what is an ideal, pump gas/nitrous friendly DCR? this is for an LT1, would 10.5:1 be too much? i understand altitude (guessing density altitude) is a factor in it, so it will vary from day to day. but i used a calculator for it, and put in 0 feet for sea level and got 10.8:1 DCR, using 11:5 SCR piston, 5.7 rod, 3.48 stroke, 4.030 bore, 0psi/boost

 

If your DCR is too high, then you are using the wrong IVC, you need to use the actual closing point not the .050 numbers.... look thru here on DCR problems in the search function and you might find something to help you out.

Bret