stock rockers on .621 lift cam
#1
stock rockers on .621 lift cam
so how much lift can the stock LS1 rockers take. i know that they are pretty good, but can they take .621 lift without wrecking the valves or hurting the rockers? the springs i will be running are EHT .675 springs that are rated at:
1.800" = 161lbs
1.150" = 472lbs
is this to much spring pressure, together with a high lift cam for the stock rocker arms? if so then i need some suggestions for some aftermarket roller rockers. i was looking at the yella terra ultra lights.
-Thanks
1.800" = 161lbs
1.150" = 472lbs
is this to much spring pressure, together with a high lift cam for the stock rocker arms? if so then i need some suggestions for some aftermarket roller rockers. i was looking at the yella terra ultra lights.
-Thanks
#2
I have seen people use stockers with more lift,but I feel you should install the compcam trunnion bearings for stock ls rockers.you can get them at TSP.some told me the stock needle bearings aren't caged,and the comp cams are caged.they don't come out when abused.
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i agree with the idea of the ugraded trunion kit. im in the process of doing a full motor rebuild and am doing the upgrade and cam. its really easy and when you pull the stocker rockers apart you will see how cheap they are.
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stockers geometrically are great. if you upgrade the trunion and be sure the wipe pattern is ok and they are setup good you should be fine. If you were concerned with breaking a rocker, you wont.
#13
Personally, I have had stock rockers lose their bearings while using higher pressure springs. Does it happen to people often, no. However, it does & can happen. The best thing to do is to upgrade the trunion, as advised in several comments already. If you were to lose a trunion cap, you'll be forever trying to make sure that every little needle bearing is found @ the very least.
Ntimid8r7, I dig the Al Bundy pic.
Ntimid8r7, I dig the Al Bundy pic.
#16
You check w/ a fixed lifter & a pushrod length checker or w/ a stock lifter & soft valve springs installed for checking. Wipe pattern should be centered on the valve tip. It is adjusted by changing the pushrod length.
#17
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Pushrod length won't effect the wipe pattern on the stock rockers because the pivot point is fixed relative to the valve stem.
You need to either shim the rockers up to move the pattern to the exhaust side or mill the rocker stand (aftermarket required here) to move the pattern to the intake side. With stock rockers it will be wide. I think you will find the rockers need to be lowered because of the lift you are running and therefore you will need an aftermarket rocker stand that will allow the height to be altered. This is not a place to cut corners.
There is a third method for checking, use check springs and a dial indicator. Rotate the rockers by hand through the required lift. This way the motor doesn't have to be rotated. This can also be done with the heads off the car. I find this method to be the easiest as it allows quick changes to setup with minimal work until you find the correct height.
You need to either shim the rockers up to move the pattern to the exhaust side or mill the rocker stand (aftermarket required here) to move the pattern to the intake side. With stock rockers it will be wide. I think you will find the rockers need to be lowered because of the lift you are running and therefore you will need an aftermarket rocker stand that will allow the height to be altered. This is not a place to cut corners.
There is a third method for checking, use check springs and a dial indicator. Rotate the rockers by hand through the required lift. This way the motor doesn't have to be rotated. This can also be done with the heads off the car. I find this method to be the easiest as it allows quick changes to setup with minimal work until you find the correct height.