cranking compression should i be concerned?

[metcoll]

Hi there did a cranking compression test on my 440...avergage was about 140....is this too low...i have a lunati 240/250  520/547 cam,six-pack replacement pistons & 452 heads,rest of combo is 1/34 headers rpm intake msd ignition set-up 750 proform...car has 4200 stall & 4.56 gears & weighs about 4100lbs...seems to pull very hard up to 6200 rpm,i just it would have at least  170lbs cranking compression...builder told me compression should be @9.7...is this true with the cranking compression that i have...

[Cooter]

240/250 I ASSUME is Duration @ .050 and that's ALOT. Effects cranking pressure. A little too much for a 9.7:1 engine, but will work.

[charger_fan_4ever]

Valve events play a big role. Cam probably has a lot of valve overlap which bleeds off cylinder pressure. 452 heads have a larger chamber too if i recall ? These two factors considered thats probably why your seeing the #'s you are.

[heyoldguy]

What elevation are you at?

[oldkimmer]

.........Thats about right...........kim..........