[k-star]

Ok guys here we go.....

I am building a 440 ci big block chevy. It's 10.3:1 I am going to run a small solid roller in it. The numbers are 246/253 @.050 .663/.680 lift. The motor will probably never see 7000, probably run in the 6500,6800rpm range.

I got the cam from a brand "x" person. There was little info that came with it. I sat down with my degree wheel and got all the valve timing events etc. When i called there tech line the salesman gave me an off the fly seat pressure of 180# for the springs. I looked in the crane and comp catalog for a like cam and they are at 150#, 160# for the same cam. I know right now the trend is to go with lighter spring pressure that will gain you the results that are needed ......

1st question is 150# seat enough for this combo?? What over the nose numbers would be good.

2. If you could have your choice of 2 springs that give you the right seat and over the nose numbers but one was 437 lb / in and the other was 447 lb / in would you use the lighter ,or heaver spring????

Thanks for your input, keith

[machine shop tom]

I would look for a seat pressure of no less that 175lbs and open pressure of 400-425lbs. If you have lightweight valves (.343" stem) and titanium retainers you might get away with a little less pressure.