I've got an older style lifter apart, but cant seem to get it back together to the same exact size that it was, in solid form. I stuffed a couple nuts inside, but cant get the retaining pin back in. I guess i could put the nut on a belt sander to fit...

Is there a "how to" somewhere?


Sbf lifters, you just flip the plunger over and reassemble. Is there an easy way, like this?

I want to run my ptv test with my lunati double springs and 7.4 pushrods in place.

 

Also, Ive heard there is a difference in preload between the old style (my soon to be mock up solid lifter) and the new style "ls7" lifter. I will be using the new style ls7 in this motor.

Will this ruin my ptv test results?

 

I wouldn't mess with a solid lifter, just get some checker springs on your head and use an un-modified lifter.

Either way, you need to use an adjustable length pushrod for PTV checking. Otherwise you'll never get to zero lash.

 

I would use a checking spring, but:

https://ls1tech.com/forums/17004914-post22.html

 

^^ What Rezin said

Make your lifter solid, use checker springs, and use your pushrod checker adjusted to zero lash. Doesn't matter what your lifter cup height is, what your preload is, or what your pushrod length is in this case. All that matters is that their combined height more or less rigidly connects your camshaft to your rocker tip with 0 play.

Here's what I did for solid lifters though, I'd call the cup at the top of travel as I was just able to get the snap ring in.

-(2) M4 standard thickness washers
-(1) M6 screw, ~12mm long.
-optional: (1) snap ring for retaining it all. Mcmaster PN# 99142A370. The original wire retainers shot across the garage never to be seen again when I was taking it apart so I needed a replacement.

 

If you have a shop nearby clean the lifter off completely and do a couple very small tac welds to hold the cup up. I did this to two of my old LS1 lifters that were replaced by some Johnsons.

 

Are you saying that the combined height of lifter and pushrod just make up the geometry to properly drive the rocker, and have no bearing on the valves traveling distance (as long as there is no slack present)?

If so, this will put my mind at rest, as I've been wondering how everyone gets the perfect mock up measurements of pushrod/preload/lifter while checking ptv.

 

Yes. you need an adjustable length pushrod.

you don't actually need a solid lifter when using checker springs. The checker spring is much weaker than the lifter spring

 

Here is how i mocked it up.

I dont have light springs so i used some foam from my pool noodle. My ls7 lifters are much stronger than the foam, so the plunger does not collapse.

I used an adjustable pushrod to subtract the .060 preload from the over all 7.4 length, and set it at 7.34. Rocker hit 22# within the first 3/4 turn.

After one full rotation i moved the adj pushrod over to the exhaust and did another 360.

I probably should have posted some cam specs before i went through this, but i have tons of clearance.

.176 intake and .143 exhaust.

Cam specs are 215/223 .609/.592. 112 +3

Sound about right? Is this excessive? Should I considering milling the heads to get a free bump in compression?


uploading images

 

That is a very mild cam by todays standards. PTV won't be an issue. You can mill if you want.

 

nice pics! Looks like you got it figured out.

There is no such thing as "excessive" PTV clearance. If you have the envelope available for more compression, then go for it, and re-measure PTV afterwards.

 

Yea, the cam was custom ground for a truck application, spec'd for DD fuel economy and a little fun.

Is it safe to measure this way?

.167 - .030 = .137
.143 - .030 = .113

What kind of compression bump will .030 net?

Thanks for your help guys. This site has been my number one source for everything ls related. I'd say 90% of the info ive found has been here.