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  Topic Review (Newest First)
04-14-2019 11:05 AM
Piggity 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.
04-13-2019 05:17 AM
humbucker87
Quote:
Originally Posted by Pnut00 View Post
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.
04-13-2019 12:45 AM
Pnut00 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.
04-12-2019 08:00 PM
01 SolarYellow
Quote:
Originally Posted by humbucker87 View Post
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.
04-12-2019 06:31 PM
humbucker87 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





04-12-2019 04:46 PM
TobiasSing
Quote:
Originally Posted by black86 View Post
when did you order your last set? really missing my mazzuri v2 but I've heard dezod is a headache to deal with [emoji848]

Sent from my Pixel 3 XL using Tapatalk
It was around October 2017. I'd just get Figs
04-11-2019 07:09 PM
black86
Quote:
Originally Posted by TobiasSing View Post
on my second Dezod greens now
when did you order your last set? really missing my mazzuri v2 but I've heard dezod is a headache to deal with [emoji848]

Sent from my Pixel 3 XL using Tapatalk
04-11-2019 04:59 PM
01 SolarYellow
Quote:
Originally Posted by Bezik777 View Post
Iím having gasket sets made as we speak ... pm if you need a set.
Who are you having do it and in what material?
04-11-2019 04:06 PM
Bezik777 I’m having gasket sets made as we speak ... pm if you need a set.
04-11-2019 02:41 PM
mesooohoppy
Quote:
Originally Posted by humbucker87 View Post
I know that for my stock midpipe I can look at it and tell the surface isn't true anymore....it didn't even seal from the get go showing how poor the two surfaces mate.



1. Is there anywhere we can buy just that aftermarket shaped gasket? I see a DNA kit on ebay for $19 but it includes the manifold gaskets and bolts too.....All I need is the double flange gasket.
why have you not made the mating surfaces smooth? you should be doing that to take any additional variables out. if it didnt even seal, obviously its bad enough it needs to be fixed.

have you tried emailing the seller on ebay?

also, you can try and order a dezod header, but according to others, he will take your money and you will not get anything. also i wouldnt even bother with the green headers. the cats clog up so fast, i dont know why anyone would buy them in the first place.
04-11-2019 02:38 PM
TobiasSing
Quote:
Originally Posted by black86 View Post
which header?
on my second Dezod greens now

Quote:
Originally Posted by humbucker87 View Post
Dude the struggle is real. I am both a car nut and a personal finance FIRE (financially independent retire early) prescriber. The two things couldn't be further from each other. The most depressing thing is the spreadsheet of spending on this car so far....could be worse for sure, but there have been some mistakes This last set of RE71r's lasted two weekends and are now done.

My monthly car budget to savings ratio is about 1:10 so maybe it's time to spend a bit more for once. I'm going to see if one of these DIY gaskets can hold with the megan midpipe.
I hear ya. If you saw my spreadsheet, you'd probably have an aneurysm lol. But I've definitely learned that it's just worth it, literally, to do it right the first time. Spend the big bucks now, or later with the extra you wasted on cheap stuff. Besides, what good is money if you never spend it? lol.
04-11-2019 05:49 AM
humbucker87 Thanks guys for the suggestions. Mathieu that would be interesting to take a look at the tundra gaskets.

@Pnut00 I think it has been blowing out in the same spot so I should take a closer look at the flange and make sure there isn't something weird there. To be honest the more I look at my stock midpipe there is no way it will ever seal against a flat flange like the aftermarket one. Because of the age and rust it's not even close to flat.

Another interesting observation I made last night (although not surprising given the price of the DNA header) is that the exhaust gasket that blew out did not align with the exit of the header very well at all. Below I drew a red circle approximately where the header pipe would line up with the bolts are through the holes. Meaning that the bottom of the gasket would be getting non stop hot exhaust gas passing over it. As suggested earlier I'm going to try and cut my own gasket from remflex material and make sure it lines up much better.

04-11-2019 03:53 AM
Mathieu Bernier I've got OEM gasket on my header. Those you buy at Toyota shaped like a donut. Since th header is a bit bigger than oem manifold I've bought some Toyota Tundra exhaust gaskets. I can tell you the part number later. Still got the bag at work
04-10-2019 08:59 PM
Pnut00 do they always blow in the same spot? With both the mid pipes?

If so then you can pretty much say that is the weak area on the headers not the mid pipe. Can it be machined flat again? Or can the shop cut it off and weld on a new flange of better quality and flatness?

If the flanges are flat there is no reason it wont seal for these the same as it will for a stock header, if both are using the same flange.
04-10-2019 08:41 PM
humbucker87 A lot of mine are 4, 25 minute sessions each day. So I'd guess I got 7 or 8 hours out of them. They are fast though for 200TW.
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