Can anyone tell me what the cr will be if I used a l92 stock bottom end and a set of 243 heads and what size head gasket dont want to go past 11.1

 

With stock .052 head gaskets you're at 10.74. Going to a .045 HG will put you at 10.93, which is as close as you might want to get.

 

Called tsp to buy gaskets today and was told with the stock ls3 gasket .51 my cr would be 11.2 ?

 

Check the compression ratio calculator on Summit's site.
The piston has 3cc reliefs. TSP might have not considered that.
243 heads have 65cc chambers, which is 5 less than the L92's 70cc.
It came out to 10.77. I figured on the gasket at .052 before. I used .051 this time
With a flat top piston it would be 11.15:1. TSP rounded it up

 

I was under the impression that L92 heads had 68.5cc combustion chambers. Here's is another site to calculate static compression.

https://speedmaster79.com/tools/engi...pression-ratio

 

Summit's LS specs site lists the L92 (and all other 6.2's) chamber volume at 70cc

 

They are 68.5 cc chamber. No disrespect to Summit, but their numbers aren�t always legit. I�ve seen a couple different piston sets, where they have listed the cc�s wrong, with my Wiseco set in my 434 being one of them. Thankfully Tony pointed it out to me while we were setting up my compression numbers. I personally check numbers elsewhere.

 

Yeah just quoting them as a source. I would hope Summit would update some of their data once people find discrepancies. I've seen other potential errors in their engine data.
Thank you for rectifying the head spec!

 

WallaceRacing.com has probably 300 calculators from engine and 1/4 and 1/8th mile weight changes ……….etc every calculator You can think of and more free. Its pretty cool