i'm going to be changing my exaust setup soon.

first, my current setup consists of: pacesetter lt's, pacesetter ory, stock catback, 3" in/out aerochamber, stock tailpipe turndown after axle.

at the track i run open exaust out the y-pipe. i don't loose any lowend but gain roughly 3/10's in the 1/4 compared to running full exaust.

here's what i'm thinking of doing. getting rid of the pacesetter y and i'm torn between these two setups....

first choice
second choice

the magnaflow y is on it's way and don't want to go true duals. i plan on staying N/A also. i just want to know if i would see better gains at the track with 1 or 2 cutouts. thanks guys... lance

 

I think you should use 1 3.5" cutout. In fact I know where one is you can get cheap

 

Two 3" cutouts right after the collectorwill net oyu the best flow thats how I did mine and I can feel a SOTP gain over the corsa.

 

nice drawing

 

I'd think the 3'' ORY into the 3'' cut-out will be plenty for what you're
doing. I think evidence is shown by your dyno. With the cat-back off,
you hit about 5500rpm and that **** flatlines. If it had more in it, power
wouldn't flatline out past 6500rpm. It'd more than likely drop off... Then,
you put dual cut-outs and it would flatline again. Didn't happen however.
I could be completely wrong tho

Let me know what you decide to do.

 

thanks for the replies guys, keep em comming.
yall like that drawing hun, haha...
white thanks for the offer man, i already have a 3" sitting next to me.
kyle send me a pm, i think you confused me, lol...

 

IMO you want your motor to breathe up top you need to get as much air moving out of there as possible and cutouts right off the collector is the best/most efficient way. You dont need the tq down low that increased back pressure will give you and you are going to go to a different style intake in the future so you would already have the exhaust to support your new setup. v8 is running duals and having good luck with it.

 

What I'm getting at is exhaust flow is not the problem.
I say this because you made peak HP at 5500rpm and
then held a flat power curve out past 6500rpm.
I believe it held to 6700rpm where Tony finally let out of it.

If there was a restriction in the exhaust, power would fall off
after peak. It does not one bit... It holds for over 1000rpm after
its peak.
If this was the scenario... dual cut-outs would again flatten the
hp curve... can't do this... already super flat.


The problem is increasing 'peak' numbers and to do that you
need to bring in more charge. HMM, problem there. The intake.
Look what it did to your power curve. Stopped climbing at
5500rpm.

See if that is more clear.

 

i got this kinda setup. i can actually feel a loss of bottom end with it open when compared to closed going through the dynamax bullet and corsa which are both straight though.

 

well lance with that one cut out it would be like taking your pipe loose at the collector, so all in all you would be the same, I'm running dual cutouts right after the long tubes, just like your second drawing, but i have dual pipes into muffler and dual out. good luck either way you go.