[MeanGreen1LE]

Starting to buy parts and narrow down what I’m looking for to do h/c/i.

I have a set of mast black label heads on the way soon and I’ll be looking for less than max effort na but still aggressive when choosing cam. (I may make another thread for suggestions on that soon)

I want good valve train reliability so I’m pretty sure I want to go with Johnson 2110 drop ins for lifters with tsp roller rockers.

Since I’ll have aftermarket heads and new lifters what’s the best way to go about checking pv clearance.

I’ve read many articles and many to most say not to use hydraulic lifters. They state to use solid. I’ve seen methods to modify ls7 Type lifters to make a solid roller for this purpose but that doesn’t seem to help unless I find the correct pushrod length for this and then buy two pushrods to check. But that seems like a lot of extra work and would it even be accurate enough.

However: I have seen one that states you could use hydraulic lifter if you’re using check springs. I’m really hoping this will work because it will allow me to set one head up and find proper PR length and then put them on the other side with check springs to check pv. Not sure if I would use clay or dial indicator method. Clay is easier but may risk compressing lifters.

Anyhow just looking for input/guidance or if someone has maybe even done it.
Thanks.

[Tim M]

Great question...I've seen references where the factory pistons are limited in valve reliefs.

[NickeyMatt1LE]

I just use an ls7 lifter with the spring removed. Then use an adjustable length pushrod. Cam on the base circle, screw the pushrod out to zero lash, and crank the engine over by hand with clay on the piston.

[wwiiavfan]

Have you ever seen the Engine Power series of shows (now on Amazon Prime)?
They show the right way to check pv on a number of different episodes. Checking spring and dial indicator are the way to go. It’s been a while but I seem to remember them checking clearances as small as .050”. Only difference for you would be lifter selection and it seems like NickeyMatte1LE has your answer for that.

[MeanGreen1LE]

Originally Posted by NickeyMatt1LE

I just use an ls7 lifter with the spring removed. Then use an adjustable length pushrod. Cam on the base circle, screw the pushrod out to zero lash, and crank the engine over by hand with clay on the piston.

Thanks I’m probably just over complicating things and will go this route. It makes sense that if you get to zero lash with adj pushrod then lifter length being different should not matter. If anything having solid lifter for checking would be worse case scenario with “cushion” effect of hyd lifter.

What’s everyone’s thoughts on safe tolerance on these engines? .080 intake and .100 exhaust is the most prevalent I’ve seen at least for street engines.

[Tim M]

Good info!