drag downpipe size???
12-17-2002, 11:15 PM
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drag downpipe size???
sup all!! for all of those who know, what size is the downpipe that comes with the drag 3 kit???? i bought a drag 3 kit for my 2000 si and ive been running with stock piping ever since it was installed. im now ready to get a full piping exhaust. i need to know what size the piping is so i custom my pipes either 2.5 or 3 inch. for example..... if its 2.5 inch can i use 3 inch piping?? any input will help thanks!!!!
12-17-2002, 11:28 PM
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Re: drag downpipe size??? (InfamousRS)
ok for a real answer.
well i cant figure out what you are really asking but..
the basic Drag kit comes with a 2.5 inch piping. they now offer the 3" DP to fit the b series kits but will not clear A/C.
email me or contact us by phone if you are interested in the 3" DP.
the intake/intercooler pipiing is most likely a 2.25 inch diam. your DP 2.5 and it would be a good idea to go with a 2.5 exhaust piping as well.. but if you plan to boost more and not just the basic 6lbs of boost, then upgrading to a 3" wouldnt be too bad.
thanks
Wil
[Modified by exospeedAMcrx, 8:31 AM 12/18/2002]
well i cant figure out what you are really asking but..
the basic Drag kit comes with a 2.5 inch piping. they now offer the 3" DP to fit the b series kits but will not clear A/C.
email me or contact us by phone if you are interested in the 3" DP.
the intake/intercooler pipiing is most likely a 2.25 inch diam. your DP 2.5 and it would be a good idea to go with a 2.5 exhaust piping as well.. but if you plan to boost more and not just the basic 6lbs of boost, then upgrading to a 3" wouldnt be too bad.
thanks
Wil
[Modified by exospeedAMcrx, 8:31 AM 12/18/2002]
for EXOSPEED...!!
12-18-2002, 08:41 AM
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Re: drag downpipe size??? (exospeedAMcrx)
thansk!! so you said its 2.5 inch for downpipe right?? have you ever heard of boost creep if i go with 3 inch??
heres what this guy posted...........
for the exhaust, i would not recommend 3" due to the downpipe being a bottleneck anyways.
maybe using a 2.5" exhaust all the way out, but going to 2.75" near the end somewhere would be useful as an expansion chamber/diffuser to help move the exhaust more efficiently.
also, going too big can cause boost creep issues.
something for you and any other techies to think about...
the shortest distance between two points is a straight line. when exhaust gas spins up a turbine, the gas swirls out the exhaust pipe... since it is spiraling, it's not taking the most direct route and therefore may not expell gases fast enough to be as near to 100% efficient as possible.
a company called Mr. Gas has been producing a diffuser that's been out for a few years now. it's a section of slightly larger bore piping that's been "pinched" a bit, to cause a slight bit of disruption in the exhaust flow... making the spiraling gases take a more direct route out of the exhaust system.
i did that to one of my test pipes when my lude was turbocharged, but unfortunately, i never dyno'd it without the mod to see if it was effective in any way. maybe something for you guys to consider doing unless i get a chance to redo the whole operation.
this guy posted on superhonda.org
what do you guys think?? is he correct?
heres what this guy posted...........
for the exhaust, i would not recommend 3" due to the downpipe being a bottleneck anyways.
maybe using a 2.5" exhaust all the way out, but going to 2.75" near the end somewhere would be useful as an expansion chamber/diffuser to help move the exhaust more efficiently.
also, going too big can cause boost creep issues.
something for you and any other techies to think about...
the shortest distance between two points is a straight line. when exhaust gas spins up a turbine, the gas swirls out the exhaust pipe... since it is spiraling, it's not taking the most direct route and therefore may not expell gases fast enough to be as near to 100% efficient as possible.
a company called Mr. Gas has been producing a diffuser that's been out for a few years now. it's a section of slightly larger bore piping that's been "pinched" a bit, to cause a slight bit of disruption in the exhaust flow... making the spiraling gases take a more direct route out of the exhaust system.
i did that to one of my test pipes when my lude was turbocharged, but unfortunately, i never dyno'd it without the mod to see if it was effective in any way. maybe something for you guys to consider doing unless i get a chance to redo the whole operation.
this guy posted on superhonda.org
what do you guys think?? is he correct?
12-18-2002, 10:36 AM
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Re: drag downpipe size??? (pita106sg)
From what I have seen and heard, the boost crep issue(when adding 3") is due to the DRAG manifold desing...
Theres no real fix for it without getting a different manifold...the MaxRev would be a good budget replacement that would fix the creep problem.
Oh yeah...sorry for the dumass reply I had about the 7" exhaust...
Theres no real fix for it without getting a different manifold...the MaxRev would be a good budget replacement that would fix the creep problem.
Oh yeah...sorry for the dumass reply I had about the 7" exhaust...
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