Is there something disadvantageous about this brand new 3" downpipe vs HKS?

VegaSupra

New Member
May 3, 2011
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Poodles;1711361 said:
Correct, it's 2.5" where it attaches to the factory elbow. The elbow is the main choke point in the system.

So just to clarify for all (including myself, of course)... is a "Divorced" downpipe really that much better than a downpipe like the ones Driftmotion makes that fully replace the restrictive elbow, yet don't have the separate divorced pipe for the wastegate?

Seems to me that it goes something like this, from worst to best:

Stock Elbow/DP - ridiculously restrictive.

HKS / Megan Racing style DP - opens up flow significantly, but the 2.5" opening is too restrictive and it still connects to the elbow so not the best choice.

Elbow eliminator DP like Driftmotion's - really opens up much more than HKS since the elbow is replaced and is 3" throughout.

Divorced Elbow Eliminator DP - Maximum flow possible. Completely non-restrictive.

Is this about right?
 
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RazoE

Boobs/Boost, my favorite
Jun 13, 2006
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It's all about turbulence, the better you get the air out the better you can get it in. A divorced downpipe seperates the air streams completely, which would otherwise mix and cause turbulence.
 

gsxr141

Active Member
Oct 24, 2010
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do you guys think the bic ddp is a good one? i would think they have better quality control over the e-bay places.
 

hvyman

Dang Dude! No Way Man.
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Apr 17, 2007
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Yes they have good quality and are hand made and welded. Far better than the ebay shit and he was the one to first start making them.
 

gsxr141

Active Member
Oct 24, 2010
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nice. i was going to get the e-bay one, but i found a new bic ddp local for $300. now i need to get that bad boy on the car.lol
 

1StTurbo

New Member
Jul 23, 2010
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I was looking at the ebay ones also, Glad to have learned something here. What i would like to know is the noise diff between the open DDP and the one that goes back in farther down the pipe.
 

gsxr141

Active Member
Oct 24, 2010
1,158
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it's way louder when under full boost. basically it's like having an exhaust leak any time you're at full boost. honestly, it's no louder when driving around normally. just make sure there's no cops around when you "hit it" lol.
 

northwestsupra

New Member
Sep 19, 2006
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I'm using an eBay one personally. But I am also using a external wastegate. Removed the flange on the dp used the wastegate tube as the new external dump tube. Welded on a v -band for the t-70. At the straight section I'm going to be welding a electric cut off valve then as for the flex section I will use my pre-existing 3" pipe from my exhaust system :) all leaks are solved. Oh btw the wideband location sucks on the eBay dp. They sit right on the firewall

Sent from my Droid using Tapatalk
 

mecevans

Supramania Contributor
Jan 18, 2009
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