Topic: Billet pushrods?

[slideways]

Running a 23hp Vanny. +.100 stock cam, 2bbl methanol carb, stock valvesprings/rockers/pushrods. Billet rods/aftermarket pistons.

I've found billet pushrods that claim to be stronger than stock 3/16" steel ones. Says they grow at the same rate as the block or something... are these worth it turning 6400rpms? We have to run stock rockers and some type of valve springs that we dont know the specs of.. obviously a cam manufacturer recipe.

Thanks for the info

[iused2mow]

most people would go with an upgrade to chromoly just because they are the strongest i cant help but think that at higher rpm the pushrods would fail. i would say go chromoly

[fordman21]

I'm not sure about growing at the same rate as the block but I've had really good luck with the billet aluminum pushrods. If your only turning the engine to 6400 the stock steel push rods will also work fine.
The chrome moly push rods are bullet proof, but your going to need a lot more valve spring.

[George Herrin]

Yup I concur with Fordman at 6400 stock steel pushrods are all you need. I have raced the vannies for many years turning em 8 to 9000 using only the stock steel push rods and never had a failure.

[slideways]

I guess the other question i have is that is there any hp benefit from changing out the steel ones? Or is it not worth getting caught with these in there?

I hear of a few bent pushrods in our motors. One guy had a few in a few races.. which raises a few eyebrows about what he's doing to his mandated valvetrain. The only thing i can see that would bend them is coil bind... i have (4) .100 shims in my springs and cant see any coil bind. Any more than what i have and there is no space left in the spring guide to put another shim in and still have it recessed. It could float around under the spring against the head and probably cause havoc... i suppose.

Thoughts?

[fordman21]

If someone is bending steel push rods, I can assure you something is wrong, the engine is experiencing coil bind or the retainer is hitting the valve seal or guide. Even with an unheard of amount of valve spring pressure for a vanguard you shouldn't bend those push rods.

[hiflyer727]

What exactly is "coil bind"?  Thanks

[briggsracer1892]

coil bind is when the spring is fully compressed befor the valve is fully open therefore it would bend the pushrod that way.

[hiflyer727]

What would need to be done to correct such a situation?

[fordman21]

There are a few ways to get rid of coil bind.
-you could use a spring with less coils
-you could use valves with longer stems
-there are retainers that have a recessed center that allows the spring to sit higher.
-you could machine your spring pockets
-remove some spring shims if you have them.
If your retainer is hitting your valve seal or guide.
-remove valve seal and run the engine without them.
-machine down the valve guide until you have at least .050" clearance from your retainer to your valve guide at max lift on a vanguard.
All these modifications are assuming you have the proper spring pressure.