4.00" bore, 3.48" stroke, .015" shim gasket, .020" in the hole (what I've measured on two blocks, give or take a few .001s"), 56.6cc (including the 4v reliefs) = 12.0:1.

 

I thought stroke was 3.75 I'm getting 11:25 http://www.wallaceracing.com/cr_test2.php

 

Stock block has a stroke of 3.48"...

 

We can play with STOCK deck clearance numbers all day, (I also have measured two (2) LT1 blocks, and the deck clearance varied from cylinder to cylinder by .002" but averaged that prevoiusly stated .025"), but ...... how can you TOTALLY ignore that 7cc of stock piston relief volume???

 

the chamber volume is 56.6 + 7cc he figured 56.6 with relief cuts. This all just seems to be a numbers game in the end time slip tells it all.

 

I stand corrected, but the stock volume is 4cc. With those corrected figures we end up with 11.6:1 - still FAR better than the 10.6:1.

That's an easy 10-12whp difference.

 

I'm getting 11.4 but we can go at this all night, in the end it will come down to who has a better calculator and least amount of beers.

 

Well, we are having a great discussion here, but ........ I have to respectfully disagree.

While I haven't personally cc'd them, I've looked at those four(4) STOCK piston valve reliefs often enough, and believe me ........ they are bigger than 1cc each.

 

I figured they are about 6-8 cc and it makes a big difference in the outcome.