B16, B18, B20
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By poorman type-r
#208737 Oh ok well i will take what both of you have said and build my motor through that. Now for exhaust should i get 2.25" or a 2.5"?
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By poorman type-r
#208738 Oh ok well i will take what both of you have said and build my motor through that. Now for exhaust should i get 2.25" or a 2.5"?
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By Greasedmonkey
#208777 at least a 2.5"
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By poorman type-r
#208783 O ok because some guy was telling me 2.25" for torque and 2.5" for horsepower.
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By Greasedmonkey
#208835 hp comes from torque.

hp = (torque * RPM) / 5250
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By poorman type-r
#208852 Yeah that makes sense. Well he was talking about back pressure.
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By That One Dude
#208873 The difference in back pressure between 2.25 and 2.5 is minimal. You're adding an inch in diameter to your stock tubing. Back pressure is no longer a topic of discussion.

I'm running 2.5" from the header collector back. Good times are had since ditching the stock exhaust. :D
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By poorman type-r
#208878 Haha nice. Well why do company make a full exhaust when all it is is piping. There isn't a differnce between a 200 dollar exhaust system and a 1100 dollar Mugen exhaust is there?
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By Greasedmonkey
#208900 R and D in the Cat backs.

The bolt on systems are usually 60mm. with is 2.36 inches. you will get some power, but a custom mandrel system for you car for your motor will make more, but it will cost more to get. a generic muffler shop fabbing up one wont make as much power.
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By poorman type-r
#208911 Oh ok. Im not trying to jump off topic but how do you know all of this? Lol
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By Greasedmonkey
#208945 years of learning. Ive been doing this for 12+ years.
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By Greasedmonkey
#208963 Not really. I was for a bit, but Im not anymore. I like messing with cars to be my hobby, not job.
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By poorman type-r
#208969 Well i know who to talk to if i have any questions haha :thumb:
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By 93hatcheg
#209101 My question is why does the bolt on make more power than a exhaust fab shop? If the bolt on kit is 60mm why would that make more power than the 60mm piping the muffledr shop welded for me. Its the same thing. I mean stainless steel piping can't increase hp noticibly over regular exhaust steel, that would be like saying that my falken 195/50r15 tires make my car faster than kuhmo 195/50r15 tires