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Any one ever ran hydraulic lifters on a solid flat tappet cam?

Cranky

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I did a little bit of research on it and it looks like there are some people who have done it.... I'm not planning on doing it but a guy bought a 590 lift cam from me today and did not want to buy the lifters that I had and said he's thinking about running hydraulics.
 
That's dumb.
Solids on a hydraulic cam... maybe??
Hydraulic lifters on a .590 ... lol.
 
The only reason the lifters are "solid" is because the ramp is deemed too harsh for a hydraulic lifter. And generally they have more lift requiring more spring pressure which might overpower the hydraulic lifter. Otherwise, the cams are made of the same material and the "taper" on the lobe is there to ensure the lifters spin. Would I do it ... NO! But hey, you have the guy's money, let him knock himself out !!
 
Would I do it ... NO! But hey, you have the guy's money, let him knock himself out !!
So.... if I'm hearing everyone correctly, they are likely to beat themselves apart??
 
To be clear, Engine Master's test was with solid lifters on a hydraulic (roller I believe) cam. Solids on a hydraulic has been done for ages, but not the other way around....think about it...on a cam (solid) that needs some lash on the lobes, it's not going to get it with hydraulics that require preload..so wouldn't it be like running 0" lash which would also change the seat timing considerably?
I'm sure it's been done like the many other wrongities that guys do, and could probably be made to work...but why? Tell that guy holy hell man just buy the right lifters....Mopar guys I swear!
Just my thoughts, maybe I'm out in left field again...
 
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think about it...on a cam (solid) that needs some lash on the lobes,
The cam doesn't need the lash, the solid lifters do - as do solid rollers. Hypothetically if its a MILD solid lifter cam it would probably work just fine with hydraulic lifters.
 
I've done it and seen it done a lot on the dirt track circuit where hydraulic lifter rules are in place. We never had issues. I don't know how they would do in a low rpm street car.
 
Nothing to do with the lifters getting 'beat up'.

There is no mechanical reason to prevent hyd lifters being used on a sol cam, roller or FT.
But the idle will be much rougher than if sol lifters were used. The sol lifter cam lobe has much longer ramps so that lash is taken up gradually, so as not to 'shock' the valve train. The hyd lifter has the in-built hyd cushion/shock absorber, doesn't need the long, gradual ramps.


Bottom line: hyd lifters on sol cam will have a lot of duration at idle, giving a rougher idle & low idle vacuum.
 
A guy I know that once lived in this:

IMG_4486.JPG



Then this:

IMG_4487.JPG



Tried hydraulic lifters on a solid cam and wiped it out with less than a thousand miles. He bought a bunch of random parts to build a stroked 340. Over 15 year of ownership, he went through the engine numerous times because he just wasn't smart about it.

He assembled the engine without having it balanced and it shook like a paint shaker.
He blew head gaskets. He wiped out 2 cams. He lost a carburetor/air cleaner stud down the intake and split a cylinder wall.
He bought a used Gear Vendors unit and installed it without checking the oil level. On a road trip, it howled and quit working. He had to have that rebuilt too.
He installed wheel bearings and "torqued" them to 70 ft/lbs. On another road trip the steering got sloppy and he had to be towed home yet again.

He sold the car to buy property, in "partnership" with a married couple....he never added his name to the deed of the property and is now at risk of having nothing since there was never a legal document to his stake in the property.....

1 return (2).jpeg
 
To be clear, Engine Master's test was with solid lifters on a hydraulic (roller I believe) cam. Solids on a hydraulic has been done for ages, but not the other way around....think about it...on a cam (solid) that needs some lash on the lobes, it's not going to get it with hydraulics that require preload..so wouldn't it be like running 0" lash which would also change the seat timing considerably?
I'm sure it's been done like the many other wrongities that guys do, and could probably be made to work...but why? Tell that guy holy hell man just buy the right lifters....Mopar guys I swear!
Just my thoughts, maybe I'm out in left field again...
"Mopar guys",.......? You nailed it!
 
There is no mechanical reason to prevent hyd lifters being used on a sol cam, roller or FT.
But the idle will be much rougher than if sol lifters were used. The sol lifter cam lobe has much longer ramps so that lash is taken up gradually, so as not to 'shock' the valve train. The hyd lifter has the in-built hyd cushion/shock absorber, doesn't need the long, gradual ramps.


Bottom line: hyd lifters on sol cam will have a lot of duration at idle, giving a rougher idle & low idle vacuum.
If I understand what you are saying, running hyd roller lifters will work on a say on old MP Hemi grind cam that was designed for hyd non roller lifters?
 
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