[ponjohn]

This is one subject that seems to confuse me based on the differing opinions.

I was reading the Butler website and on the Johnson lifter page, it says " they recommend a .020 or .040 restricted push rod.

Why would you ever restrict oil with a hyd roller?

I do understand why on a solid roller but there are so many different opinions on how much it should be restricted.

[steve25]

Does Butler state this for both street and race?

A hydro lifter ( be it roller or flat tappet) needs a certain above minimum of oil to be able to adjust for any valvetrain clearance that might take place which is why ( if you choose to ) the plunger is adjusted down from its max full travel point that it has.

The roller of any roller type lifter can live with far less oil then a flat tappet type.

It also follows that a full roller rocker can do the same , the caveat is how much oil is needed to keep the valve stems lubed up and to cool the valve springs.

For drag race use the motors are only run for short periods and way up above the rpm of a street motor, so they can get away with less top end oil getting there.

This reduced oil volume needed does wonder for the main a rod bearings in the engine.

Also some solid flat tappet lifters ARE self restricted and there may be some hydro roller lifters that are also, but I am not sure on that .

Here’s what HO racing recommends and with my mostly street motor that had a solid roller cam and full roller rockers I drilled out my lifter restrictors I used in my block to .055”.

Back then the first roller lifters that I used where made by Comp Cams,
and I never had an issue with my 455 that would get rev’ed to 6500 .

[slowbird]

I would never restrict the topend on a street engine. Rockers and valve springs need that oil for lube and cooling.

[steve25]

Just to add to post #2, my roller Cam’ed 455 was a street motor mainly and had a ton of highway miles on it.

[ponjohn]

https://butlerperformance.com/i-2445...tegory:1459682

Scroll down.

[steve25]

Ok, so i looked at what the Butler site says about those lifters and there calling for a .020” to .040” restrictor.

Here’s what Pontiac recommended for the early SD motors and the RAV due to there use of solid lifters .

What you need to understand is that unless a solid or roller type hydro lifter is made with a dedicated restriction ( like the solid non roller Chevy edge office type) then they need to be restricted.

Why these that Butler sells are non restricted yet the are a hydro type I have no clue.

I then suggest you call there Tech line or send a email to the manufacturer of those lifters to get an answer.

If they have to be used with restricted push rods then I would go with .040” and be on the safe side of oiling the top of the motor.

[zippy]

So restricting pushrods on a street car is not advisable?

[jhein]

I went throughs this with my motor. I missed the part about the restricted pushrods, realized it after the fact. I don't remember exactly but I think Butler said that excessive top end oil could potentially starve the crank. I talked to the Johnson people and they said they were not aware of any such situation with those lifters. My engine builder also dismissed it. So I decided to leave it alone. Would it be correct to assume that if you had a problem that you would see low oil pressure, maybe especially at higher RPM? If so, I definitely don't have that.

[jhein]

Here's a link to the other thread:

https://forums.maxperformanceinc.com...d.php?t=865235

[SRGN]

It comes down to balancing flow, every engine is different. Using an LS as an example, they hemorrhage oil internally, you need a bigger oil pan than most older engines (6 quart is the smallest factory capacity) since the oil has to get up to the top and if you don't have enough oil, pan will run dry before it all drains back down. Limiting flow up top is more critical with an engine that doesn't leak a lot internally, and drains back more slowly. This is one of the reasons for thinner oils in some engines. Everything is obviously more complicated than this simplified version, but with a deep pan and pickup I'd be less worried about restricting flow above the rotating assembly. Especially if the drain passages have been properly modified to let the oil flow back to the pan.

[Dragncar]

I ran .030 restrictors in my 455 and drove it on the street and to the track for years. No problems. sft.
You can get a lot of oil through that .030 hole. If you have a issue with it run a .040-.060 hole.
No lifter company is ever going to tell you to restrict oil to their product, ever. All they care about are their lifters.
They do not care a lick about your main and rod bearings.
I see it all the time in industry. A sprocket might have a keyed tapper lock holding it to the shaft. And the maker says if we use Anti Seize on it it voids the warranty Never mind in the 35 years of doing this have I ever seen one returned for warranty issues. If we have a problem, I cut them off with a torch. And you can ruin the very expensive and hard to change bearing behind that sprocket with a torch. .
So I run restrictors on my Pontiacs and Anti Seize on my tapper locks.

