Variable hydraulic lifters for 440 engine

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WietseR/T

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Hey guys,

I am new around here, since i own a B-body i am mostly active on FBBO, but i have been looking here on this forum and have found plenty useful information around here.
Now i would like to raise a question some of you might be able to answer, or have experience regarding variable hydraulic lifters.

I own a '69 Coronet with a 440 engine and 727 auto tranny.
The engine has a Hughes Engines hydr. FT camshaft, HE3844BL, 238/244 @ .050" with .572"/.576" lift. (283/291* @ .008")
This cam is obviously not a street cam but this is how i bought the car.
While avoiding to change the whole engine setup i want to make it a bit more street friendly, and i was thinking variable hydraulic lifters could help me out.
I've come across the Hughes Engines variable lifters HUG 5003 and also read a lot of things about the Rhoads V-Pro street variable lifters.
Now at idle i have 5-6"Hg vacuum and obviously idle quality is not that great.
The engine has flat top pistons, 906 heads and compression is about 10.25 - 10.5 with a cranking pressure of about 160 psi.

Anyone here has any experience with variable hydraulic lifters? And does it help to reduce the lift and duration at idle to obtain a better idle quality and vacuum?

I did notice people mention they are noisy, my engine has around 50-60# oil pressure during driving and 40# is the lowest i've seen at idle.
Currently i am using 20W50 oil, and the Hughes Engine lifters state to not use any heavier oil than 10W30. (Rhoads does not mention any oil viscosity requirements for their lifter)
So if i had to swap to a different viscosity i will loose some pressure i think.
I am using a new HV Melling oil pump but wonder would a HP pump be a requirement?
The car is not used for racing/strip purposes, i want to use it as a hot street car

If you have any experience with these type lifters i would like to hear your experience with them if they help in improving idle quality.
 
I think something's wrong if you only have 5-6" vacuum at idle with that relatively small cam (238/[email protected]).
Either it is not degreed properly, or the idle ignition timing needs more advance (probably 18-20 degrees with that cam).

I run a [email protected], .652" on the street in a 451 with similar compression and it idles at 8" (although at 1200 rpm, and 27 degrees). What's your idle rpm and timing?
 
The cam is degreed properly, Installed centerline is at 105* as per specs. (108* LSA, 3* advance)
Initial timing is now at 14*, even with 18-20* initial i cannot get any higher vacuum then 7".
Idle rpm is around 725, i've had a hell of a time to setup the idle circuit.
I can set it the initial timing to 18*, but then i will have to nearly close the curb idle screw otherwise it runs 1000rpm.
This brings other problems, because i need to feed it with the mixture screws and it will run really rich during cruise. (i have an AEM AFR meter installed, showing 10-11 AFR during cruise)
I had other issues with this as well as the idle rpm dropped over 200 rpm when putting the tranny in gear.
There is still some improvements that can be made which is ongoing but the settings as they are now are very near of where i want it to be. (low idle and a 100rpm drop when going in gear and a more decent AFR going by the spark plugs)
But obviously the long duration of this cam is not helping me, therefore i wondered if these variable hydraulic lifters are any good in helping to tame a cam like this a bit in idle and low rpm.
 
What intake and what intake gaskets are you using.
 
The short answer is, yes, bleed-down lifters will work as a crutch, but are sensitive to oil weight & pressure, and noisy. I suspect most of the advice will be that you have too much cam for your converter's stall, and to change one or the other.

If you're cruising below 11:1 at highway speeds that also needs to be fixed unless you like changing plugs. (Light throttle low speed cruise is mostly if not entirely on the transition slots).
You're going to have a hard time keeping the rpm drop reasonable with a tight converter and that duration & LSA, but get the idle mixture, rpm and timing right first. Then start tuning the transition circuit, then the main, then the power valve.
 
The reason I ask about the intake is because I have had 3 with the same problem. Aluminum intake and just a steel valley pan, they never seal and you have a vacuum leak and it's always under the intake not on top. you have to use a paper gasket with a aluminum intake.
 
