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**'68OrangeSunshine** · 06-15-2007, 07:00 AM

I have a set of Clifford headers on my 292, so I don't remember that problem. I've been running the headers since 1978.
If you are having excess vibrations, you might check on the health of your harmonic balancer. A wobbly damper can throw a lot of things out of kilter, especially on these L6s. Over-revving (going over the redline at [only] 5000 RPM) can foul up the HB.
Before I had a shop weld up a set of dual exhausts -- back in my college days -- I had a pair of steel packs pushed into the header collectors and held up in back by bailing wire. Sometimes when crossing rural rail tracks, things would come loose. The headers would get loose and performance woud begin to suck.

06-15-2007, 07:00 AM	#2
'68OrangeSunshine Senior Member Join Date: Feb 2002 Location: Tucson, AZ USA Posts: 7,622	Re: inline 6 exhaust flange ("donut") frequently failing I have a set of Clifford headers on my 292, so I don't remember that problem. I've been running the headers since 1978. If you are having excess vibrations, you might check on the health of your harmonic balancer. A wobbly damper can throw a lot of things out of kilter, especially on these L6s. Over-revving (going over the redline at [only] 5000 RPM) can foul up the HB. Before I had a shop weld up a set of dual exhausts -- back in my college days -- I had a pair of steel packs pushed into the header collectors and held up in back by bailing wire. Sometimes when crossing rural rail tracks, things would come loose. The headers would get loose and performance woud begin to suck. __________________ Every 25 years I like to rebuild that 292, whether it needs it or not. Last edited by '68OrangeSunshine; 06-15-2007 at 07:04 AM.