hydraulic to solid FT lifter conversion

[BigBlockMopar]

Short of just getting a fresh set of lifters from Summit and having to do another camshaft break-in procedure, what would be your/the preferred way of converting a set of hydraulic flat tappet lifters into solids?

[Steve.k]

Buy a set of solid lifters, set at .004-.006 call it a day. Just did exactly that with Cleveland.Double check pushrod length.If your racing engine ask cam mfg about lash. Ours was comp and i called them.

[ProPower engines]

Why not just lash the Hyd. lifters??
It will give the same affect when the engine is running and the lifters are pumped solid. I do that for some solid profile cams in spec class stuff that must use a Hyd. lifter and no issues as long as there is a quality snap ring holding the guts in the lifter body together. The U shaped wire clips come out some times

[Geoff2]

Hyd lifters are only pumped 'solid ' as long as the oil doesn't become aerated.....
If you want to avoid that possibility, then a true solid lifter is the answer.
I have converted quite a few hyd lifters to solids, easy to do. I remove & discard the internal spring & valve assy under the piston. I use a s/steel spacer to replace the spring; along the length of the piston, grind a groove or flat [ like a Rhoads lifter ] so that there is no way for oil to pressurise the piston.

[cjperformance]

Why not just lash the Hyd. lifters??
It will give the same affect when the engine is running and the lifters are pumped solid. I do that for some solid profile cams in spec class stuff that must use a Hyd. lifter and no issues as long as there is a quality snap ring holding the guts in the lifter body together. The U shaped wire clips come out some times

Because hyd lifters never reflect lobe lift at rpm near peak unless you allow them to via 'only just' spring control which does not allow much over rev/accident allowance.
With enough spring and rpm limiter you can run way tight PV clearance or coil clearance with a hydro lifter, way tighter than is ok with a solid lifter, why, beacause of bleed off, you just dont get the lift that the lobe can provide. But yes, lash a hydro lifter a little and you do get better results. Bottom + min lash a hydro lifter and you get better results.

[cjperformance]

Hyd lifters are only pumped 'solid ' as long as the oil doesn't become aerated.....
If you want to avoid that possibility, then a true solid lifter is the answer.
I have converted quite a few hyd lifters to solids, easy to do. I remove & discard the internal spring & valve assy under the piston. I use a s/steel spacer to replace the spring; along the length of the piston, grind a groove or flat [ like a Rhoads lifter ] so that there is no way for oil to pressurise the piston.

Why not simply shim the piston below and above, give it .015/.030" movement, lash at .006/.010" and thus keep the correct oil metering of the factory valving?

[Steve.k]

Last set of solids i bought were around 200 bucks.Why even fool around for that price?

[BradH]

A BB Mopar will require different length pushrods, and you'll need to know what size tip(s) the solid lifter is designed to use (5/16" and/or 3/8").

I'd expect setting the lash when using solid lifters on a hydraulic lobe is critical, since a true hydraulic lobe won't have a lash ramp (proper terminology?). And you'll need to reset the lash hot from whatever the cold setting is to account for changes due to engine temperature. Or, maybe you know this already...

[BigBlockMopar]

I've put solids on a hydraulic cam before and the lash needs indeed to be set tight like mentioned and CompCams advised as well.
Worked quite well at the time.

Dropping in new solid lifters is not in the works currently. Don't want to go down that path right now.
*If* a change is considered then it will be an upgrade to a roller cam.
(Also I can't quite get the costs difference between a (cheap) complex/multipart hydraulic lifter and the simple (but double priced) one piece solids.)
So converting the lifters to solids is what's currently being considered.

What about running aluminium fillers/spacers under the lifter cups, instead of steel? Will this hold up?

[cjperformance]

I've put solids on a hydraulic cam before and the lash needs indeed to be set tight like mentioned and CompCams advised as well.
Worked quite well at the time.

Dropping in new solid lifters is not in the works currently. Don't want to go down that path right now.
*If* a change is considered then it will be an upgrade to a roller cam.
(Also I can't quite get the costs difference between a (cheap) complex/multipart hydraulic lifter and the simple (but double priced) one piece solids.)
So converting the lifters to solids is what's currently being considered.

What about running aluminium fillers/spacers under the lifter cups, instead of steel? Will this hold up?

NO , but mild steel works absolutly fine.

[blown265]

I once bought an expensive set of solid flat tappet lifters from a local cam grinder to use with a new solid cam.
After a few hundred miles, the rocker clearance on one started opening up. Reset it, but it opened again. "DAMN, I hope it hasn't lost a lobe" I thought. Pulled the lifter to check, and the base looked fine (!?!). Checked the roller rocker/pushrod/etc- everthing looked normal. I resigned myself to pull the engine again to see the cam (I6)
While doing so, and removing the remaining followers, we noticed that the pushrod cup of the offending lifter was sitting lower in the body of the lifter than the others. Disassembled it and found a badly converted 'solid' . The components inside the body had begun to wear/breakdown due to the poorly thought-out conversion method.
The cam manufacturer replaced it and the rest of the set immediately, but claimed no knowledge, stating they bought them from another vendor.
Another ' learning' in the books.

[Geoff2]

CJ,
A couple of comments:

[1] No, mild steel does not work fine. There is lash in the system. That means hammering of parts. So a hard steel is reqd to stop mushrooming. Which is why I use spacers out of s/steel. Hardened steel would also be ok.

[2] Why not use shims above & below the piston? Well you wouldn't use them above the piston because they would have to fit between the piston top & p'rod cup. This could also upset oil metering to the rocker gear, depending on the type of metering valve used in the lifter.

[3] Using shims stacked to the reqd height to get the piston at the reqd height so that the piston just kisses the circlip adds considerable weight; compared to a small spacer about 1/16" wall thickness that locates over the protrusion on the base of the lifter piston.

[4] Using the spacer I have described has no effect/change on the lifters ability to supply oil to the valve gear, because the modification does not affect the lifter's oil metering.

[tuffxf]

Gday
Also bought a set of solids around 2005 - 2006 approx from a local australian well known distributor
Same deal, converted hydraulics had a steel spacer but they werent hard and the small area on the od just got hammered , noticed it in the lash.
I did keep one for years, not sure whether i still have one.
Cheers

[blown265]

Yep, same time frame, though the set I purchased were from a smaller cam company who I'd bought from prior, and have continued to buy from since. Their design/engineering is good, and their remedial action was fast, so I gave them the benefit of the doubt.
(being the dodgy items were supplied by an outside vendor, that they initially werent aware of)

Regards
Paul