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What size Oil Restrictor

2quick

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I'm having an issue with very low oil pressure at idle (like 9psi hot) after installing T&D Rockers. At 3,000 it's up to around 45 and I'm sure there is a ton of oil getting to the head. I am running 440-1 heads that are full time externally oiled. Before the T&D setup I was using the crap Indy Black rockers and tore the bottom out of an intake rocker. But even then idle oil pressure was maybe around 17psi hot. I do not currently use any restrictor in the lines but think this may help. My question is what size restrictor to use, .050 - .045 - .039? Been looking around and don't really see what I need. After shutting off the motor you can actually hear the oil running back into the pan.

I found this restrictor from INDY and I'm going to make it myself but I don't see what size orifice they use. Also here's a pic of the Broken Indy Rocker and New T&D Setup.

restrictor.jpg IMG_5371[1].JPG IMG_5363[1].JPG
 
Is this a race deal ?
.045" to .050" is lots, you just don't require that much Oil for lubrication up top, it's more the cooling of the V/Spring the Oil provides you should be concerned with IMO, especially for street usage ? if you are attempting to run 200+ Lb Seat Pressure/550 Lb/in rate Race Roller profile V/Springs on the street, which it looks like you may using ? by the look of the broken Black DOVE Rocker ?

17 psi at idle HOT ?
What weight Oil and what Oil Pump ? std or high volume ?
 
I am far from an expert on this, but it would seem to me that you might be increasing oil pressure at the cost of oil flow with a restrictor. While 9 psi seems a bit low, but I'd bet it is enough to get oil to all the internal parts at idle. I'd be much more concerned about flow at higher RPM with a restrictor.
 
Is this a race deal ?
.045" to .050" is lots, you just don't require that much Oil for lubrication up top, it's more the cooling of the V/Spring the Oil provides you should be concerned with IMO, especially for street usage ? if you are attempting to run 200+ Lb Seat Pressure/550 Lb/in rate Race Roller profile V/Springs on the street, which it looks like you may using ? by the look of the broken Black DOVE Rocker ?

17 psi at idle HOT ?
What weight Oil and what Oil Pump ? std or high volume ?

Street Driven, Milodon Pump, Externally oiled Mildon Pan, 235lb seat 650lb over the nose @ 1.910 installed PSI Endurance Springs, Current Orifice feed hole is .107
 

That may be part of the Oil Pressure problem right there ?
We've experienced problems with the CROWER edm trunion feeds literally DUMPING a ton of Oil OUT and AROUND the bottom of the Lifter Body as opposed to anywhere else it's intended to go ?
The system is supposed to pressurize the edm hole maintained opposite the Lifter Oil gallery... the "clearance" in the Lifter Bore itself being the metering and why they want TALL Lifter Bores ?, suffice to say in our experience anyway, you can NOT run that Lifter without BUSHING the Lifter Bores in any block ?
So I must assume here:
1.) you are running a BUSHED Lifter Bore stock/aftermarket Iron Block ?
or,
2.) KB or other Water Block aluminum UN-Bushed ?
Which is it ?

Do I get a Kewpie Doll for guessing you V/Spring rate by the look of that poor Black DOVE Rocker ? LOL
That DOVE was waaay outa it's league for what you are attempting 300#'s ago !
 
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I usually set them up at .060.

I’d start there, and then if it hasn’t improved the pressure enough try .050.

I’ve never had an oil pressure problem using .060 destructors.

I believe the ones from Indy are .040.

And yes, as mentioned above, certain lifters in certain blocks can really dump some oil around the lifter wheels when the lobe gets near full lift.
If you have the valley cover with the removable panel, and look in the valley around the lifters while priming and turning the motor over at the same time....... you might be unpleasantly surprised at the amount of oil hemoraging out around various areas of the lifters.
 
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IF you are NOT running Bushed Lifter Bores with those CROWER Lifters ?
IMO,
before you do anything else..... pull the Intake and run the Oil System with a Oil primer shaft(PRIME the Engine obviously), and WATCH around your Lifters ?
If you see your Oil Pressure coming out around the Lifter Bores ? or between the Lifter Cup and bottom of the Pushrod ? Squirting out like sh*t through as goose
you have your answer......
 
Years back after my second lifter failure with the Comp 829,switched to the AMC lifter that had the pressurized oil to the needles and had pushrod oiling.Even though I have shaft oiling I sent oil up the exhaust PRs for a little extra oil on the spring but with no hole in the rocker adjuster.Did the same change on my friends big wedge and both engines LOST 15 lbs of OP.Installed restrictors in the pushrods and the OP came right back.
After the 1st failure my entire oil system was contaminated.Was using Fram HP filters.
The Milodon oil pump flows 19 GPM @ 3K rpm and about 21 GPM at 7K rpm.The Fran filter flows 12 to 14 GPM,so when 19GPM hits the FRAM filter with a bypass,the bypass opens and your not filtering diddley!!After that expensive lesson I went to the Moroso filter that has no bypass.Now I'm using a System 1 and a pair of aluminum heads that were sitting on a shelf for over 20 years!!!

