black06g85

iTrader: (6)

Just finishing up putting my motor together and going to set the rocker arms. On all the exhaust side is compressing the valve. Running standard 5.3 pushrods for now. Intake side is fine but on all the exhaust is compressing slightly. Anyone run into this issue before? Trying to see if i can get an idea before i tear this thing apart again

KCS

iTrader: (20)

Compressing the valves? Have you made sure the lifter is on the base circle of the cam and not on the actual lobe?

black06g85

iTrader: (6)

Of course. Built a few sbcs before. Just never ran into this yet

black06g85

iTrader: (6)

And yes compressing exhaust only

chevybowtie

iTrader: (16)

I believe the ls6 cam uses smaller length pushrods. I believe 7.350.

KCS

iTrader: (20)

What lifters? It sounds like somehow the pushrods are long enough to eat up all the travel in the plunger of the lifter and start compressing the valve spring, which is REALLY wierd. What else is done to the engine, heads, what cam, etc?

bww3588

iTrader: (49)

They use the same length push rods. The ls6 valves are longer and the cam is ground on a smaller basecircle. If anything, I would think the push rods would be too short using shorter ls1 valves and a smaller basecircle cam.

To the op, have you verified the lifters are not pumped up fully? Are you using the EOIC method to set the valves?

black06g85

iTrader: (6)

I have to check next weekend when i get back to the shop. But just left them sitting in a bucket of oil for a day before installing. Just rotating cam to top dead for each cylinder and tighing down and checking vave tip pattern. But on all of them exhaust is hanging open on compression. I would think if anything pushrods would be too short. But its and02 ls6 cam stock 5.3 lifters andpushrods unmilled 317 heads ls6 intake nothing too special. I dunno i dont want to pull the motor apart again lol.

bww3588

iTrader: (49)

Don't soak the lifters. That's the worst thing you can do.

KCS

iTrader: (20)

Pick a cylinder and turn the crank until the intake rocker starts to close on that cylinder, then try the exhaust and see what happens.

black06g85

iTrader: (6)

Already did it doesnt change. Guess ill pull the lifters and see what happens after i bleed em down

black06g85

iTrader: (6)

thankfully its still sitting on the stand, hopefully knock this out this weekend and start putting the car back together

JT86SS

Any updates? im curious to see what the issue is.