Cranking compression

Well, yeah, sorta. Are you really a blueprinted 12.1? Compression that high oughtta have a bunch of cylinder pressure. I built a blueprinted 8.5 360 years ago that had 175 PSI. About 2 years later, I had a 12.1 360 in a 65 Valiant that saw 205 PSI. Also, as Adam pointed out, the lobe separartion also has an effect. My guess is your camshaft is ground on 110, but probably 108. That combined with the big duration @.050" is where your cylinder pressure is going. Hard to tell without all of the cam specs, but I'll tell you someone who can help. Dave at Hughes Engines is really sharp. I wouldn't call him though, unless you are absolutely SURE about what your BLUEPRINTED compression ratio is, not what you THINK it is. If you don't really know for sure, my advice to get it DEAD right would be to get the heads off and measure it. It is a race car right? You do want it to go as fast/quick as possible on a given combination, right? then pulling that top end down to get it dead nuts on shouldn't be anything. If you have not measured the compression yourself, that's really the only way. any other way and you'll just be guessin. ....and just a little trivia for you......most people who build and or design their own engines end up overcamming them. That thing should have compression bumping or over 200 PSI. In other words, if it has iron heads, you ought NOT to be able to run pump gas. If you can, sumthin's gettin wasted. BAD. Alloy heads are a little different there, BUT the compression pressure does not change.....only the heat exchange rate. Lastly, WHERE is the camshaft installed? Is it straight up? Advanced? Retarded? Are you SURE? Did you degree it? THAT can make a night and day difference in cylinder pressure.