2.5" to 3" turbo outlet downpipe
#1
2.5" to 3" turbo outlet downpipe
I have a turbo that has a 2.5" turine oulet and I want a 3" downpipe. What is the best approach to take:
a) weld 2.5 to 3 inch reducer to turbo exhaust flange and 3" downpipe
http://cgi.ebay.com/ebaymotors/Pipin...ts_Accessories
or
b) V-band 2.5 to 3 adaptor. Looks like alot more money and possibilities for leaks. How are you guys coming off of your turbos into 3" downpipes?
http://cgi.ebay.com/ebaymotors/2-5-4...ts_Accessories
a) weld 2.5 to 3 inch reducer to turbo exhaust flange and 3" downpipe
http://cgi.ebay.com/ebaymotors/Pipin...ts_Accessories
or
b) V-band 2.5 to 3 adaptor. Looks like alot more money and possibilities for leaks. How are you guys coming off of your turbos into 3" downpipes?
http://cgi.ebay.com/ebaymotors/2-5-4...ts_Accessories
#2
Re: 2.5" to 3" turbo outlet downpipe
Either one... Vband is more spendy and gives you some more wiggle room which is well worth it IMO.
I got a spoolin 3" DP that has a 2.5"-3" reducer flipped around and welded to the downpipe/Flange.
I got a spoolin 3" DP that has a 2.5"-3" reducer flipped around and welded to the downpipe/Flange.
#4
Re: 2.5" to 3" turbo outlet downpipe
Is there anything wrong with bolting 3" downpipe w/ flange directly onto the hot side exit (2.5 Dia). I know there will be a 1/4" lip (stepped up) all the way around, but wont obstruct the air flow (but may cause some kind of turbulent effect). thoughts???
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Re: 2.5" to 3" turbo outlet downpipe
I just had my friend weld the 3" pipe right to the 2.5" flange no big deal, I used stainless "cap" bolts (type that use an allen key) because there was no room to get a socket on the flange bolts and it was all good.... make sure whoever welds it doesnt cake it up with filler rod or you will be doing a bit of grinding, we just fused mine with no filler at all.
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Re: 2.5" to 3" turbo outlet downpipe
holy crap dont bolt a 3 inch dp to a 2.5 outlet.
look at garrett's GT style exhaust housings, its a gradual reduction, thats the best way to go.
look at garrett's GT style exhaust housings, its a gradual reduction, thats the best way to go.
#10
Re: 2.5" to 3" turbo outlet downpipe
that will be fine and the best way.
holy crap dont bolt a 3 inch dp to a 2.5 outlet.
look at garrett's GT style exhaust housings
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Re: 2.5" to 3" turbo outlet downpipe
For best flow do not bolt a 3" to a 2.5" outlet. The science behind it is boring but you will not get the best flow. That being said the difference is probably minimal, and unless your racing hardcore then you would probably not ever know the difference.
I would go to a 2.5" and gradually increase it to a 3".
I would go to a 2.5" and gradually increase it to a 3".
#12
Re: 2.5" to 3" turbo outlet downpipe
A 2.5" collector bolted directly to a 3" exhaust WILL interrupt the laminar flow of exhaust up to that point AND if you are hoping to maintain exhaust scavenging for performance, the interruption of this laminar flow by turbulence will diminish, if not negate entirely, the benefits that are achieved by exhaust scavenging. So, yes, bad for flow. It is best to increase diameter slowly over duration. I'm not sure if their is such a product available, but it would be optimal.
#13
Re: 2.5" to 3" turbo outlet downpipe
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