Slip-on vs flange-style header/sidepipe connections?

[Mike Braddock]

We're to the point of building a set of sidepipes for our EM and are curious to hear the pros and cons of each of these style header/sidepipe connections. I've heard that the slip-on connections are difficult to seal and still be able to remove down the road. I've also heard people say the rectangular bolt together flanges like to blow the gaskets out and leak. Can you tell me what style you have and what your experience has been with them? Thanks.

Since we're going to build our own headers anyway, we're also considering building a set that are one piece from the header flange to the end of the 4 into 1 collector, welding on a 3-1/2" flange and bolting the 'mufflers' onto that flange. This seems like the best way to ensure a seal, but I've only seen a handful of cars done this way. Oddly, an original CSX was one of them. Was this an option on the early cars? What do you guys think about this method? I think Don Gibson also had this style headers on his FFR two years ago at R&G; here's a picture showing his car with turnout bolted directly to the collectors:

http://www.kitcarillustrated.com/ima...unandgun26.jpg

Thanks again!

Mike

[Clois Harlan]

Mike,

I think George Anderson has the same type set-up on his FE. I know they sure were loud. I don't think George does many (if any) things that don't work well. I consider George a Master.

[Tony Ripepi]

Hello Mike,

Unique and Superformance use a flange mount on their header to sidepipe connection.

Go To : http://www.uniquecobrareplicas.com/ and look at their fabrication shop and you will see a set of their headers. The SPF site does not really show their headers but check it out the next time you see one of their cars.

I have a Unique with a 427 in it and a SPF with a 460 . I like the flange connection vs what I have seen on other cars with a slip fit. The flange seals better and prevents the exhaust leak that gives you a backfire on deceleration. Seeing the grade 8 bolts all around the flange and the ability to put a cooper sealing material between the surfaces makes sure you have a good seal.

Besr Regards,

Tony R.

[Don]

Mike

Look at the following site for some more options. There was at one time a self sealing clamp arrangement that allowed for the muffler to be removed. You may want to contact Burns as I did not see Clamps listed as a separate page on their web site

www.burnsstainless.com


Don

[Wade Chamberlain]

My setup has 4-bolt flanges. If the mating surfaces are flat, skip the gasket all-together and use a little Ultra Copper RTV (high temp stuff). 12,000 miles in 9 months, they've never been apart, and no leaks!

[Jack Zupan]

My setup is flange to flange also. I just used Permatex UltraCopper high temp RTV silicone gasket maker without a gasket and got an excellent seal. I had put them together last spring and they did well all year with no leaks. I'm pretty sure I first got the idea from Double Venom in a CC thread a while back

Jack Z.

[scratch]

Mike,
I have slip fit (well almost "fit") and I like the simplicity but I can advise that the headers must be in-line with your sidepipe collector or you will have leaks and backfire.

I mean dead on alignment.

If you remember to do this, you CAN get a great look and seal without too much afterthought and sealer.

Depends on your patience level I guess, mine isn't that great but I wanted to go the original method and like the "racing" look.

my 2 cents...


scratch

[moorepower]

We have seen alot of both kind of headers in the shop, and I have to say a slip fit with sealer is the only way I would recomend, unless the flanges are 3/8" thick or thicker. Any flange thinner thatn this will bend eventually when tightning. If you do use them, don't overtorque and do use blue locktight on the threads. The blue will handle the heat and you will be able to get them loose when you need to. moorepower