Open downpipe = Overboost?

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05-15-2008, 08:49 AM

#21

wes65

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Quote:

Originally Posted by compy

Look out, Cobras can get over 50HP from a K&N intake. Now thats poor design.

Yeah, thats what i hear. Something about emissions or insurance or something, so they restricted the intake for lower HP that was easy to get back.

05-15-2008, 08:53 AM

#22

wes65

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Quote:

Originally Posted by mike_671

I hear you on the stock exhaust. I do the same. DD with it on and race with it off.

So, I'm pretty broke, but this is what I'm thinking. Get 3" from the DP back to the axle. Adapt my stock axleback to bolt up the 3" with a flange. Just pull the axleback off and swap in a turndown when im going to race. Then later on when the cash makes itself available, i can dump the axleback and go with a decent 3" muffler.

06-06-2008, 02:21 AM

#23

marek

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Quote:

Originally Posted by wes65

so I pulled my test pipe out. Well, my wastegate was set around 10 psi and i had an MBC set up for around 12 psi.

Seems to me that once you pulled the test pipe your exhaust became MUCH less restrictive, and had you readjusted it, it probably would have held at the right level.

I just got done putting a 3" enthuza no-cat system on and it definately spools much faster. I am using a EBC, so since it is adjusting boost on actual pressure, it can actually compensate for the change in flow (mostly anyway).

or not