Thread: Am I going to kill my 460?

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I have a 71 Lincoln with a rebuilt 460 in it that has been making some clatter noise when going up hills, or putting my foot into it. The car seems to run great at highway speed. The block is a donor from 1972, bored 60 0ver, with the original 71 heads I had with the car. The carb is a brand new Edelbrock 600cfm, and I put a Pertronix II electronic ignition on the car. The heads were ported while we did the rebuild, and we added a set of full roller-rockers, and Keith Black pistons. I have no faith in the goofus who rebuilt the motor because of some other car-related issues, so now I have brought it to a different guy who seems to know his stuff.

Today he adjusted the new carb for me, and then did a compression test on one of the cylinders. He said that it came out at 175 psi. He said that the reason why the car was clattering under load was probably pre-detonation because the compression ratio is so high. When the original guy built my car, he had a cam ground to his specs, but because of the issues I had with him, he never gave me a cam card so we are flying blind. The new guy said that he would not be surprised if my compression ration wasn't 10:2.

He said that there is a good chance of damaging the motor because of the pre-detonation problem. He recommends yanking the motor very soon, pulling the heads ofrf and seeing exactly what we have to work with, and staring over with a good foundation to work from. Does any of this sound out of line to the more learned folks here on the board?

(edited to add that the car has a new tranny, dual exhaust, and a Weiand Stealth intake manifold. He considers the intake manifold to a component of the problem, and recommends a different one when we pull the motor.)

Michael