I agree. This is a rather mild cam. Have you double and triple checked the secondaries to make sure they are not opened slightly? That would allow you to pull more initial timing in and be able to idle it down.
 
TC stall speed is around 3000, i think it is a B&M but this engine was rebuild several years ago by a PO.
So i have not all details of it, it's 11" and darkblue....mystery TC, lol.

AFR on the gauge i am questioning more and more, because the plugs don't look that rich really.
For sure at idle it is talking BS due to cam overlap contamination.

Gaskets and valley pan are from Fel Pro, the valley pan was sealed with a coat of Permatex.
I did check the gap when test fitting the intake and there barely was any gap to be found.
I have tested for leaks by blocking off the crankcase breathers, with a gauge on the dip stick, but it builds up pressure from the blow-by so there is no vacuum leak.
A friend suggested to check the PCV valve, because likely this would be in WOT mode with the low manifold vacuum and allowing too much air in...which it did.
So for now i have disconnected and plugged the vacuum hose on the carb for the PCV, and waiting on an adjustable PCV from M/E Wagner to come in.
This was also the reason for it to drop so far in rpm when engaging the tranny, the mixture went very lean.
At that time i was keeping idle at 900 rpm, almost 2 turns on the mixture screws and it would barely stay running when engaging the transmission.

Transition slots are now roughly a little longer than wide, mixture screws are at 1 turn.
At 700 idle it goes to 600rpm in Drive, before i had this help i could not imagen it would run that low rpm.

DrCharles said:
but get the idle mixture, rpm and timing right first. Then start tuning the transition circuit, then the main, then the power valve.
Click to expand...
I am still working on this, i have the idle tuned in near enough.
When i receive the new PCV valve i want to set it up and install it, after that it might need more adjustment again so i rather wait for that.

RustyRatRod said:
I agree. This is a rather mild cam. Have you double and triple checked the secondaries to make sure they are not opened slightly? That would allow you to pull more initial timing in and be able to idle it down.
Click to expand...

Yes, the secondaries are fully closed.
That was my next plan to dial back the initial to 10-12*, then open the throttle a little more and close in the mixture screws. That should reduce the rich mixture.
Then again, i have kinda lost faith in the AFR meter as it is partially lying.
I have cleaned up the spark plugs and once the weather allows i will take it for a good drive and see what they tell me now.

But these variable lifters are not really for this setup then?
Yes i understand they are noisy, but if they do work that is what i have to accept while getting better idle and vacuum, right?

Just for the info, the carb is a Holley 770 Street avenger with vac. secondaries and electrical choke, jetting is still as it came from factory.
Edelbrock performer rpm dual plane intake, MSD RTR distributor, 1-7-8" headers.
 
Are you running a PCV valve? on more than one occasion, I have seen them have an internal vacuum leak. I would check that and EVERY other possible source for a vacuum leak.
 
oldkimmer said:
Like I said on B bodies. Rhoads lifters flat out work. Kim
Click to expand...

Yes, i did see your comments but i did not want to hyjack the thread.
Although most others seem very sceptical about them, but you are using them and with others seems more "hear and say".
How do you experience the noise caused by them, and what oil viscosity and pressure do you have?
And what cam are running them on?
 
RustyRatRod said:
Are you running a PCV valve? on more than one occasion, I have seen them have an internal vacuum leak. I would check that and EVERY other possible source for a vacuum leak.
Click to expand...

I was using a generic PCV valve, which due to the low vacuum is in WOT mode, allowing full flow instead of the reduced flow at high vacuum.
Therefore i have ordered the M/E Wagner adjustable PCV valve to set it up so i only allows a very small flow during idle.
 
