Do open cutouts affect A/F ratio?
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Do open cutouts affect A/F ratio?
So I have dual cutouts welded behind my headers on my y pipe. I was just wondering, will they affect A/F ratio when open? I spray the car and don't want to run into any problems.
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Ok, would it cause the wideband to read a little off??? I may have been running a bit lean but my A/F was around 12.3 during the whole run and didn't know if the open cutouts affected it or not.
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We have seen a difference on the dyno depending on the location.
EX 1 : F-body with a single cutout in I=pipe before axle..no change
EX 2 : any car we have seen which has them near or directly off the headers did change the A/F a 1/2 point or more leaner
EX 1 : F-body with a single cutout in I=pipe before axle..no change
EX 2 : any car we have seen which has them near or directly off the headers did change the A/F a 1/2 point or more leaner
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Hmm....I am actually thinking about ditching my Hookers for a set of LPP's this spring, if I do I might go ahead and get a single cutout in the I pipe with and electric valve. Basically because then I will be spraying a 200 shot on the stock bottom end and I'm too lazy to get under the car and uncap them LOL
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Hmm....I am actually thinking about ditching my Hookers for a set of LPP's this spring, if I do I might go ahead and get a single cutout in the I pipe with and electric valve. Basically because then I will be spraying a 200 shot on the stock bottom end and I'm too lazy to get under the car and uncap them LOL
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i planned on doing the QTP electric cutout but the only way it would mount flush aginst the manual cutout was with the electric motor pointing straight at the ground, which would only give about .5" of clearance, so needless to say that didn't work, I ended up just leaving it as a manual cutout (which i have no problems opening and closing at the track, even with a lowered car) and i saved the $200 for go fast parts, instead of convience parts
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True. I had two Summit brand electric cutouts. They were actually good looking quality and worked very well, but when I mounted them on the cutouts they too were about 1/2" off the ground. I just sent them back to summit and got my money back. I think it was only 250 for two cutouts and the wiring kit.
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yea for the electric cutout it would have either had to be welded up with the cutout facing in to the middle of the car instead of out to the door, or the tube would have to be cut and re-welded for the specific combo i had to mount it with out the motor pointing at the ground, i just said screw it and sent the part pack to summit and used the $$ elsewhere
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Reversion does affect WBO2 readings with a cutout. The closer to the engine the cutout is the worse the reversion.
WBO2 readings aside, a cutout will usually lean out the burn in the chamber.
How much depends on how much backpressure you have before opening the cutout. If you are running near the lean limit corked up, then yes it might cause you a problem.
In the "old days" guys had to jet up the carb & pump shot for running open exhaust.
WBO2 readings aside, a cutout will usually lean out the burn in the chamber.
How much depends on how much backpressure you have before opening the cutout. If you are running near the lean limit corked up, then yes it might cause you a problem.
In the "old days" guys had to jet up the carb & pump shot for running open exhaust.