there is plenty of time to notice a difference.

Yes and no, with a manually actuated waste gate (simple pressure line from the turbo) the waste gate begins to partially open very early. The effect of this is the turbo takes longer to spool. Disconnect the waste gate actuator line the waste gate stays shut and boost builds much faster. The line probably "popped off" under load, which means that boost would surge drastically as soon as the waste gate closed.

[uiuc240]

Originally posted by InferiorWang
What was he doing running 17 psi on a T-25? It's just pushing hot air at that point. There is a reason that the mitsu crowd calls it a T-too small. You really oughtta look into upgrading to a T-28. Flows more air and will give you much cooler air at 17 psi which will lessen the chance of detonation. Sorry to hear about your motor.

And someone above me pointed out the 17psi on a T-25 vs 10 on T3/T4 thing. There is not more are at 10 psi, that is a huge difference there is more oxygen at 17 psi on a t3/t4 at 17 than a T-25 at 17 because of the temperature. PV=nRT
Pressure x Volume = number of moles x R (gas constant) x Temperature. If you want a lengthy description I can give one or dig up a link to one.

First off, I'm NOT running 17 psi on a T25...I was using that as an example. And yes, you're right that a larger turbo is more efficient at higher pressure levels, and therefore pushes less hot air. This is just a more precise and technical way of saying what I was saying. If you take a T25 that squeezes out, what, 350 cfm at 14 psi, and replace it with a T3/T4 that pushes 550 cfm at 14 psi...there's going to be a substantial difference in power. That's all I was trying to say. You're right on with the thermodynamics, bro.

Eric