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Author Topic:   1 flattop 7 domes
posted January 30, 2004 07:34 AM
Can anyone tell what combo to use to mix and match this set? Would like to run a flattop in the #1 and domes in the rest.

posted January 30, 2004 07:59 AM
I assume you are wanting to do that to pass inpection? What if they pick a different hole to check some night?
I wouldnt do it, it seems like it would be hard on the whole engine combo to me if you have 7 cylinders making equal power then one that drops off... wouldnt be real smooth i would think.

Ego Racing
posted January 30, 2004 09:47 AM
NASCAR driver used to do this quite often. They would have an engine at 400 cubic inches but if you pumped the front cylinders it was a 358. The thing is you have to match weight and pressure in each set of pistons per crank journal. That means you have to have two flat tops one in #1 cylinder and one across from it. Have it balanced per set of pistons and rods. You MUST build the complete motor as if it was a high comp motor. You will not have an easy time setting the carb up either as the front two cylinders will be using fuel and timing different. To get the most out of the setup you will need a cam custom ground for the two low comp cylinders, slightly less lift or ratio to help correct the fuel charge.
This is only a hypothesis based on experience and what I have read. Hope it helps you out.

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