Solid rollers on a hydraulic roller cam
- Thread starter Carnut68
- Start date
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I have done it before and a friend is doing the same thing right now on a 512 using a XR292HR-10 with iron heads.
He contacted Comp Cams and they recommended .010-.012" hot lash using the XR292HR.
With the aluminum heads you should use a very tight cold lash, probably no more than .004". Because.....those heads will expand, lift the rocker shaft and cause the lash to loosen about .006".
He contacted Comp Cams and they recommended .010-.012" hot lash using the XR292HR.
With the aluminum heads you should use a very tight cold lash, probably no more than .004". Because.....those heads will expand, lift the rocker shaft and cause the lash to loosen about .006".
Carnut68
Well-Known Member
I was hoping you would chime in. That's good to know. Parts availability is going to start becoming an issue. I'd like to gather some things up now. Shortblock is done less camshaft.
I believe Engine Masters did an episode on this very subject with Dyno results.
512Stroker
We are all here because we are not all there.
I am getting ready to swap out Comp retro hyd rollers for a set of Morel solid rollers in my iron head 340. Comp XR274HR10
Cold lash @ .002 Hot lash @ .006
I have all the parts just waiting for the right time to tear it down
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I should mention that though Comp has recommended .010-.012" hot lash, I personally use .005-.006" hot lash. So with aluminum heads things get a little tight under cold conditions. That is when I just use a solid roller cam. My friends 512 will be able to use the really tight cold lash with the iron heads. Which is fortunate as the build will need the tighter lash to lengthen the cam out some.
MOPAROFFICIAL
Oogliboogli
Just don't end up with more than .016 HOT and you'll be fine.
Solids on a hyd roller is the longevity route imo. Liked. I'm into it.
Solids on a hyd roller is the longevity route imo. Liked. I'm into it.
Carnut68
Well-Known Member
It's not going to be an everyday driver or I wouldn't even consider solid lifters. I didn't put 25 street miles on the car this past summer. About 8 passes at the drag strip. I built this to get away from race gas.
MOPAROFFICIAL
Oogliboogli
I drove mine everyday.
mopardude318
Well-Known Member
I thought there was a thread floating around where someone was taking the insides out of a factory roller cam engine and making a solid piece to insert inside the lifter body.
Carnut68
Well-Known Member
I know I could go the custom grind route, but with parts availability how long of a wait? Just look at Summit and Jegs and other vendors most everything is out of stock. You can't get a Howards cam anywhere except for maybe a sb Chevy. I guess if I don't like it I could change it later. Get it together fire it up and see how it does. Anyway you look at it 511 ci in an A body w/391 gears and an 8in convertor should be a handful.
I have done this many times, & know others who have too. No problem if the lash is kept tight. 010-012 is too much at operating temp [ hot lash ]. Hyd cams have short lash ramps, & going too big on lash will put the lifter on the flank, which causes noise & valve train stress. Aim for 0.004-6" & you will be good.
512Stroker
We are all here because we are not all there.
.004-6
Hot or cold lash?
AustinGriggs
Well-Known Member
I did it on my 383, I set them at .006 Cold. I ran them like that, but will be doing them at .003 this next go around. The car gained RPM and runs good.
512Stroker
We are all here because we are not all there.
Iron or aluminum heads?
AustinGriggs
Well-Known Member
Iron
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