Tri-power 1/4 mile question
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Drifting
Joined: Feb 2001
Posts: 1,539
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From: new ulm mn
Tri-power 1/4 mile question
Ran my '69 427-400hp for the first time in the quarter mile. Car has original carbs and ignition. Car ran fine and accelerated great until 4500 RPM. AT 4500 RPM it would start to stutter and would not increase in RPM until I up shifted. The secondaries opened up at about 3500 RPM. One run it back fired at about 4500 RPM along with the stutter. Any ideas? Is it the timing or carburetion? Thanks.
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From: Corsicana, Tx
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Could be lots of things. Plugs in good shape etc? I'd disconnect secondary carbs and see if it does same thing. Idea it to reduce fuel pump needs and see if it cleans up only feeding 2bbls. If it doesn't, we're likely back to ignition unless pump is really bad or is pulling air from somewhere.
Any idea on engine condition? A 427/400 has a mild cam...so it doesn't take much valvespring...but if one or more are real weak it could do this.
JIM
Any idea on engine condition? A 427/400 has a mild cam...so it doesn't take much valvespring...but if one or more are real weak it could do this.
JIM
Drifting
Joined: Jun 2007
Posts: 1,404
Likes: 1
From: Ansonia/NYC CT
I had the same problem with my car, though I am not running anything close to the same set up as you, just a stock L-48. It turned out just to be a bad fuel pump. Replaced it, and now she wants to roar right into the red line, if I let her.
