How much lift with stock magnum roller lifters?
- Thread starter Drifterhp
- Start date
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Currently running .580 (theoretical) before losses due to geometry, in my 89 LA roller cam block. These use same lifters as Magnum, if memory serves me correctly, they are manufactured by Melling. I did install new lifters when building engine. I have had zero issues with this setup to 6400 RPM.
I've came across these and confirmed they'll work in Magnum of hydraulic roller cam LA blocks. I am planning on trying a set of the fast bleed downs in a 360 LA block.3.9/5.2/5.9 ENGINE - Lifters - HiPoTek
DrEamer
I suffer from cars on the brain!
Those are made by Johnson hylift. I bought a set direct from them, but got the Direct Shot upgrade. I'm not sure how inventory is now, but it was getting low when I ordered months ago. The nice thing about getting them direct is you save a little money in the process.
pishta
I know I'm right....
$70 more for "slow leakdown".. What's the draw on those?
I don't see where they would be limited as far lift. Spring pressure, maybe. I "guess" if you had either so much lift OR such a reduced base circle they got out of their oil groove, then yeah. But sheer physical limitations regarding the plunger's abilities, naw.
360duster
Well-Known Member
I used these stock HR lifters with .387" Lobe Lift without trouble. As far as getting uncovered see the pic, this is with another cam @.373" Lobe Lift - absolutely no problem, could go much further with my block (90´s LA Roller Cam Block).
Michael
Michael
I wonder if you could take the springs and plungers and discs out and use them as solids? Certainly somebody's tried it. I would.
motorpirate
serial mopar owner
I have been wondering that too.
How exactly would you do that?
Make a spacer to "fill the void"??
I didn't mean the plunger too. That would have to stay. It can be defeated though. I've done it on flat tappets and it worked well.
Here's a video showing the conversion of an LT1 Chevy lifter. I'm certain the Magnum Mopars are very similar. It appears all he's doing is removing the spring and disc and flipping the plunger over and reinstalling.
Course he says it's just for checking piston to valve clearance, but I guarantee you somebody's run um on a solid roller cam somewhere.
I’ve seen that particular video, and read on another forum (think it was a Dart /Duster forum) of a guy who was making inserts to take up the void, which left some amount of clearance after reassembled, they weren’t entirely solid just some built in lash I think. Made the pieces for a few people and that was it. Guys that have roller blocks sure could use something like that to retain the factory spider and dog bones and save a heap of cash
360duster
Well-Known Member
i´d fear that these new "internals" would not be able to withstand the constant hammering when there´s some play inside.....and fail with catastrophic engine damage. If there is a way to do it safely, then this would be a nice option i´d propably go!
Michael
Michael
It was on this forum where someone made inserts: Magnum solid roller style lifters... was quite a few years ago so the idea is nothing new.
Yeah, that's where I had seen it too. I thought somehow they got all the slop out. I guess not.
With the Magnum blocks being more plentiful than the LA, and the factory roller components that are proven you’d think there’d be solid lifters already available from someplace for an easy drop-in conversion.
Yes you can, a fellow I know has done it. In fact I have a few set up that way in my garage. The internal parts combo came out of disassembled 350 chevy lifters. He has 5 seasons on his Dart using the converted lifters, he run his stuff hard and has had no issues.
Was he able to get all the slop out? It really wouldn't matter I wouldn't think as long as you included said slop when you adjusted the valves. Just make sure you were pressing down on the pushrod side to take the slop out.
On mine stock valve train 360 mag factory roller I have .512 lift and .020 retainer to valve guide clearance
Hughes has a set designed for more clearance how much I don’t know
Hughes has a set designed for more clearance how much I don’t know
DrEamer
I suffer from cars on the brain!
From the Johnson Htlift site
“S” or Slow Design: These parts have an “S” designation after their part number. So a Slow Design part number will look like A-0817S. These Lifters have a Leak Down on the upper end of the scale from 90 to 120 seconds. In a performance application these lifter will actually act like a mechanical lifter with very little effective loss of valve lift or duration at any RPM. Just like the “R” Lifters these have a much smaller Leak Down range that will also balance all of the cylinders to each other. These lifters are very hard to produce because the TOTAL clearance between the I.D. of the Body and the Piston assembly is reduced to less than 0.000120”, or 1/30 of a human hair. These are like super heavy duty shocks and can handle higher spring pressures without collapsing like the standard and “R” lifters. The only draw back of this type of lifter is that if the valve train should “Float” because of reaching a higher RPM than the valve springs can handle these lifters will try to take up the excessive clearance causing the valve to hang open resulting in a loss of power. Because these are Hydraulic lifters there is no lash or additional adjustment needed and the full cam profile is translated to the valves. In testing, not only did these lifters result in more power and higher RPM reading over other Hydraulic lifters they also reduced valve train wear and failure compared to mechanical lifters.
Alrighty. So then the way I read that, the valve lash is adjusted to zero. PERIOD. Is that correct? I think I'd wanna add maybe .002" lash.
Cuda416
Well-Known Member
Stupid question, be gentle...
What the aversion to hydraulic versus solid? Under pressure, the oil is damn near solid and doesn't compress right? I mean, I know it bleeds down but that fast?
I guess I think of it like the experiement kids do with corn starch and water. Add just enough water to a bowl of corn starch to saturate it, then poke your finger in. Goes right down to the bottom. now punch it, and it stops your hand acting like a "solid". In my head it seams similar in that the harder and faster you "hit" the oil, it's going to resist because of the viscosity?
BTW, with all of the talk I see about people wanting solid over hyd, I know I'm 100% wrong, but why?
What the aversion to hydraulic versus solid? Under pressure, the oil is damn near solid and doesn't compress right? I mean, I know it bleeds down but that fast?
I guess I think of it like the experiement kids do with corn starch and water. Add just enough water to a bowl of corn starch to saturate it, then poke your finger in. Goes right down to the bottom. now punch it, and it stops your hand acting like a "solid". In my head it seams similar in that the harder and faster you "hit" the oil, it's going to resist because of the viscosity?
BTW, with all of the talk I see about people wanting solid over hyd, I know I'm 100% wrong, but why?
As I recall, he had the perfect combination of internal pieces, using disassembled chevy hydraulic lifters, to take up the cavity space completely to the retainer ring. The end result was essentially no slop. When I get home tonight I will go have a look for the one he assembled to show me the process. The combination of parts went together like Lego! Lol
That's pretty funny. Was he using the crappy wire retainer or a snap ring?
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