I have run them from basically stock to mild to wild. I like them. Different weights of oils in different motors and up to 80 psi cruising. Krazy Kuda is a big fan of them also. But I agree that u should have more vacuum than u have. Kim
 
The first time i tested the vacuum on the car i could not get any higher vacuum than 7", after i had the intake and valley cover removed for an inspection/clean up and partial painting and reinstalled everything with new gaskets and never seen any better vacuum than 7" after that. (reinstallation of intake did not change, so it was not leaking before)
Now the engine was partially disassembled, cam degreed as it was not installed as it should by a PO, redid the complete valve train, installed B3 geometry kit to correct for the roller rockers, new correct length push rods and so on.
Now again, i am still stuck at 7" Hg when running 850-900 idle. So again, intake reinstalled with new gaskets and same story, so again the last time it did not have a vacuum leak.
Crankcase is building up pressure after a short time if i block it.
I am running 725 idle now with 5.5"Hg, if i want 10"Hg i need to run 1000 rpm idle.

The only thing remaining is the brake booster, i had tried this before but i will try again with disconnecting it.
Where else could be a vacuum leak?
Well, it could suck from the crankcase if the intake flange leaks, but it could also leak towards atmosphere right?
So it could suck direct from the air into 1 or more intake runners right?

Could i try with removing the carb, install a blind plate with a connection for an airline and "pressurize" the intake.
I know it depends on the engine position how many intake valves and exhaust valves are open but i guess i could get some overpressure on the intake and in the meantime spray some soap around the runners where they meet the cylinder head.
If i get a foam party i know it is leaking, which will give a vacuum leak when it is running.
 
I think 725 rpm at idle is way to slow 900 is more like it. If it is slamming into gear then the converter is to tight. The Rhoads lifters will help for sure. I didn’t mind the slight ticking at all. Kim
 
I can try and ramp up the idle to 900, just by turning the initial advance to 18*-ish.
First i will check again on the intake to see for leaks, after i can play around with some settings and see what it does.
If a am still not happy i will consider the variable lifters to install, so from what i read is that the Rhoads are the best right?
You can actually set them where you want as where the Huge Engines seem not adjustable in that way.
 
Last edited:
How do they work, then? (What changes with RPM to make the lifters longer or shorter?) Purely centrifugal force?
 
DrCharles said:
How do they work, then? (What changes with RPM to make the lifters longer or shorter?) Purely centrifugal force?
Click to expand...

From what i understand is that they work by fluid velocity that needs to go through an adjustable orifice.
The lifters leak off in a controlled manner, at low rpm the pressure that the pushrod applies to the lifter piston allows the oil to leak out until a certain extend.
When the rpms go up, the time the oil gets to flow out through the same orifice is getting shorter and the quantity of oil that remains inside is getting more, thus having the piston at a higher position as rpm increase. (this higher position of the piston is what gives the cam lift and duration back)
Since the Rhoads are adjustable, i think that when increasing/decreasing the lifter pre-load, you increase/decrease the amount of lift and duration that the lifter will remove from the cam motion.
 
The lifts mentioned by the OP for his cam are for 1.6 RR.

If that’s what he’s using, then it will make the motor “act” like the cam is about 5* more duration in the lowest rpms.

The Rhodes style lifters would effectively take that back out.

There is nothing being “adjusted” in the lifter to alter how much they bleed down with different rpm.
It’s just time.
As the rpm goes up there is simply less time to bleed the oil out.
 
he throttle a little more and close in the mixture screws
This has me confused. The mixture screws aren't supposed to be closed. They are adjusted to highest rpm/vacuum. Also, I wonder about the power valve. Have you checked what it's rated for?.
 
Hang on, this is a 440. I know pretty much nothing about BBs but I have noticed that the valley is divorced from the intake, so it seems to me that it would be impossible for the intake to evacuate the crankcase, as there is no physical connection between them.
But it is still possible for the intake to suck air on the underside of the ports. That's gonna be a tough test.
However, if you still have the previous gaskets, you might be able to see it in the compression-pattern.

The only other places I can think of for air infiltration, are;
in the EGR circuit, if your intake has one;
or a cracked heat crossover, if your intake has one.
 
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