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I don't think you'll need one. What manifold are you using? If you're not planning on reving past 6500 then I wouldn't bother with it. And if you are going past 6500 then a solid would be a better choice.
I used to run one on my solid roller, but I had several cam lobe failures/lifter roller failures. I think the additional spring pressure may have helped cause it. Some experts told me I only needed one if I was going to spin it above 7,000 then others tell me I had to have one if it was street motor so the cam would live when idling. Whatever, I do know that it is a bunch of extra parts that can potentially fail, break or bind which I don't like.
Yea but at idle, you get less oil splatter onto the cam, therefore less lubrication - so, the last thing you want is to add a rev kit and increase load on the cam lobes???
Gentlemen, I already have a AFR rev kit installed. Now that I have the intake manifold off, I am questioning its necessity vs. potential problems that it may cause. Upon observation (after about 5 hours engine run time) I noticed that the "aluminum plates" had actually walked a bit; inducing a slant to the rev kit springs :crazy: Hence my original question. The motor will be supercharged (eventually, right now I need to pass CA smog). RPM range should be 5600-6000 RPM (It will have the SuperRam) once in awhile....this is a street motor.
On my BBC, the first set up the rev kit and the lifters were from different manufacturers and it somehow caused the rev kit springs to eat up the aluminum buttons on the lifters putting all kinds aluminum shavings in the oil. After new lifters then the plate moved and rubbed on the push rods. When dissassembled I found one bad cam lobe and visible galling on all the rollers. This is a street car too.
I am building new BBC and I thinking of not using the upper end oil restrictors so I have more splash on the cam. Also, no rev kit and no stud girdle (had problems with them too).
From the understanding I have on the subject, the rev-kits allow you to run higher ramps on the cam without having to incrementally increase the spring pressure on the valve. It also allows the body of the lifter to take the brunt of the forces and free up the hydraulic plunger, hopefully making the lifters last longer.
With that said, if you want a street motor to last longer between builds, then I say a rev-kit is a good plan. But, when you have the issues that were described above...you negate the benefits.
Careful matching of parts is always the best plan when building the motor. It sounds like someone took parts from bin A and matched them with parts from bin Y hoping for the best, and the reliability has suffered.
If you want to run some radical ramps on the cam, then you'll either need to run a rev-kit to help out the hydraulic lifters, or go to solids and have the headache of adjusting them all the time. I guess it all depends on what you want in the end...
From my understanding...rev kits mean more top rpms period. If you are trying to get a few more hundred rpm before valve float, etc then try it, but it is alot of 'stuff' that just adds to the complications...
Under 6500 rpm...a correctly set up head should have no problems without one.
I ran into a valve float situation with my newly CNC's LT4 castings...6000 rpm was the limit! Added more spring pressure (shims) and gained only 100 rpm before the chart took a dive. Come to find out the springs were not being restrained on the head correctly...hulahoop deal.