One of the threads stated the requirements for gm847 springs:

Spring Requirements:
Loads - Closed 115 LBS @ 1.750 or 1 3/4"
Open 336 LBS @ 1.210"


That doesnt seem like very much, yet everyone who runs these cams seems to want kmotion k800s or crane 99893s.

If the above specs are correct, then the k-750 should also work with the gm847 and 1.6RR, and be easier on the lifter, pushrods, retainers, etc.

1.265'' diameter single H-11 spring. Valve lift up to .610''. 130# @ 1.700'' closed, 380# @ 1.150'' open, coil bind @ 1.030''.

Im I missing something? maybe these are not good for high rpm? Im not an expert on valve springs, any articles or info would be appreciated.

thx