OK to use oiling pushrods on big block?

[EngineerDoug]

Hey guys,

I will need some shorter pushrods on my 383 - perhaps 8.500" - and see that there is a set of 5/16" diameter pushrods on Summit Racing for $35. A lot cheaper than a set of custom pushrods, but they have the internal oil passage. Mopars are solid, as we know.

Any problem using these? I wouldn't think so, but I thought I had better ask before blundering in!

Thanks.

 

[khryslerkid]

Yes the tips are solid.
I think you'll be ok, you're installing the sum6400.
See what the experts say.

Wait for your checking rod. I guessed twice on my build and I was wrong. Used a checking rod and got it right.

 

[mopar 3 B]

The socket ends the same size? If not there will be lifter and rocker ware problems.

 

[EngineerDoug]

Yes the size is the same as Mopar stock. A 5/16" rod with 5/16" ball ends. A mild cam so no crazy spring pressure or valve lift.

Once I get the checking rod I will know length for sure. I am just evaluating my choices for pushrods and would like to save some $$$.

I wouldn't think the oiling hole would pose a problem??

 

[khryslerkid]

I wouldn't think the oiling hole would pose a problem??

I've heard of guys useing them before. As you stated, the spring ratings are close to stock.

My Smith Brothers were $9.00 each. 3/8"x .049 4130 ht
but I wanted the wall thickness for piece of mind with a .488 lift. Also the lenth needed to be 8.900 and useing adjustable ductal rockers, measurements are more critical for the correct geometry

 

[HEMI-ITIS]

They will only oil through if you have lifters that have that opttion. If the lifters do have that option,install a 20 Thousands restrictor in the PR and send oil op to avoid burn cups that that the BBM are known for.
And the restrictors are so you won't loose 15 lbs of op,,,,,,gee,,,,,how do I know?,,,,LOL

 

[lewtot184]

don't worry about it. use them if you want. i thought about using some big block chevy exhaust valve push rods a few weeks. i just opted for adjustables to play with preload. something to think about is those cheapie push rods are cheapie for a reason.

 

[texas69bee]

Well I guess this is the point where I get an education. What determines if you use a push rod with oil through or a solid push rod?
I have adjustable Comp magnum rockers that have an oil passage through them as well as an oil hole where the push rod touches the rocker, oil through push rods with a lunati hydraulic lifter. The oil pressure at idle is low when hot (25psi). 40 when driving, should I be redoing anything?

 

[HEMI-ITIS]

Well I guess this is the point where I get an education. What determines if you use a push rod with oil through or a solid push rod?
I have adjustable Comp magnum rockers that have an oil passage through them as well as an oil hole where the push rod touches the rocker, oil through push rods with a lunati hydraulic lifter. The oil pressure at idle is low when hot (25psi). 40 when driving, should I be redoing anything?

Will your lifters put oil up the push rods?

 

[lewtot184]

Well I guess this is the point where I get an education. What determines if you use a push rod with oil through or a solid push rod?
I have adjustable Comp magnum rockers that have an oil passage through them as well as an oil hole where the push rod touches the rocker, oil through push rods with a lunati hydraulic lifter. The oil pressure at idle is low when hot (25psi). 40 when driving, should I be redoing anything?

you shouldn't "need" push rod oiling with stock internal/shaft set-up, but it shouldn't be a problem either if you do. low oil pressure is probably something else. you may lose a little bit with push rod oiling but i doubt anything near 10-20psi.

 

[texas69bee]

Will your lifters put oil up the push rods?

Yes

 

[texas69bee]

you shouldn't "need" push rod oiling with stock internal/shaft set-up, but it shouldn't be a problem either if you do. low oil pressure is probably something else. you may lose a little bit with push rod oiling but i doubt anything near 10-20psi.

I have a stock oil pump as well. Do ya think changing the pump is necessary?

 

[miller]

Two things affect the oil pressure the pump puts out.

Pressure relief spring, and the gear clearances. You can always pull the relief spring out, and measure it, or replace it.

 

[HEMI-ITIS]

Yes

I can add that adding PR oiling on the exhaust side of my hemi am all 16 on a wedge there was a loss of 15 lbs od OP hot at idle.Installing restrickers in the PR's brought the 15lbs of op back.We did not have the oil hole in the rocker.The wegde had a mellings HV pump and my hemi has a Milodon.
As long as there is no issue with drain back and you have an added volume oil pan,,,should be good

 

[lewtot184]

I have a stock oil pump as well. Do ya think changing the pump is necessary?

check your gauge first to make sure it's accurate. if that's ok then go after the pressure relief spring. it's pretty easy to make an adjustable relief.

 

[texas69bee]

I already add the mechanical gauge, it's 5lbs higher than the dash gauge. What about changing the push rods out to solid? I have to go back in and readjust the preload anyway.

 

[HEMI-ITIS]

The wedges were known to burn cups for some reason so it might be good to keep,maybe put a smaller restricter in the PRs.

 

[lewtot184]

I already add the mechanical gauge, it's 5lbs higher than the dash gauge. What about changing the push rods out to solid? I have to go back in and readjust the preload anyway.

changing the relief spring is much easier. i can't tell you for certain what kind of pressure change solid push rods will make. you'll just have to try it.