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Helix DP + Borla Hush - the solution

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Old Sep 15, 2004 | 11:44 AM
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Helix DP + Borla Hush - the solution

Since this topic seems to come up every couple of weeks, I wanted to post some fixes for this. Here's what I did.

Went to Midas and got a 3" double donut gasket (part# EN1493). They normally charge a few bucks for it but the guy there gave it to me for free. The gasket fits nicely between the flat helix flange and the socket on the borla system.




A good idea would be to take a dremel to the helix flange and bevel the inside a little for the gasket to seat better. I didn't do this 'cause I had already had my dp ceramic coated and didn't want to mess w/ it.
Old Sep 15, 2004 | 07:05 PM
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im sorry but im not familiar with the problem you are describing and fixing, could u explain? do they not fit well together?
Old Sep 15, 2004 | 08:24 PM
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Originally Posted by SkylineR35GTRx
im sorry but im not familiar with the problem you are describing and fixing, could u explain? do they not fit well together?
The helix down pipe is a 3" in diameter tube. Now while the borla hush is also 3" its connector was disigned to use the stock 2.5" donut gasket. I suppose he's doubling the gaskets unless the 3" donut actually mates up to the 2.5" flange, I dunno though.

My solution was instead of tapering the helix to 2.5" was to weld a 3" sleeve fitting to the helix downpipe so i could clamp the borla hush to the helix downpipe.
Old Sep 15, 2004 | 08:38 PM
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Originally Posted by RoadSpike
The helix down pipe is a 3" in diameter tube. Now while the borla hush is also 3" its connector was disigned to use the stock 2.5" donut gasket. I suppose he's doubling the gaskets unless the 3" donut actually mates up to the 2.5" flange, I dunno though.
No doubling of the gaskets. The hush mates up perfectly to the 3" donut
Old Sep 15, 2004 | 09:25 PM
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so what was the problem ur fixing..i dont see it, im sory.
Old Sep 15, 2004 | 09:27 PM
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Originally Posted by SkylineR35GTRx
so what was the problem ur fixing..i dont see it, im sory.
simply the flange on a borla hush is 2.5" and the helix is 3" since there is a size mismatch you need parts to make them compatible.
Old Sep 15, 2004 | 09:38 PM
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I went to performace exhaust in milpitas and bought a 3" flange welded to a 5" long piece of straight 3" diameter pipe.this is the "new adapter" you need to mate to the helix.
Then, loosen the v clamp on the borla and hammer/pull/urge the stock borla "adapter" out.
Replace with your new adapter and tighten the bolts. Leak free and pretty easy.
Old Sep 15, 2004 | 11:51 PM
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Originally Posted by RoadSpike
simply the flange on a borla hush is 2.5" and the helix is 3" since there is a size mismatch you need parts to make them compatible.
In addition to the size mismatch, the borla flange is not flat and designed to match the stock donut gasket. Many have had custom welded adapters to replace a short piece of the borla system w/ 3" pipe and a 3" flange. This would be the best solution but cost a lot more than just using this Midas gasket.
Old Sep 16, 2004 | 12:06 AM
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you should contact mpj performance in haywayd ca, he has a hush fix that is basically a true 3 inch flange almost a half inch thick welded onto a 3x6 inch piece of stainless tubing that slides right into the hush cat back system
Old Sep 16, 2004 | 12:52 AM
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Originally Posted by Long_Travel_WRX
you should contact mpj performance in haywayd ca, he has a hush fix that is basically a true 3 inch flange almost a half inch thick welded onto a 3x6 inch piece of stainless tubing that slides right into the hush cat back system
Like I said above, this is the best solution. But unless its free then the gasket from Midas works great.

edit: another thing to consider is that the stock system uses a donut gasket to allow movement in that joint. By using a flat flange adapter to a flat flange downpipe you've essentially locked it solid. the midas gasket works just like the stock setup and allows some "flex" in the connection between the downpipe and catback exhaust.

Last edited by Mister 2; Sep 16, 2004 at 12:59 AM.
Old Sep 16, 2004 | 12:58 AM
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does this problem only occur with the hush? because i'm about ready to buy a cat back and already have a Helix dp
Old Sep 16, 2004 | 03:04 AM
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Originally Posted by debbid
does this problem only occur with the hush? because i'm about ready to buy a cat back and already have a Helix dp
no, a few others are stock fitted so they would be 2.5" donut flanges.

You can search for what will fit since this has been asked many times before. Also check out the reviews section of this site, lots of good info and opinions there.
Old Sep 16, 2004 | 04:36 PM
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i wonder what the shops do to fix this problem..
Old Sep 17, 2004 | 01:54 AM
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they cut the end of the pipe where the donut slides into and weld the slip flange solid to the piping and slide a flat collector style gasket in there, then like a month or two down the road it starts to leak cause the slip flange that came on the catback is really thin so it starts to warp and then your gasket fails, like i said contact soren at mpj hes got the fix and its all bolt on
Old Sep 27, 2004 | 07:47 PM
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Also if you want that extra horsepower and dont mind your borla to have more of a loud rumble to it, get 17 inches of stainless steel and have an exhaust shop cut out the resonator and replace it with straight pipe. Cheers

Rush



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