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Discussion Starter #21
Well I suppose you do get what you pay for and this might explain some things :)

Bought a remflex kit. Pretty neat stuff and I look forward to seeing how long it will last.



But in trying to make a gasket that fit the flange on the header better I figured out what might be the source of my problem. Pictures below :)





 

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Well I suppose you do get what you pay for and this might explain some things :)

Bought a remflex kit. Pretty neat stuff and I look forward to seeing how long it will last.



But in trying to make a gasket that fit the flange on the header better I figured out what might be the source of my problem. Pictures below :)





Just a tip. Make a template with some poster board. I make the outer pattern with the bolt holes. For alignment purposes. Then I took the handle of a screw driver. Pressed it against the edges of the inside tubes. Or I have don most of th same with the gasket material. Just used white out or paint to mark the shape. That way it is as cloose to the shape as possible.

Hope you like th Remflex. I love it.
 

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1st off thanks for using mm like the car was designed (and outside the US uses lol jks ;) )

Im not 100% sure which is what, is that ~5mm difference between the 2 different mid pipes or between the header and one of the mid pipe? Are both the mid pipes the same size and the header is small?

Also are the bolts centered to both or are they off center as well which compounds the problem?

Assuming all the bolts are centered that's ~2.5mm off for each pipe, while not a huge amount it wont be helping with flow between the 2 parts. Depending on the thickness of the flanges you could try and use a die grinder to match them up better being careful not to grind past the weld, but that wont be causing a leak. Try using the digital caliper as a straight edge on the flange and look for any obvious deviations in the surfaces, you should be able to feel it catch on any peaks or see light where there are any troughs.
 

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Discussion Starter #24
1st off thanks for using mm like the car was designed (and outside the US uses lol jks ;) )

Im not 100% sure which is what, is that ~5mm difference between the 2 different mid pipes or between the header and one of the mid pipe? Are both the mid pipes the same size and the header is small?

Also are the bolts centered to both or are they off center as well which compounds the problem?

Assuming all the bolts are centered that's ~2.5mm off for each pipe, while not a huge amount it wont be helping with flow between the 2 parts. Depending on the thickness of the flanges you could try and use a die grinder to match them up better being careful not to grind past the weld, but that wont be causing a leak. Try using the digital caliper as a straight edge on the flange and look for any obvious deviations in the surfaces, you should be able to feel it catch on any peaks or see light where there are any troughs.
Hey sorry, I should have labeled the pictures better and described what I'm seeing. Basically one is the exit flange of the DNA header and the other is the input on the Megan Racing mid-pipe. For now I've given up on using the stock midpipe as the flange there is far too mangled for a gasket to solve the issue.

My real point was just that with such a mismatch in flange sizes I think it's making the area for the edge of the gasket to seal/cover that much thinner. It seems like both the dna flange and megan racing flange are perfectly flat (using a cheap level). I just didn't anticipate there being such a big difference in sizes.
 

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I'd take both the header and the mid pipe to a fabricator. Get the guy to make a new flange on the mid pipe or header, whatever is easiest. He'll have to weld the pipes closer or further apart on one end to compensate for the difference in distances.

Like Peanut said, the flow is going to be crap with that much of a difference.
 
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