so, wondering why ive kept blowing out header gaskets, tried RTV, nothing would seal. So finally got to digging around, and noticed that its the bottom of the header gasket every time. Some tard drilled my flanges wrong, and the flange hangs about 1/4" lower than the head, so its leaking out there.



example, black is head, red is the header



maybe take it to a shop and just get a bead ran in the bottom? to seal it?
cut off the flange and get a new one welded on? this would be a PITA though since i would have to add a little piping, and get everything to measure exact to fit the crossover again.

 

Have a reputable welding shop weld a bead onto it and plane it smooth. Shouldnt be a problem for a decent metal working person. Have them make it 3/16 thick like the rest of the flange for strength. Thats what I would do. FWIW, I dont use big dollar gaskets on my camaro. I use stock manifold gaskets from felpro for a 1992 chevy tbi pickup with a 350. They are the perforated metal, if they loosten up and leak, tighten them up and they seal, no more blown gaskets. Eric L

 

i am just using felpro 1406's, arent too costly, like $15 up town.

 

It sounds like welding the bottom of the header port could increase your sealing surface. But is there mis-match at the top??

 

Well if that drawing is at all accurate, the headers are too small for the exhaust ports anyway.

 

When I first did mine I made the mistake of copying SBC flanges. BUT they are about .150-.250 different. I bolted mine up and they were too low. I just took a 10mm cutter at work a slotted the flanges. I just pulled my hot side off after I ride (so i can paint it tonight) and they seemed to seal great!

I also am gonna start running percey header gaskets.

Jay

 

so i need to slot it, and pull the headers up towards the top?

 

I had that problem with a set of square port flanges - and would never seal.
My solution was the right flange, but you probably don't want to do that now... so I dunno. Would probably take a good bit of work to fill and recut those.

 

in order to do a new flange, i would have to redo the whole header, and the crossover. Not something I want to do at this point

 

percys dead soft leaked. The earls sealed up nice and you can replace the inserts

http://store.summitracing.com/partde...5&autoview=sku

 

well guys, i figured it out. somewhere along the line, something warped in the header/crossover area, so the header was not laying flat, left a gap. took the header off and stuff, measured it, checked it to a spare head, and the gasket, it was fine, its just somewhere where the crossover and the header meet that its off.

 

another thing that you may want to consider is not using the gaskets at all and just running a thin bead of red rtv...thats all i ever do with turbo headers, i have yet to meet a set of gaskets that dont blow out over time...even seen a couple sets of copper gaskets fail.

 

The percy's aluminum gaskets are absolute junk. I had a set blow after literally 5 miles of cruising. I switched to solid copper and been running the same gasket for years, plus its reusable. Some run no gasket at all, but both surfaces MUST be very true.

 

anytime i have used RTV, it blows out....

i apply a 1/8" bead, let it skin for 15 minutes, put it on. blows out every time. This is using copper RTV.

 

Weird, I thought you sold your Turbo Setup?