HELP! Valve Spring Issue
HELP! Valve Spring Issue Hey whatsup everyone. I bout the SDPC springs part no SDL1600VS for my LT1. I was told and have read they would work without any issue as they are the same Comp 918s which used to be manufactured by PAC . I know several people run the comp 918 springs on their LTs. My builder is telling me that I didn't have a beehive springs originally and that now I need new retainers and locks since LT valves are different from LS valves. What would I need to run these springs?
I just called SDPC looks like comp cams retainer # CCA-787-16 is the answer to my problems. I could have sworn I had beehive springs prior. I guess that's why you don't assume.
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if you have AL heads you need CCA-4705-16 Spring Locators. the springs will cut into the soft AL head. at the very least use a hardened shim but if it were my car I would use a spring locator.
You can use your 7 degree locks or buy CCA 648-16 locks
This spring wants a installed hight of 1.8". Stock is 1.70-1.75". ideally you need to get the spring pockets machined down but some do install this spring "tighter" than spec. Seat and open pressure will be higher than spec and coil bind "should" not be a problem unless you have a very high lift cam.
Might want to get a valve height tool SUM-900032 to confirm installed spring height
CRN-99473-1 is a great tool to do the spring swap with heads on the car.
You can use your 7 degree locks or buy CCA 648-16 locks
This spring wants a installed hight of 1.8". Stock is 1.70-1.75". ideally you need to get the spring pockets machined down but some do install this spring "tighter" than spec. Seat and open pressure will be higher than spec and coil bind "should" not be a problem unless you have a very high lift cam.
Might want to get a valve height tool SUM-900032 to confirm installed spring height
CRN-99473-1 is a great tool to do the spring swap with heads on the car.
with my current parts (valves, seats, shims) it turns out the springs wont work unless the pockets are machined down. i'd be too much below the recommended install height. with my 574/572 lift cam i would get bind. i'll be going with a different SBC spring that will work with what I currently have. much more cost effective.
needless to say I'll be posting a sale thread for these spring in the parts section.
needless to say I'll be posting a sale thread for these spring in the parts section.
