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I am looking for the combustion chamber size. I also need to know if the eccs redtop and silvertop heads use the same cumbustion chamber setup. Lastly, are the pistons the same? I am trying to figure out the compression ratio that I will get just from the head swap, then if I can get any more out of it.

I did do some searching.

Edited by Driftnuttz
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Google says they bolt together and the bottom end is identical.

Thus if you look up the CR of the red and compare it to the CR of the silver you will find the difference.

You could also do such things as review an FSM to see if the bottom end for red and silver is different in any way. Again CR will tell you the rest.

Google says they bolt together and the bottom end is identical.

Thus if you look up the CR of the red and compare it to the CR of the silver you will find the difference.

You could also do such things as review an FSM to see if the bottom end for red and silver is different in any way. Again CR will tell you the rest.

I am looking for specs, how big is the dome on the pistons (red and silver), how big is the combustion chamber of the red and silvertop heads, are the head gasgets the same thickness. things that I cant find on google, and would not be in the fsm. I know people say the bottom end is the same, but I am wondering if the pistons are the same and if the heads use the same cumbustion chaambers. I know the heads are not made from the same cast, so I am wondering what esle besides the intake runners are different.

You cant just look at the CR of the redtop and silvertop and say it will get X CR. There is simply too many factors involved in getting X CR.

Thanks for the response.

If the pistons are the same, and the CR is the same. Then it is safe to assume the chamber CC is also the same, which I believe is what your worried about?

If im right and your only worried about the resultant CR, then prove the pistons and HG are the same. The reason I advise to do it this way is because I do not think you will find information on the heads actual difference.

If the pistons are the same, and the CR is the same. Then it is safe to assume the chamber CC is also the same, which I believe is what your worried about?

If im right and your only worried about the resultant CR, then prove the pistons and HG are the same. The reason I advise to do it this way is because I do not think you will find information on the heads actual difference.

Not really worried about the resulting CR, I am looking to up the CR. I just want to know what the CR should be with just the head on the block. Sometimes stuff changes, and considering they used a completly different cast to make the head I thought they might have made a change or two to the cumbustion chambers and pistons.

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