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oville · 08-02-2015, 10:32 AM

Have AL headed 455 with comp hyd roller old faithful cam. Adjusted rockers with just over 1/2 turn past zero lash. Ran car for a bit up to operating temp and shut it off. Fired up 5 min later and taps loud like a bad lifter for 15sec then back to normal. Wondering if need to adjust on the rockers AFTER getting motor hot? Maybe AL heads expanding a hair is putting more clearance?
Already had to pull intake once to send back collapsed brand new lifter; and these are the new dash S type from comp.

oville · 08-02-2015, 10:34 AM

Cam was degreed and contact pattern of the roller on the valve tip face was in the middle third with Scorpion 1.65 ratio rockers

54nomore · 08-02-2015, 12:13 PM

It may be another bad lifter

Half a turn should preload the plunger approximately .025". I don't believe hot versus cold would be THAT much change. Typical solid lifter lash specs only differ a couple thousandths between hot and cold to compensate for thermal expansion.

oville · 08-02-2015, 01:43 PM

I do have another set of replacement lifters but swore if I had to pull the intake again was going to put Crower solid rlrs in there and do the hybrid route, hopefully don't come to that. Thought about cutting holes in some old valve covers and adjusting by ear with it running. May just get it hot and run the lash again going to 3/4 past zero

BierManVA · 08-02-2015, 05:55 PM

After doing a lot of research and talking with one of the best Pontiac guys in the country, I went with solid rollers. Actually a good choice to run on an HR cam. Set lash to around .006-.008 cold and let em rip. No collapsing rollers to worry about but you will need to check lash periodically. No biggy. Good for another few hundred RPM as well as you won't be as susceptible to valve bounce.

Consensus from my engine builder is that these retrofit hyd lifters just don't perform or last well.

Note: you may need to use restricted pushrods if you go this route.

Cliff R · 08-03-2015, 05:59 AM

Try running them at one full turn down from zero lash instead of half a turn. Some make noise when adjusted in that manner, and it may help quiet them down to the run the plungers deeper in the lifter bodies.....Cliff

oville · 08-03-2015, 07:26 AM

Does anybody know how many turns past zero lash will bottom out the lifter?

Cliff R · 08-03-2015, 07:43 AM

Good question, and there is not direct answer for it. There have been several changes made to the Morel HR lifters. I build a good many HR engines, and have noticed that the most recent version(s) are short travel.

I've always favored short travel designs and like to run the plungers deeper into the bodies and not leave so much oil under them. My luck with any type of hydraulic lifter has been poor over the years. I can't seem to get a set of 16 that doesn't have a "ticker" in the bunch someplace.

This prompted me to go to the HIPPO solid rollers and run the "hybrid" set up with my current engine. With the lash set at .005", it is the quietest Pontiac engine that has ever sat between the fenders of my Ventura, and the most powerful as well.

As good as the hybrid set-up works, I'd still like to run HR lifters on it, and may be going that route while it's out over the Winter. The only reason is that in that chassis it's just too big of a PITA to adjust them. The wiper motor has to be removed, PB booster is still in the way, and still it's nearly impossible to get to the back two on each side and do a good job setting them.

I'm considering going to th the latest HR lifters and tight lashing them at .010" to see if they will run like the solids and still provide zero lash, minimal noise, etc......Cliff

67GTO4SPEED · 08-03-2015, 07:53 AM

Not trying to hijack the thread, but when you do the hybrid the set-up, are you still able to run the Hyd roller springs and just change to the solid roller lifters or do you have to run higher spring pressure solid roller springs?

Cliff R · 08-03-2015, 08:07 AM

I didn't change the spring loads, as the cam profile is still a hydraulic roller grind, not the solid lifter profile.

What you are basically doing with a "hybrid" set-up, is taking the hydraulic action out of the equation, and running a true anti pump-up lifter.

The problem I've seen with doing this is that you MUST run really tight lash, or you loose a LOT of the cam profile.

Just changing from .008" to .005" will decrease vacuum at idle about 2", and the cam makes the engine a LOT lumpier at idle. This is telling us that you are loosing some of the cam profile with "loose" settings, so ideally, the closer you can run to zero lash without issues the better......Cliff

oville · 08-03-2015, 10:37 AM

I assume if switched to hippo would also need longer pushrods?

Also do there need to be oil restrictors tapped in the block? Heard restricted pushrods is not the right way to control oil flow. Motor now being together so....

Cliff R · 08-03-2015, 10:44 AM

No restrictors needed with HIPPO's, and yes, much longer pushrods required. I have a set of .080" for sale in the race parts for sale section that I ran with the OF cam and HIPPO's, they are 9.500's nearly as I can remember.....Cliff

Tim Corcoran · 08-03-2015, 12:23 PM

I am surprised that more people aren't running the Johnson Lifter hyd roller lifters. These are top quality lifters and are made in the USA. Seems everyone keeps buying comp cams Chinese stuff even though their service history is not so good. I'm thinking people get the comp stuff because of the price but in the long run aren't saving much.

Cliff R · 08-03-2015, 12:46 PM

All the ones we've used have been USA made, pretty sure Morel makes them.

Do you have part numbers and SOS for the Johnson retrofit Pontiac HR's?......Cliff

tom s · 08-03-2015, 01:35 PM

I know Morel makes Lunaties.Tom

oville · 08-03-2015, 01:40 PM

I thought comp hydraulic roller lifters were made in USA, is that not the case? Crower solid rollers are made here for sure right?

surfsama · 08-03-2015, 02:04 PM

Someone posted this list in an earlier discussion on this subject:

Comp Cams, part # 857-16 old part number. 857S-16 new part number.

Luhn Performance Part # ST2112OPR. Short Travel (Johnson Lifter)

Crane Part # 28532-16.

Crower Part # 66333-16 (Johnson Lifter)

Howard Part # 91466 (Morel Lifter)

Lunati Part # 72334-16 (Morel Lifter)

Morel Part # 5884.

Tim Corcoran · 03:51 PM

Johnson Lifter, Hyd Roller Lifters
Johnson Part #21120P Standard Travel
Johnson Part #21120PR Race
Johnson Part #ST21120PR Short Travel

I don't recommend using the standard travel as the leakdown rate is not controlled as well as the R's and the short travel lifters.

The new comp Cams 857S hyd roller lifters are made by Morel and are sold with a comp cams part number but they are the same as the Morel 5884. And the good news is the Morel's are made in the USA. Don't know who comp was getting the old 857's from but comp does not make their own lifters.

gtofreek · 08-04-2015, 07:58 PM

Aluminum heads expand and grow away from the pushrods. With solid lifters, it's about .007" on a Pontiac. You need to run more cold pre-load. Like 1 turn as Cliff mentioned.

Cliff R · 08-05-2015, 06:27 AM

+2

When I first went to the "hybrid" set-up, I lashed them at .008 intake/.010" exhaust, dead cold.

I checked them fully warmed up and heat soaked and they had opened up about .005" or so. I reduced the clearance to .005" intake and exhaust and they a have ran fine now with very minimal noise for many years

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