Thread: Keep Bending Pushrods

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I have an 1992 Chevrolet S-10 Pickup. I recently just put an 1985 Chevrolet 305 out of a camaro into the vehicle. I put a new cam in the motor, along with lifters, and pushrods. I left the rockerarms loose a little, i was going to ajust the rockers while the vehicle was running. The motor turns over fine, none of the rockers are to tight, and like every 15-20 engine revolution, i will bend an exhaust pushrod. Every time it seems to be a different pushrod. I dont no what to do. I tryed messing with the distrubitor and nothing seems to be fixing the problem.

I NEED SOME ADVICE

The last time I had this problem, I was bottoming out the valve springs, from too much lift.

i had the same problem on a 305 found out the cam had way to much lift wha cam are you using?

The rockers may not be slotted enough. The ends of the slots are hitting the studs, and something's gotta give.

Originally posted by S19243H
i had the same problem on a 305 found out the cam had way to much lift wha cam are you using?

Voodoo Camshafts
Camshaft & Lifter Kit
Lift: .489''/.504''
Duration: 268°/276°

If this is the problem, what needs to be done to the cylinder heads. Not trying to spend a hole lot of money.

you didnt say if the motor would run or not. if it want run id be checking to see if i had the timing gears set right. sounds like to me the valve is hitting the piston.

Sounds like coil bind, ask voodoo about the correct springs for that cam, anything over .480 lift with stock springs is iffy, over .500 is no go.

i agree with viking. mine was the performer rpm the 305 dosnt have enough compression for that kind of cam anyway . unless you have alot of money id invest in a 350 or stay around 440 to 450 lift from my experence

I just went through the exact same problem. Same cam too.
I did not have enough retainer to guide clearance. Even though the measurement should give about .570 clearance and the cam with 1.52 rockers gave me the .060 @ .510 lift the umbrella seal are .100 THICK!!. Not enough to make noise but just enough to bend a rod here and there.

I bent a couple pushrods in a 327 I bought that someone had installed a high lift cam in. Not only did it bottom out it scraped some of the aluminum off my roller rockers in the process.

yep i'd check on the springs more than likely thats your problem.... i've always matched springs to cam to be positive.... plus the better the match the better your valves will open and close properly and be able to wind up quick and run steadier.... i've never bent a push rod.... but i'd put a few thru a valve cover once