Comp cams evolution
 

So I see they have replaceable cartridges.My question is, Why would I ever need to replace the cartridge?

It's my understanding that the replaceable cartridge is more about modularity between parts and being able to provide a higher quality lifter, with better tolerances at scale over many different skus.

With the central cartridge being the "functional" part of the hydraulic lifter, they can build for more platforms with less tooling, in a more precise fashion.

As far as when or why you would need to replace the cartridge, if you had a lifter that had a poor bleed down rate, you could replace the cartridge instead of the entire lifter. Or, if you had a bearing failure, you could replace the cartridges and possibly clean the body/roller. I agree primarily the replaceable nature isn't a huge selling point. I think that's more of a them thing that helps keep quality up and costs down.

When I bought my first set I ordered 2 Xta cartridges,after like 3 sets now they are still in my cabinet.FWIW,Tom

My first set of evolutions had 2 that were noisy, they bled down after sitting a few minutes and clanked pretty bad on start up until oil pressure took over. From there they all seemed to have the typical sew machine noise which isn't a big deal but I know that bothers quite a few in this forum. I ended up doing 2 things.
Replaced 2 cartridges on the 2 clanky lifters. Ran it that way for a while. Then ended up going one full turn on preload from my previous 1/2 turn. They were happier at a full turn. Still a sew machine noise after things get up to temp and the oil thins out.

A full turn of preload is eating up a good amount of what you have for total plunger travel.

How is your geometry looking now?

Nice to have spare cartridges, to tune the valvetrain to quiet.

Yet, since the Lifter body wears out before the internal " Cartridge", the idea is just great on paper.

My engine guy said it took 3/4 turn to get a .063 preload on the evolutions . Actually heading over today to pick it up. It was noisy in the dyno room so I couldn’t tell if the lifters were noisy. I bought 4 extra cartridges just in case.

I have 857Ss in the motor I just dynoed and it was so noisy in the dyno room I could not tell if they ticked.

Yeah depends on your rocker stud thread count and to some degree rocker ratio. Im running 7/16-20 on this particular setup. A full turn is roughly only .050

Pretty much the same. 1/2 turn only added .025" of preload for a total of around .050

Depending on which Instructions you read these are supposed to have about .125" of plunger travel and they want them set in or near the middle. Im not there yet.

I wasn't even aware comp was still making the "S" lifter. I thought those went away a few years ago.

Im running a set of those in Dad's engine I installed about 6-7 years ago. I set them at half turn, .025" preload and they are nice and quiet. Theyve been an excellent lifter.

Motor was assembled a few years ago.