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Old 04-14-2012, 03:07 PM   #1
bigreddog
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Question Boost drop with cat?

I had 17 psi with my catless side pipe and with nothing but the cat and over the axle 3" I lost 2 psi?
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Old 04-14-2012, 03:14 PM   #2
Meistwagon
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same thing happened to me. stock pipes the whole way back i only made 6 or 7 psi then i ran open downpipe and made and it went up to 11. when i put on my third setup (side dump) it was around 9 so i just returned the boost actuator adjustment nut and turned it up to 13. boooost! my guess is the less back pressure after the turbo the faster it can spin
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Old 04-14-2012, 04:25 PM   #3
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Back pressure is bad . . . . mmmmkay


Higher flowing cat might help a little, otherwise 100% normal.
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Old 04-14-2012, 07:39 PM   #4
ard
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Yeah, I lost a lot of top end when I went from 3" catless/mufflerless side exit to 2 mufflers and over the axle.
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Old 04-14-2012, 07:47 PM   #5
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ya chocked it up dude. let er breath... or in this case, exhale. Think of it as a fat kid with asthma that just ran 60 feet. haha Might not be the best example, but im sure you got it.
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Old 04-14-2012, 11:14 PM   #6
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Old 04-15-2012, 09:20 AM   #7
bigreddog
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The cat is a high flow 3" spun cat. Very nice for tight places and flows enough air for a 5.9l engine.

Soo back in goes the mbc!
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