Pushrod length with gn1 heads ?

[434nova]

What is the average length on pushrods with gn1 heads ? Mine are 8.375 Isnt that really short for that combo ? I have read where people are running 8.850 or so. What is the effects of running short pushrods ? Car 20,000 miles with these pushrods on them. Seems to be running good besides all my valvesprings have broken inners , trying to track down what would cause that and noticed my pushrods are short , maybe it has a connection ? Thanks

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[StageII86]

Aluminum heads? Those sound short, I believe many ran ~8.550" (+/-) with something like a 853 lifter and roller rockers on all out-of-the box stuff. But we have no idea what lifter and rocker setup you run, or if your valve heights have been altered or anything like that, so the length you offer is irrelevant. Broken springs is bad, definitely replace those. Check your lifter preload - that's all that really matters in determining pushrod length.

When/if the preload is correct, it could be a good idea to double check and insure the rocker tip is staying somewhat centered over the valve tip...no idea if that's an option with your rocker setup or not.

 

[434nova]

Not sure on lifters I bought the car with the motor already built. Rockers are t&d 1.65 ratio. Yes heads are aluminum. Will dobon rocker preload and also on the valve tip.

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