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Discussion Starter · #1 · (Edited)
Why 11 psi?

This is , I'm sure, a basic turbo question.
If our wastegate opens "stock" at 7.3psi (or similar, pls don't reply,"it's actually 7.41256666psi @ sea level"); why does a free flowing exhaust and intake raise the PSI of the wastegates actuation? I know it spools faster, but why does the wastegate not open at 7.3psi as it does with std exhaust & intake?
I have no MBC, 2.5" crush bent exhaust & K&N panel & I'm always up @ 11psi. I can't formulate a reason for higher PSI. The Wastegate takes it's boost reading straight from the compressor, so 7 psi is 7psi, right? Can someone that actually knows why this happens help me out?
 

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FlySwat said:
A free flowing exhaust causes the miniscule stock waste gate to be outflowed.
See I see this alot but I have the same mods as "crusty' and my boost is still at the stock mark??:confused: But there may be a difference mine is cat back exhaust(2.5") Do you have turbo back upgrade 'Crusty'? Or is my waste gate just performing admirably(for now)??
 

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Discussion Starter · #4 · (Edited)
1FIERCEGT said:
See I see this alot but I have the same mods as "crusty' and my boost is still at the stock mark??:confused: But there may be a difference mine is cat back exhaust(2.5") Do you have turbo back upgrade 'Crusty'? Or is my waste gate just performing admirably(for now)??
No, cat back only with a straight through muffler.
BTW, My name is Jim, Crusty is a nickname I've had for years from watching "Crusty Demonds of Dirt" videos, before going either moto-x-ing or mountain biking, for "inspiration" to do stooopid stuff. SETH IS GOD!

Flyswat: thanx man. I was PM'ed by Woo. He said the WG spring was set at 11 PSI but the stock exhaust delivered 4 PSI of back pressure. 11-4=WG opens @ 7psi.... remove the back pressure & the WG opens at 11psi. Sounds like the same thing, kinda, just explained differently I think????
 

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OKay but I'll assume you still want to be called Crusty in the public foroum right? And Woo's explanation doesn't explan why mine did not change and it sems we have the same exact set up(mods that is)?
 

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Discussion Starter · #6 ·
Crusty or Jim, it bothers me not.:)

What type of muffler do you have? straight thru or restrictive? I can look straigt thru mine ( b4 it was fitted obviously), it looks like any other muffler from the outside except both inlet and outlet line up with no restriction/bends/offset pipes. With the exhaust only my boost increased to 9-10, the K&N seemed to push it to 11psi.

edit: I have no resonator on the exhaust. Just my cat & 1x Muffler.
 

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I have a straight through muffler as well, and Open Air k&n filter and a stock cat, but no resonator. My pipes are 2.5" so??
 
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