problem installing new valve springs!

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Thanks for the reply. I am currently running stock stamped steel rockers. Lunati lifters and stock push rods.

Maybe I don't understand the coil bind formula. According to the Comp Cam FAQ you get total lift by (installed height-coil bind-.060) .060 being what is left at max lift before coils touch.

With the 60402 cam the exhaust lift is 494. My valves are within .015 of 1.650. So if I just use the 60402 spring spec. 1.650-1.125-.060=0.465
IH CB Safety Tot Lift
So that would say that either side of my cam would be in coil bind.

Am I doing the math wrong? I do have a set of Isky dictile rockers I plan on using in the future.

Thanks,
Dan...
 
Thank you Moper. I will look closely at your suggestions and do some more research. I was aware that I did not know what I did not know (if that makes any sense), so I simply decided to ask.

FYI, I plan to use the stamped steel rocker assembly from the 318 heads that were on the engine before I got the 340 heads. I do not want to change any of the retainers.

moper said:
Claudius, Look at more than the pressures... The installed heights and spring rates and especially the coil bind figure are what you need to compare apples to apples and these vary from part number to part number and manufacturer to manufacturer. It's easier for me to just use what the cam guy wants... and in some cases, a spring may look like it will work but due to something else (like safe harmonic range, rocker ratio or overall valvetrain weight, too large a diameter of wire in s single spring, etc) the other spring may not work as well, over the full rpm range, or for as long. So the right (or usable) spring has nothing to do with compression, type of head, or block. So for the two cams listed I'd go something like Comp 901-16 would work for the Lunati 401 , but the 402 IMO needs more and that one the 942-16s. Unless your goign to buy new retainers to raise the installed height I dont think the 972s are the best way to go. They have a coil bind height of 1.195. If they are isntalled at the std 1.650 height with a std retainer, the spring will bind at .455 at the valve.
Click to expand...
 
I installed comp cams 942 springs on my heads, no shims, with the Lunati 402 camshaft and lifters with stock rockers and push rods. They work well. I have a measured .042 room before coil bind and can now rev to 6k without valve float.

Only issue now is dealing with lifter pump up. I installed a HV oil pump and I am getting 90lbs at 5K+ rpms.

Dan...
 
I have the 60403 cam with Comp 942 springs. I haven't drove it enough yet though to give you a fair opinion.
 
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