Is there are set criteria for determining when Comp R lifters are recommended over the Comp regular OEM replacements? I've seen posts regarding radical cam profiles and NASCAR level spring pressures with recommendations for Comp Rs over oem replacements. However, I haven't seen anything indicating any criteria to go by in making a decision.

BTW, is there any downside to installing Com Rs in a moderate mod street car other than price.

I have got my top end apart right now on another matter and thought I might replace my low mileage Comp OEM replacements with Comp Rs if I would be better off. As in my sig I have the Com 218/224 with spring pressure at about 140# closed and about 360# open.

I would appreciate any recommendations with reasons. Thanks.

BTW, I did a search and could find discussions around my question but not directly to it.

 

with that pressure i would stick wiht the oem's, main reason people go to the comp r's is for over 400 lbs, and really the only downside to the r's is that the lash seems to be tricky to set (granted i have never owned them) seems that most people have most luck between 0 lash and 1/8 turn past 0 lash. i have schubeck lifters and i set my lash at .010 cold

 

I don't agree with you.. I think with a 140lbs pressure spring he should go with R lifters.. (Also a hydra rev kit will work very well) OEM lifters can't handle such that pressure (my opinion).

 

At a certain point spring pressures will collapse "stock" lifters. Lloyd is giving me a custom grind thats a little like the GM847 with a little more lift
and it will require Comp R's along with Hi-tech pushrods.I'll also be using bee-hive springs with titanium retainers.
Comp r's shouldn't hurt you at all. Just don't run them too tight. 1/16 of a turn past zero, max. At least thats approx. based on a 7/16 stud for my 1.6 rr's. Most likely thats how I will set them and then pull the covers and do it one at a time with the engine running.

 

With that spring pressure I'd run the Comp R's also.

I'm running 150# on the seat and 360# open @ .600. I ran a set of 78k mile stockers for a short time, and they held up fine. HOWEVER, I DID NOT put them through a 6500+ run or dyno pull. Their lives probably would have been short lived.

 

id rather just run the valves every 3K then **** with having the possibilty of collapsing HR lifters because of too much spring pressure from these fast ramp HR cams. id just run a solid roller rather then mess with hydra-rev kits and **** that just eat power.