Exhaust question????
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Digga
Joined: Sep 2003
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Exhaust question????
This has been an anoiying topic for me because everyone seems to have different opinions.
Integra's exhaust piping? how big is too big... I've been told by some that for an all motor 2.5 custom pipe is too big (back pressure issues)... others say 2.5 is the way too go?? what is right? I don't think anyone would want to spend money to lose horsepower... so you can understand my dilema.. Custom or cat back??
lets here what you got to say.. if you know what u are talking about.. for the rest of you save your 2 cents and put them in a jar until you can afford a car
Integra's exhaust piping? how big is too big... I've been told by some that for an all motor 2.5 custom pipe is too big (back pressure issues)... others say 2.5 is the way too go?? what is right? I don't think anyone would want to spend money to lose horsepower... so you can understand my dilema.. Custom or cat back??
lets here what you got to say.. if you know what u are talking about.. for the rest of you save your 2 cents and put them in a jar until you can afford a car
Chavez Motorsports
Joined: Aug 2003
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Well, what compression will you be running? If high compression and built with possiblity of spray.....go with a 2.5, if you dont plan of going to crazy with it get a 2.25, or get a 2.5 with an exhaust the has a silencer so you can controll the BP......
Just my .20 cents.......I have a car
Just my .20 cents.......I have a car
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Chavez Motorsports
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TR Balla Donor Supreme
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If you're buying a mass produced, mandrel bent exhaust (Thermal, Apex'i, etc) get 2.25, if you're getting a custom exhaust (muffler shop) get 2.5.
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it is a common misconception that exhaust needs some back pressure. the problem with using an exhaust that has too large a diameter is that it slows exhaust gas velocity. part of the header's purpose is to balance exhaust gas flow and actually use one cylinder after another to create a vacuum effect, pulling the gas out as the piston pushes it out. if you wanted back pressure then you could just stick something in the way and keep the large diameter piping, it would crap out the whole deal.
2.25 is fine for your avg exhaust, but i would also recommend a mandrel bent cat back setup, i loved my hks super dragger, it was 2.25 with a cannister muffler, and had a small resonator in the mid pipe (after cat, pre axle).
the 2.5 is also fine, but if you don't need high end breathing then you would just lose power on the bottom end due to the larger diameter on the collector, and if running it into a 2.25 exhaust its just a waste. stay away from this size for an LS
if you are budget minded than you could always just pick up a glass pack, magnaflow makes and excellent 2.5 diameter, in 18 and 24 inch lengths. get a mandrel 45 or 90 to make a turn down. for some reason the magnaflows flow better than a straight pipe.
2.25 is fine for your avg exhaust, but i would also recommend a mandrel bent cat back setup, i loved my hks super dragger, it was 2.25 with a cannister muffler, and had a small resonator in the mid pipe (after cat, pre axle).
the 2.5 is also fine, but if you don't need high end breathing then you would just lose power on the bottom end due to the larger diameter on the collector, and if running it into a 2.25 exhaust its just a waste. stay away from this size for an LS
if you are budget minded than you could always just pick up a glass pack, magnaflow makes and excellent 2.5 diameter, in 18 and 24 inch lengths. get a mandrel 45 or 90 to make a turn down. for some reason the magnaflows flow better than a straight pipe.
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Originally posted by RONIN
it is a common misconception that exhaust needs some back pressure. the problem with using an exhaust that has too large a diameter is that it slows exhaust gas velocity. part of the header's purpose is to balance exhaust gas flow and actually use one cylinder after another to create a vacuum effect, pulling the gas out as the piston pushes it out. if you wanted back pressure then you could just stick something in the way and keep the large diameter piping, it would crap out the whole deal.
2.25 is fine for your avg exhaust, but i would also recommend a mandrel bent cat back setup, i loved my hks super dragger, it was 2.25 with a cannister muffler, and had a small resonator in the mid pipe (after cat, pre axle).
the 2.5 is also fine, but if you don't need high end breathing then you would just lose power on the bottom end due to the larger diameter on the collector, and if running it into a 2.25 exhaust its just a waste. stay away from this size for an LS
if you are budget minded than you could always just pick up a glass pack, magnaflow makes and excellent 2.5 diameter, in 18 and 24 inch lengths. get a mandrel 45 or 90 to make a turn down. for some reason the magnaflows flow better than a straight pipe.
it is a common misconception that exhaust needs some back pressure. the problem with using an exhaust that has too large a diameter is that it slows exhaust gas velocity. part of the header's purpose is to balance exhaust gas flow and actually use one cylinder after another to create a vacuum effect, pulling the gas out as the piston pushes it out. if you wanted back pressure then you could just stick something in the way and keep the large diameter piping, it would crap out the whole deal.
2.25 is fine for your avg exhaust, but i would also recommend a mandrel bent cat back setup, i loved my hks super dragger, it was 2.25 with a cannister muffler, and had a small resonator in the mid pipe (after cat, pre axle).
the 2.5 is also fine, but if you don't need high end breathing then you would just lose power on the bottom end due to the larger diameter on the collector, and if running it into a 2.25 exhaust its just a waste. stay away from this size for an LS
if you are budget minded than you could always just pick up a glass pack, magnaflow makes and excellent 2.5 diameter, in 18 and 24 inch lengths. get a mandrel 45 or 90 to make a turn down. for some reason the magnaflows flow better than a straight pipe.
Basically, if you're looking for a little more prep in the lower rpm range and you're making around 150-160 whp (hypotheically speaking) then 2.25" would suit your needs. I was making around 180whp in my Crx and really liked the 2.5" exhaust. If possible, try to get a mandrel bent system, that way there isn't varying diameters that the exhuast gas flow through.
Its a secret
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i got a 2.5 custom catback. i like it kinda loud and its alot different than stock i can as stated before u can notice a different in bottom end but mid to top is golden
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