Power diff. w/ cut out open vs. closed
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From: Southeast of Disorder
Power diff. w/ cut out open vs. closed Well I finally hit the dyno last night and was kinda stunned at the difference in power with my QTP electric cut out open.
The exhaust consist of this: Pacesetter LT's, 2.5" off each collector, going into a 3" merge leading to a 3" intermediate pipe with a Spin Tech 3" mandrel bend over the axle split in 2.5" tailpipes. I picked up 27 h.p with the cut out open. It doesn't honestly feel that different, but the dyno says other wise.
If I switched to 3" pipes off each header do you all think it would make that big of a difference or just let it ride like it is?
The exhaust consist of this: Pacesetter LT's, 2.5" off each collector, going into a 3" merge leading to a 3" intermediate pipe with a Spin Tech 3" mandrel bend over the axle split in 2.5" tailpipes. I picked up 27 h.p with the cut out open. It doesn't honestly feel that different, but the dyno says other wise.
If I switched to 3" pipes off each header do you all think it would make that big of a difference or just let it ride like it is?
That is a restrictive exhaust. For comparison, when I had a cutout on my Hooker setup (Hooker LT, ORY and catback) I only picked up 4rwhp and 7rwtq with the cutout open. Suffice to say I have since removed my cutout. 
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TECH Resident
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From: Southeast of Disorder
built 347, LS2 Heads, custom cam.
I really think its in the Y pipe itself. I've had Spin Techs on several different cars and always noticed a power increase with them over different brand mufflers.
I really think its in the Y pipe itself. I've had Spin Techs on several different cars and always noticed a power increase with them over different brand mufflers.
spintech mufflers suck. i had the crossflow just like you and lost about 4mpg and it fell on its face like stock at about 80mph. and i have just bolt ons. i will never use another one again. i never got mine dynoed but i could feel the difference. granted it sounded good. but thats it. i couldve done better with a stock muffler.
Well I finally hit the dyno last night and was kinda stunned at the difference in power with my QTP electric cut out open.
The exhaust consist of this: Pacesetter LT's, 2.5" off each collector, going into a 3" merge leading to a 3" intermediate pipe with a Spin Tech 3" mandrel bend over the axle split in 2.5" tailpipes. I picked up 27 h.p with the cut out open. It doesn't honestly feel that different, but the dyno says other wise.
If I switched to 3" pipes off each header do you all think it would make that big of a difference or just let it ride like it is?
The exhaust consist of this: Pacesetter LT's, 2.5" off each collector, going into a 3" merge leading to a 3" intermediate pipe with a Spin Tech 3" mandrel bend over the axle split in 2.5" tailpipes. I picked up 27 h.p with the cut out open. It doesn't honestly feel that different, but the dyno says other wise.
If I switched to 3" pipes off each header do you all think it would make that big of a difference or just let it ride like it is?
I picked up 24 rwhp on the dyno last night too man. I have a feeling that I'm going back to true duals. My exhaust setup is ARH longtubes into an ARH Y with dual cutouts into a 3'' intermediate pipe into an SLP dual dual catback. My car is a 408 though, so I'd say that setup is a little restrictive.
