New Exhaust = More boost?

[91dsmtalon]

I have a stock 91 awd talon, I've spent the last few months saving up money to get it in good running condition and to prepare everything to start modin' it. I have an autometer boost gauge and running only free mods it pushes about 11 psi, recently i installed a 3" turbo back system, and noticed boost running up to 13-14 psi, my question is this common? The previous owner bought the car after it had been gutted and rebuilt the motor/tranny and the turbo. Ive noticed the turbo sounds suspicously loud compared to my friends 1g FWD, I also hit full spool at like 3-3.5k? so first question is could the exhaust raise my boost levels, and second is it normal for the stock turbo to spool so quick? Forgive me if it sounds newbish

 

[turbo90gsx]

Yes and yes. These are both GOOD symptoms of an open exhaust system. For one, there is much less backpressure, allowing exhaust gases to flow in and out of the turbo faster, which means your spool up time will drop. This also means that will be an increase in an overall boost pressure because the gases are flowing at a higher rate, spinning the exhaust wheel faster. This is very common, and happened to me when I had just installed my 3" exhaust on my old 14b.

 

[91dsmtalon]

Sweet I was kinda wishing I might have had an upgraded turbo and didn't know it

 

[DSMcamaro]

boost creep. same things for me with a 2 1/2" downpipe and 2 1/2" exhaust.

http://www.dsmtuners.com/forums/showthread.php?t=185503

 

[I-luv-em-all]

boost creep. same things for me with a 2 1/2" downpipe and 2 1/2" exhaust.

http://www.dsmtuners.com/forums/showthread.php?t=185503

That is possible.

But he was just saying that it went from 11 to 13-14, he didn't say the boost never stops.

Free flowing exhaust will always increase boost a little, if you were running on the stock level before. I was running 16-17psi before I got my RnR 3" o2elim turboback, and after the install it stayed the same. Every car is a little different too.

 

[alex99gst]

I just run 10 for now (waiting on fuel mods) but the other day I unbolted it right before the cat and zit tied it down so for about 15 mins I had a very deep mean sounding exhaust with 12psi. Zip ties ignite and sound stops, back to 10 psi

 

[91dsmtalon]

, no I am not having boost creep, whew.