I have Langdon's H/W's on my 292. Actually, I have a Tri-power set up and they flow approx 250 CFM's. That's straight from Tom Langdon. I installed them in 2000 and have not adjusted, or touched them since. I get 18-20 MPG's too.

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1940 ChoppedChevyCoupe

Loud Pipes Saves Lives!