[Mike S]

Correct me if I am wrong. If you restricted flow thru the push rods wouldn't you still see full flow at the lifter? You would just be limiting oil to the valve springs and rockers.

My restrictors for a solid roller are .030 but tapped into the oil feed to the lifters in the block. But this is a mainly strip car with occasional street driving. Myself, I would rather have restricted push rods.

[jhein]

Originally Posted by Mike S

Correct me if I am wrong. If you restricted flow thru the push rods wouldn't you still see full flow at the lifter? You would just be limiting oil to the valve springs and rockers.
.

That's what I was wondering too.

[P@blo]

Spring cooling would be a concern on engines expected to meet warranty or make higher mileage. For engines that see low mileage the trade off to provide more pressure below makes sense.

I am in the water industry and a short neck down does not affect flow much. Is the entire push rod orifice restrictedor just a portion? Also, If pressure increases on a smaller orifice so does flow as they are they are related.

[Singleton]

Originally Posted by Mike S

My restrictors for a solid roller are .030 but tapped into the oil feed to the lifters in the block. But this is a mainly strip car with occasional street driving. Myself, I would rather have restricted push rods.

Here’s a recent video from Powell’s Machine Shop, where he says the same thing about not restricting flow to the lifter, and shows the damage done to a customers roller lifters by restricting the lifter bore. http://https://youtu.be/KRt55CphSqU?is=zWZhVwuzjss33_W_

[Jay S]

Originally Posted by Singleton

Here’s a recent video from Powell’s Machine Shop, where he says the same thing about not restricting flow to the lifter, and shows the damage done to a customers roller lifters by restricting the lifter bore. http://https://youtu.be/KRt55CphSqU?is=zWZhVwuzjss33_W_

That guy in the video had his oil restricted down to about 1 gpm with his .1” orifice before the oil even made it to the lifters. Maybe he had 2 plugs on each bank, maybe 2 gpm at most. Either way, is a lot of restriction before the oil is even close to getting to the top end.