I just calculated compression ratio in LS/VTEC I'm bulding. I used c-speedracing on-line calculatior. The result was 11.6:1, when I used B16A with B18A and pistons from B16A USDM.

My question is: Is this compression too high for this engine to make reliable or I don't have to worry about it t all? Are there any necessary additional upgrades to the hybrid engine I shoud make to be secured with such compression?

 

I don't think 11.4 is too high at all. I just met a guy 2 days back that has an LS/VTEC with CTR pistons with a GSR head that has been milled .25 thousanths. He's running 12.4:1 C/R. He runs 92 octane and doesn't have any problems.

Of course if you can go with somewhere around high 11s or low 12s C/R then do it. All you have to do is back the ignition out a little if you notice that you're pinging. However, I still don't think you'll have a problem.