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Old Sep 5, 2007 | 10:25 PM
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whats to really gain hp wise with a stock exhaust....i have a few boltons and a 75 hp nos kit. exhaust is stock. thinking of cutouts and wondering if anyone has done this and will share there experiance.
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Old Sep 6, 2007 | 07:26 AM
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cutout on a stock exhaust...probably 10-15hp

hard to say what the gains would be on the juice.


if you really want to take advantage of the cutout, have a shop put some 3" pipe from the Ypipe back to the cutout...then run the stock 2.75" pipe out to the muffler.

that way when you open the C/O you'll have all advantages of a 3" exhuast
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Old Sep 6, 2007 | 08:21 AM
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I have dual 3" cutouts right at my header collectors.... I LOVE this setup, especially on the 150 shot. you can really tell it opens things up, I can only imagine the gains would be better still with stock exhaust. for the bottle a cutout is the only way to go IMO
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Old Sep 6, 2007 | 01:37 PM
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I gained 10hp with cutouts open versus closed on stock catback, on a 480rwhp GTO.
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Old Sep 6, 2007 | 02:23 PM
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Why do you use the stock catback with a car that has 500+ HP? ^
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Old Sep 6, 2007 | 04:59 PM
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answers i like to here!!!!!
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Old Sep 6, 2007 | 10:15 PM
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I like my Ecutout so I can keep it quiet when I want and LOUD AS ****! when I want.
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Old Sep 7, 2007 | 08:40 AM
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Originally Posted by Fifedogg
Why do you use the stock catback with a car that has 500+ HP? ^
So its only loud when I want it to be?
Because I paid only $250 for the cutouts and catbacks are 600+?
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Old Sep 7, 2007 | 09:01 AM
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I gained 60hp by opening up the cutout verses going through flowmaster exhaust. Sounds ridiculous but the dyno doesn't lie no other changes were made just opening the cutout

Last edited by 00 black ram air; Sep 7, 2007 at 03:28 PM.
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Old Sep 7, 2007 | 09:46 AM
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the flowmater catback is known to loose power vs. the stock catback .
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Old Sep 7, 2007 | 10:31 AM
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Originally Posted by 00 black ram air
I gained 60hp by opening up the cutout verses going through flowmaster exhaust. Some ridiculous but the dyno doesn't lie no other changes were made just opening the cutout

iono i kinda doubt that.... gains are usually between 10-20
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Old Sep 7, 2007 | 03:27 PM
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Originally Posted by transamfreak01
iono i kinda doubt that.... gains are usually between 10-20
Doubt it all you want nothing change it was on the dyno a 1/2 hour worth of time from each run so the dyno doesn't lie. besides that I didn't ask your opinion I was just stating what my experience was with it
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Old Sep 7, 2007 | 03:32 PM
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I love opening the Qtec and scaring the **** out of Harley riders with straightpipes!
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Old Sep 7, 2007 | 04:43 PM
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It's going to depend upon your setup. If you have a big cam and are flowing a ton of air, it'll of course help more than someone with a little cam and not moving as much air. Then there's the oddball cars that respond differently from other cars for no apparent reason.
So just like everything else, there's no set gains.
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Old Sep 7, 2007 | 07:01 PM
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i used them once on a n/a h/c/i car i did, and it slowed the car down. sounds good open, but killed way to much lowend-midrange torque. back pressure(the right amount)is a good thing sometime. but like everything else, depends on the combo.
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Old Sep 8, 2007 | 01:33 PM
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dynoed 391rwhp 362rwtq with stock exaust and 407 rwhp 372 rwtq with my cutout open.
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Old Sep 8, 2007 | 01:36 PM
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Originally Posted by CaliboyTA
dynoed 391rwhp 362rwtq with stock exaust and 407 rwhp 372 rwtq with my cutout open.
typical stock exhaust gain.
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Old Sep 8, 2007 | 01:47 PM
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Never had my old car, a 95 Z28 M6 dynoed, but it was basically stock and I went from 9.0's in the 1/8th to 8.80s on average...about a .15ish drop in ET. For 33 bucks shipped it was worth it.
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Old Sep 9, 2007 | 08:36 AM
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HP = 328 to 340 Torque = 341.6 to 353 with cutout opened back to back runs 5 min. apart. with stock SS exhaust, worth the 30 bucks.
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Old Sep 9, 2007 | 08:55 AM
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I gained 7rwhp and 6 lb/ft through my single cutout on my magnaflow catback.
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