Solution to Bisi header leak?

[wagon-r]

I came across this setup today, which was posted by someone on speedtalk.com as a way to seal slip-on collectors:
http://www.spdexhaust.com/pdfs/Temp_Pages/DSMC.pdf

I have to admit that I'm not sure how it works, but is this a possible solution to the Bisi header leak?

[wagon-r]

Or how about something like Pyro-Putty, which is the first product listed on this web link:
http://www.aremco.com/high-temp-restoration-products/

It's supposed to be "ideal" for repairing pinholes, warps, and cracks in manifolds, headers, and exhaust - good for up to 2000 F.

[illinois_erik]

why not just get them welded, instead of the ghetto fab? it wont be any harder to install vs. a tri-y style header

[wagon-r]

I'd love to get them welded. In fact, I took it in to pure-tuning in Toledo to get it done. But they told me there is no way to weld the inside of the collectors. Just not enough room in the middle of the 4 pipes.

[illinois_erik]

I'd love to get them welded. In fact, I took it in to pure-tuning in Toledo to get it done. But they told me there is no way to weld the inside of the collectors. Just not enough room in the middle of the 4 pipes.

Ok, I just looked up a picture, I see now what youre saying. Seems quite the conundrum. Option A you listed would require using their collector, Option B doesnt seem so bad given the options available

[Tishock]

I'd love to get them welded. In fact, I took it in to pure-tuning in Toledo to get it done. But they told me there is no way to weld the inside of the collectors. Just not enough room in the middle of the 4 pipes.

I was told the same thing when I consulted http://www.afterhoursautomotive.com/


This is what I plan to use when I finish my new catalytic piping.
2300°F Resbond™ 907GF Adhesive & Sealant
http://www.cotronics.com/vo/cotr/rm_adhesive.htm

[wagon-r]

Ok, Option A you listed would require using their collector

Right. I can see this now that you point it out.

[wagon-r]

So, I did some more investigating of the Pyro-Putty that I posted about earlier and the Resbond 907GF that tishock posted.

There are 4 reviews of the Pyro-Putty on Amazon.com. Two of the posters used it to seal manifold leaks - it only lasted about 10 days before it fell off. It sounded like they just put the putty on the outside of the manifold, without any mechanical fixation.

I couldn't find any reviews of the Resbond on Amazon.com, but I did find an interesting thread on an airplane website, discussing sealants for fire walls on airplanes:
http://www.vansairforce.com/communit...p?t-72087.html

If you scroll almost halfway down, you will find a series of posts by DanH, who constructed a fire rig test to test 5 different sealants (the middle 3 are all silicones):
Resbond 907GF
3M FireBarrier 2000
Permatex Ultra Copper
Biotherm 100
Flamemaster CS1900

He constructed a burn rig, calibrated to approx 2000F using copper sheet. The torch nozzle was set up to obtain a tight, horizontal hot spot pattern - and none of the sealant samples were actually in the 2000F hot spot.

Of these products, the Ultra Copper fared the worst - poor hot adhesion and more flammable than the other products.

Resbond was the only material that did not burn, smoke, or outgas (the other 4 products all burned, smoked, and outgassed). "The catch is its hardness; it has little flexibility when cured and none after heating, when it become about like a charcoal briquette. I did a separate test by applying a sample to stainless sheet. After cure I bowed the stainless 20 degrees and the Resbond strip popped off intact; it doesn't bend."

Also, "FireBarrier is easily the best of the silicones. It has excellent cold adhesion and about the same hot adhesion as Resbond. Obviously flexibility and dynamic sealing is good. The char is not as tough as CS1900 char and may blow away in high velocity air, and for the same reason is not as resistant to direct flame exposure. It is highly intumescent, expanding to fill voids as other components burn away."

I'm not sure how relevant this test is for the silicones (although it does suggest that the Ultra Copper is not going to hold up to the heat). But I think there is some good information here on the Resbond. It will certainly hold up to the heat, but it doesn't bend and, thus, may crack due to vibration. Based on the reviews of Pyro-putty on amazon, it appears likely that Pyro-putty will behave similarly.

[Stoner51]

Has anybody tried expanding the pipe with a tailpipe expander.

I did my tri y and it all but stopped the leak. It leaks a little when its cold. I could expand it some more but I'm too lazy.

This is what I used.
http://www.harborfreight.com/small-t...9550-9156.html

steve

[CyborgGT]

I would think it has to be possible to weld in the middle, since the collector itself is still a four-into-one and it's got some pretty decent legs on it before the pipes actually merge. Especially considering you can buy a stand-alone merge collector that looks just like that from fabrication companies.

Maybe if it was customized further to merge the pipes a bit differently:

[illinois_erik]

I would think it has to be possible to weld in the middle, since the collector itself is still a four-into-one and it's got some pretty decent legs on it before the pipes actually merge. Especially considering you can buy a stand-alone merge collector that looks just like that from fabrication companies.

Maybe if it was customized further to merge the pipes a bit differently:

awesome idea, i feel so dur =\

[wagon-r]

Maybe I'm stupid, but I don't get it. The merge collector on the Bisimoto downpipe is fine. The problem is in the 4 pipes coming into the merge collector. They aren't straight at the ends. I also don't see hardly any "legs" on these pipes before they end at the merge collector.

Am I missing something? I'd be delighted to have the pipes merge a bit differently if it could solve the problem, but I don't understand how this could be done.

[illinois_erik]

Maybe I'm stupid, but I don't get it. The merge collector on the Bisimoto downpipe is fine. The problem is in the 4 pipes coming into the merge collector. They aren't straight at the ends. I also don't see hardly any "legs" on these pipes before they end at the merge collector.

Am I missing something? I'd be delighted to have the pipes merge a bit differently if it could solve the problem, but I don't understand how this could be done.

first youd need to hit each pipe with that expander and just get it round again right? the getting the legs in part..umm use a few ratchet straps to pull them all together into shape to fit the merge collector? using that paste or whatever and a block and deadblow and beat it on? maybe even take the female part to a muffler shop to swage the ends a bit. that thing in the above pic would allow you to weld it all together sealed up, a tig would get in there and its probably what was used to make that thing..id get that shit done with the right equipment lmao

[wagon-r]

I can see where you could weld up the primary tubes with the merge bullet in the photo. But what I don't get is that I don't see any way for the collector tubes to go on once the primary tubes are welded up to the merge bullet.

[illinois_erik]

I can see where you could weld up the primary tubes with the merge bullet in the photo. But what I don't get is that I don't see any way for the collector tubes to go on once the primary tubes are welded up to the merge bullet.

Theyd slide in like normal, then youd be using the wings off the bullet to seal everything up where you couldnt get a welding torch into..at least thats how it seems to me.. another option would to get it all together then braze it together with silicon bronze, that would be just as good as a weld, the flame would reach where you need and its a tiny stick of filler rod youd get in, Id think to with brazing capillary action would happen like soldering copper pipes, the melted filler would flow into the voids.

cheapest diy though would to get everything trued up to fit and use that pyro putty upon assembly to glue and seal it together..might not last long with the heat cycles and vibration, i dont think that stuff has much structural integrity after curing. but if youre getting everything to fit nice and snug you might get away with it.