Thread: Good Combo?

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Not my original words, but an excerpt from an article in Corvette Fever magazine that underscores Techinspector's concerns:

"An important concept to understand is that combustion is not an explosion. Ideally, it is a flame wave, initiated by the spark, which burns across the combustion chamber. This smooth burning generates the rapid rise in cylinder pressure during the power stroke.

Knock is the negative result when combustion occurs somewhere else in the cylinder, in addition to the plug. Like the spark-plug-initiated flame wave, the second wave expands so a collision between the wave fronts occurs. This collision produces a radical spike in cylinder pressure. Instead of a firm, even push down on the piston, the pressure spike hammers it down. This is strong enough that it can ultimately burn a piston, crack a piston ring or ring land, or a spark-plug electrode. These excessive pressure spikes can damage even engine bearings. When you hear a metallic rattle while driving, that is the sound of detonation and, in most cases, the cure is fuel with the correct octane.

One mechanical aspect that affects compression is the piston top. A dish increases cylinder volume, which reduces compression. In contrast, a domed piston decreases volume and increases compression. If detonation occurs, the piston top, ring land, or rings can be physically damaged due to the excessive pressure shocks created by colliding flame waves."

You may want to reconsider the domed pistons in favor of flat tops.

to get to 10.5 is like falling off a log with a 454 you have bore and stroke on your side a 340 dome will get you 10.2 working down the heads and deck will get you close i have used big domes 14.8 cr to flate tops that up to you

I have decided to go with the Erson 238/246 @050 621/621 lc 108 that Pat suggested. I have a friend that is going to give me a set of headrs that will fit the frame wells of my truck. I am sure they are not the best for my application but they were given to me. They were bolted to a motor but never started. They are ceramic coated "Rewarder" brand block huggers. When I measure them they have 1-3/4" primaries and 2-1/2" collectors. I am measureing the collector inside diameter? Will these at least work for me or should I just wait and save money for another set? Unsure If I use them and they suck then I would not be able to sell as much as if they were on a unstarted car.