Bent pushrods in an SBC
#1
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Bent pushrods in an SBC
Hey guys, I apologize for putting this in the wrong section and if it needs to be moved then I understand. I'm in a bit of a bind and could use some help quickly.
With that said...
My old man just fired up my '91 today after putting in a set of forged pistons and new valve springs in it (N20 mishap). The car popped right off and then started to make a lot of noise in the valvetrain. He pulled the valve covers off and found a bunch of bent pushrods. The only thing I can think of is the new edelbrock valve springs in the engine are too much for the stock PR's. I was running stock valve springs prior.
Heres the setup
226/230 110LSA .477/.488 lift
Vortec heads
Speed pro forged pistons ~10:1
Any ideas guys?
Should I just buy a set of chromoly pushrods?
Or do you think there are some binding issues in the valvetrain?
Help
With that said...
My old man just fired up my '91 today after putting in a set of forged pistons and new valve springs in it (N20 mishap). The car popped right off and then started to make a lot of noise in the valvetrain. He pulled the valve covers off and found a bunch of bent pushrods. The only thing I can think of is the new edelbrock valve springs in the engine are too much for the stock PR's. I was running stock valve springs prior.
Heres the setup
226/230 110LSA .477/.488 lift
Vortec heads
Speed pro forged pistons ~10:1
Any ideas guys?
Should I just buy a set of chromoly pushrods?
Or do you think there are some binding issues in the valvetrain?
Help
#2
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are you running a solid type cam? is the valve lash right? loose or tight lash will bend push rods really easy. are the push rods even the right length??? did you check piston to valve clearence? have your heads been milled?.........
#5
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Are you really running a solid lifter cam? What did you have the lash set at? Just because I have seen it done make sure you got the timing marks ligned up right. Pull all the push rods, pick out 2 stock straight ones and set up one cylinder. Turn it over by hand to see what is going on. Make sure you are not running into coil bind. I bet those lift #'s are for 1.5 rockers, do you have 1.6?
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Originally Posted by VORTECFCAR
alright guys, thanks. I'll throw a new set of pushrods in it and start out with a really loose lash. Hopefully it works out!
get an adjustable pushrod tool and check before you just end up bending more, make sure the rollertip or rocker, whatever you have, is centered on the valve tip durring its motion. the roller tip should never roll off the valve, too short and the tip will fall off towards the exhaust, too long and theyll roll off towards the intake