comp cams roller lifters vs ls7's
 

Which do you think is better? I ordered a set of the comp cams through Texas Speed. 200 dollars. Are they a decent upgrade over the stockers? Jump in texas speed, please.

i run the comp 850 lifters and run the car to 6500 sometimes and no problems. my ls7's just were too loud so switched over to comps.

these are the 875 comp "R"

What will the LS7's hold up to 7K?

I have had my LS7's to 7400 twice (that I know of). Both times by mistake, lost grip and tires broke free and my RPM's shot up on me. I had my rev limiter on my MSD 6012 box set to 7400, I just lowered it to 6800 to be safe. But no adverse affects (knock on wood!!).

If you have the right set up you can spin the stock lifters to 7200. I thought always that the upgraded lifters where the way to go but believe me when I tell you that the Valve train in the LS series engines are bullet proof.

Lingenfelter uses stock lifters

C6Rs use stock lifters

Katech uses stock lifters



Let me know if you need any more references.

The lifters will outlast anything else on the LS engine, and in my personal experience with LSx engines I have NEVER seen a lifter cause a failure, or be at fault for a failure unless something such as a bad/broken rocker, pushrod or other component caused the failure.


As far as changing them, the only reason I recommend going to Comp OE lifters is because they are cheaper then factory GM lifters, and the only reason to change is preventative maintenance... much like changing an oil pump or a timing chain at higher mileage, its cheap insurance and will be exposed anyway, so I change them. At -50,000 miles I mention it but dont recommend it, at 50,000-100,000 miles I recommend it, and at 100,000+ should be a requirement.

Now you hear all this BS about valve float at 6500 rpms on stock lifters. Valve float means you need to spend more money on valvesprings. My mech has pounded this into peoples heads time and time again, those who listened didnt have the problem, those who dont spend their lives looking for answers on why their car just never runs right.
Comp 921 springs - God invented these, they dont break, they dont fatigue, they last forever, they dont float regardless of valve size or weight or lifter, and EVERY combo my mechanic has done with them is still pulling flat at 7,000 with large aggressive cams. He has run them in every LSx he's had and every combo he has installed with his cams EXCEPT the first 10 or so, which he used PRC Gold springs, and after 90% of those had broken springs or severe float issues after 5-10K miles, he swapped them all out to 921s and stopped selling PRC/Patriot/AFR/TSP springs.

The only thing he has seen make those springs float is aftermarket rockers. There is absolutely no reason to run them on these engines and all except for the $1800 Jesel rockers have heavier tips at the valve which induce float at higher RPMs.

comp makes the ls7 lifter

the thing about the r lifter is there is a bigger ring around them to keep them in the bore on very high lift cams

I disagree about the valve train being bulletproof as I have had to rocker arm failures(needle bearings came out) and a lifter failure. Road pirate 1 has had ls7 lifter failures with no oiling issues and he runs 9's with an lsx 454. He recommended the morrell(sp)lunati(600 dollars) as they are good to 8,000 rpm. I've gone 383 all forged ms3 cam with 4500 stall turbo 350, 750 holley vic jr. intale and msdls box. Dual valve springs and hardened pushrods. With the harland sharp upgrade the stock rockers are a good deal. light and strong.

Comp 850s are fine..875s are good too but you have to set them up right

please expand

875's require adjustable valve train due to their very low preload requirements, if I recalll they need between 0 and .002 preload? Anyway very little and it is near impossible to attain this low preload without an adj. VT.

neither is a true hi performance lifter, stay with the LS7 to save money.
OR step up to a Morel