[scott70]

So I just installed a HR in my street engine,,, evolution lifters and did not restrict the pushrods even though butlers recommended it. What’s the average size hole in a standard aftermarket pushrod?

[chiphead]

Great questions. Is the oil metering to the pushrod a lot different between a HR lifter and a HFT lifter, for the same oil weight?

I know a HFT will put a LOT of oil up top on a Pontiac. Is all that oil flow needed to cool the valvesprings? Is it different when using the shields vs using a modern Viton seal? Seems like all that oil increases the chance of oil pulled past guides or valvecover oil leaks. Just on my stock type 400 with the valvecovers off, the oil will overflow the heads above idle. The guides are swimming in oil.

Is the point of restricting the pushrods to limit oil starvation in the pan? What about a case where you can keep the pick up covered with oil?

[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.

[ponjohn]

I sent a message to Johnson.

[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.

[steve25]

I am 100% sure that whoever the hydro lifter manufacturer may be does not give half a dead Rat’s ass to any problems oiling wise that might take place from less oil flow to the top end due to running a restricted push rod.

That being said I am also pretty sure that if I made a hydro roller lifter that I would not want a restricted lifter bore feeding the lifters I manufacture, but if I DID make such a lifter I would feature it prominently in my product advertisement.

I guess I am saying it’s best to contact the manufacturer to see what they say and to try and gain insight into why Butler says what they do.

[Jay S]

For HR lifter’s the reasoning to restrict the oil has more components to it than other lifter options like mechanical rollers or HFT’s. The restricted pushrod oiling is used sometimes to help nurse the lifter bleed rates by making the high pressure chamber of the plunger fill a bit more before oil is sent to the top end. Retrofit HR lifter’s will often loose some oil pressure against other lifter options, the restricted pushrod is used partly to help overcome that also. Most applications I have seen swapping from a HFT to a HR lifter it is common to have around a 5ish lbs drop in oil pressure using the exact same oil system and bottom end. Over flooding the top end of the engine with oil is not the reason I restrict the oiling on HR’s on most combo’s. It depends on how tight the bottom end of the engine is, pressure is built by resistance to flow. Sometimes a restriction is needed to feed more oil to different components, it isn’t all about keeping something from getting flooded. I prefer the .040” restrict pushrod on the HR lifter to help overcome issues in the lifter bores and even out bleed rates, and helps get some of the oil pressure losses back for holding the bottom end of the engine together better.

A .040” restrict pushrod is really barely a restriction, that should never cause an issue anywhere. I’d personally pick that no matter what HR lifter was used. When you get down to the .020” range, that is a little different story, that is probably best with a 80 psi pump and the lighter weight oils. We don’t use the .020 or .025”.

[chiphead]

Originally Posted by Jay S

For HR lifter’s the reasoning to restrict the oil has more components to it than other lifter options like mechanical rollers or HFT’s. The restricted pushrod oiling is used sometimes to help nurse the lifter bleed rates by making the high pressure chamber of the plunger fill a bit more before oil is sent to the top end. Retrofit HR lifter’s will often loose some oil pressure against other lifter options, the restricted pushrod is used partly to help overcome that also. Most applications I have seen swapping from a HFT to a HR lifter it is common to have around a 5ish lbs drop in oil pressure using the exact same oil system and bottom end. Over flooding the top end of the engine with oil is not the reason I restrict the oiling on HR’s on most combo’s. It depends on how tight the bottom end of the engine is, pressure is built by resistance to flow. Sometimes a restriction is needed to feed more oil to different components, it isn’t all about keeping something from getting flooded. I prefer the .040” restrict pushrod on the HR lifter to help overcome issues in the lifter bores and even out bleed rates, and helps get some of the oil pressure losses back for holding the bottom end of the engine together better.

A .040” restrict pushrod is really barely a restriction, that should never cause an issue anywhere. I’d personally pick that no matter what HR lifter was used. When you get down to the .020” range, that is a little different story, that is probably best with a 80 psi pump and the lighter weight oils. We don’t use the .020 or .025”.

So if I understand this right, if you build a motor with a HR and the lifters make some noise, first try a .030-.040" restricted pushrod? I guess the restriction in the pushrod helps the lifter metering keep oil below the plunger?

Keeping oil in the lifter to crutch bleed rates makes some sense. The spring pressures with HR are higher than HFT, so I can see issues with keeping the lifter plunger pumped up at lower engine speeds. This could reduce the clacking at and above idle.