117-1729_IMG.JPG 117-1731_IMG.JPG 117-1733_IMG.JPG 117-1734_IMG.JPG 117-1735_IMG.JPG
 
Indy EZ-1 heads - internally oiled BUT full time oiling. Harland Sharp roller rockers - so you know there's a lot of pressure loss there! I use a standard pump - not high volume with a Milodon pressure adjuster on the pump. External oil feed pump cover. I had what I considered HUGE oil loss around a set of roller lifters and switched to a set of Cranes that have the roller wheel shrouded to prevent uncovering the galley at lift. I put .062 restrictors in "just in case". Have only primed the motor at this point and have good oil pressure. Its amazing how much flows out around the lifters though !!
 
The fact that the lifter May be a problem is news to me. I spoke with Crower in depth about the need for bushed lifter bores and they assured me they were not necessary in my application. I went with the Crower lifters to get away from needle bearings and they weren’t cheap like 1200 bucks not cheap! But I feel like I’ll try the restricters first as like I said when the INDY Rockets were on there Oil pressure was up 10 from the TD stuff.
 
So I just got the phone with Crower and the guy over there that according to him only builds and owns BB low deck mopars reassured me that those lifters are designed to work in both stock unbusched bore and also tall bore aftermarket blocks. He did go into checking the factory notes for out of round and stated they required .0025 - .0030 of clearance. He also stated that he has never seen a big mopar lifter bore that was actally round. “Never not once” and if the oil pressure issue had a thing to do with it that would be it. Also he wanted me to check the base circle on the cam to make sure the lifter wasn’t sliding down to deep unshrouding the oil passage. He also mentioned that because it’s not a closed loop system and the way the shaft rocker full time oiling is designed, that the pressure drop after the engine internals pumping out to the less Restrictive shaft oiling Will actually show up pressure drop at the gauge but the actual internals are seeing more pressure. So by adding restrictors I will increase the pressure to the gauge but according to him may not be necessary as the internals are at a higher pressure to begin with.....Or Something like that. I get what he saying it’s just hard for me to explain it. Pressure drop against a orifice size, Cohesive of friction, stars aligning, full moon, I don’t know!
 
I can’t really answer your question. But from past-experience, my last 440 would go down as low as 10psi at hot idle while it did bother me some I ran it for 5 years that way and when I sold the engine I opened it up for buyer to inspect and it looked great. I would kick it in to neutral at stop lights to up the PSI to 15ish. 3500+rpm it would be above 60spi.
 
I set one up at .040 with t&d’s. Haven’t had it apart to see how it looks. The Indy rockers on my rr needed .060 to get enough oil
 
Frankly, the description you gave from what the guy at Crower said makes me scratch my head.

The picture would be made crystal clear as to whether you have a problem with those lifters in your block by doing like Bob and I said.
Prime the system and watch what’s happening in the valley.

If you don’t see oil gushing out from below the lifters when they are near full lift(and you have to check every one), then you’re not having that problem.
But...... I’ve seen a stream of oil as big as my thumb run out from below a roller lifter on one of my 440 blocks....... and that motor actually had decent oil pressure.
If it would have had a few more holes that leaked like that....... it would’ve been a problem.
 
Frankly, the description you gave from what the guy at Crower said makes me scratch my head.

Me too !! Whatever the pressure reads on your gauge is the pressure the bottom end is seeing - no more. If its says ten at idle, that's it. The only ways to get an increase in pressure anywhere are 1) increase volume or 2) restrict the flow downstream of where you want the increase or 3) use thicker oil. Decreasing clearances falls in the category of "restricting". As for his comment about round lifter bores, that's a strange one. Just how close is he measuring tolerances ?!?! I don't see how they can be out of round by any significant amount - they are bored then honed. And "core shift" doesn't come into play once the block is out of the mold and cooled.
 
I’m going to pull the valley plate cover and take a look. But (and don’t take this the wrong way) after 3 calls to manufacture and being told the same thing by three different techs, one has to assume they have done this before and it works! I mean Crower is a pretty reputable company that’s been around a long time, and according to them they have thousands of these lifters in stock block, unbushed lifter bores, without problems.

But, that’s the reason I installed the valley plate with the inspection cover, so I will look at it tomorrow and hope for the best.

At the end of the day I think I’m still going to put a .050 restrictor in the heads. All I really want is 10 more psi at idle hot. Anything over idle is good. I get like 65psi @ 5000rpm.
 
The rollers I initially used had no shrouding around the wheels - much like the ones's in your photo. With a .600 lift cam they were exposing the galley at full lift. The Cranes I bought have the shrouding on one side of the roller - the side that sees the larger cross section of the galley at lift. The shrouding goes almost half way down the wheel. Even the other side has more shrouding around the wheel than yours.
 
The rollers I initially used had no shrouding around the wheels - much like the ones's in your photo. With a .600 lift cam they were exposing the galley at full lift. The Cranes I bought have the shrouding on one side of the roller - the side that sees the larger cross section of the galley at lift. The shrouding goes almost half way down the wheel. Even the other side has more shrouding around the wheel than yours.
The pictures of the lifter were not mine. I didn’t post pics of my lifters Hemi-itis did.
 
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