Hi List...
I've been reading your e-mails the last couple of days about header
gaskets. So, I thought I'd share with you some things we've learned in
the last ten years about headers and exhaust manifolds.
We probably see between 100 -200 systems a month-all types, some home
made, some production made, some custom made - from junk to major works
of art. They are from hot rods, custom cars, nascar, drag racers, off
road, road race, formula cars, sprints, atv, snowmobile, airplanes &
lawnmowers. Anything that has a motor I think we've done.
Any type of header gasket is only as good as the two surfaces it seats
against. If the head and port surface does not match the header flange
and pipe opening, no gasket will seal. Thick header flanges are much
better than thin. We feel 3/8" are minimum and 1/2" are better. If
when you bolt the header to the head and they need to be pulled into
place, there is an excess of stress in them and a good chance that you
will have cracking problems down the road somewhere.
If you have them stress relieved, be sure to bolt them to a head while
this is being done. Otherwise, you might not get them back on the
heads.
High heat silicone works great on all headers.
"Anyone's" thermal barrier header coating is better than nothing!! But
remember all coatings are not created equal and all coating companies
are not created equal. Header coating will - in most cases- keep
headers from cracking. Header wrap is the worst thing you can do to
headers. We have seen tour cars and nascar car teams go through 2-3 sets
of headers on one car in a season when wrapping them with header wrap.
Talk to Dave Haller about header wrap..he knows first hand all about it.
If the thermal properties of the coating is good enough, it will also
keep oil from burning if you have an engine "oil down". Again talk to
Dave Haller about this.
There is one coating company that has a thermal barrier that is so good
you can put fiberglass or carbon fiber body parts right against the
headers and they will not burn. Talk to Skip Hedrich about this. There
is much more that I could share with any of you off the list. (remember,
this is not an advertisement--just some things I've learned).
Russ Meeks
PS. Also, about the book that Bob mentioned - "Hot Rods an American
Tradition" - by Peter Vincent..It's absolutely fantastic!! He spent a
lot of time on it and is having a book signing in Moscow, Idaho on
December 8th. We hope to attend. It would make a super Christmas
present for any gear head.
///
/// land-speed@autox.team.net mailing list
/// To unsubscribe send a plain text message to majordomo@autox.team.net
/// with nothing in it but
///
/// unsubscribe land-speed
///
/// or go to http://www.team.net/cgi-bin/majorcool
///
///
|