NVetro

Thanks Injuneer :-) We'll ill keep everyone posted, i'm getting a new tune and then taking her back to the dyno this weekend. If i still think she is alittle down on power and the peak rpm seems abit low, then maybe ill tryto readjust the rockers. Ill repost later this weekend.

SS RRR

Is it not possible to have it tuned while on the dyno?

SStrokerAce

Nick, just warm up the car and readjust the rockers. There IS power there and it's better to run them at zero lash than too tight.

Bret

SS RRR

Hydraulic lifters? Especially Comp R's? No chance in hell I'd do that. The sticky thread regarding Comp R's and their "failures" is enough evidence to avoid that like the plague.

NVetro

I agree a rocker adjustment mite be in my future. Gonna see what she does this weekend, there definitly mite be more power from the rocker adjustment. Lets see what she does :-) Thanks for all the replies.

SStrokerAce

Old Comp R's, yes I would do that. New ones wouldn't let them out of the package in the assembly room.

Bret

SS RRR

That's too bad. Especially since they've been run with great success. I'm using the new ones, have adjusted them numerous times and they have been faithful for me. The secret is knowing how to adjust them w/in their tolerance window. There's no way in HELL I'd ever expect and trust ANY hydraulic lifter to serve its purpose at zero lash. I see no reason for it. You get one that fluxuates in pressure ever so slightly and there goes a pushrod walking its doggie, banging out the clip and the rest is history... just like the pics provided in the sticky thread. There are are big cubed/big shot/hydrolic cammed 600 to 800+rwhp LS1 f-bodys using them with no problems. Just had one do a rear bumper cover scraping, license plate bending, smashing oil pan, headers and tranny case wheel stand last weekend (aka ATVRacer on other boards).

Jim D

Just a quick thought...The Caprice didn't have roller rockers, right? Maybe getting an LT4 knock sensor module will help get rid of your false knock readings.

Sweetred95ta

Confirm that it is indeed false knock and then zero out the knock retard tables. You need a tuner at the dyno with you to get the a/f correct. The timing is probably pretty close already. If you have tuning software, it's not that difficult to mess with the WOT a/f. I would get the idle and part throttle BLM's in order first, but that's just me. I don't understand why people spend the money and install a cam that large (for a HR) and try to get mail order tunes to zero in on the correct tune. Mail order tunes get it close and driveable, but after that, you need to find someone to do idle, part throttle, and WOT (dyno or street w/ a wideband) tuning. Back and forth with the mail order tunes is going to cost you money and take forever. Is the car surging? Running rich at idle and part throttle?

SStrokerAce

Well considering with a OEM lifter or something that doesn't break like a Morel you can run them for years at zero lash IF you do it properly it's not a issue.

The problem is that some of the Comp R's fail when you put them in their preload window, so it's not the lash settings that do this. NEVER HAS BEEN it's the clips are either bad or they are not, which my guess is a heat treatment AND design problem.

FWIW, stop beating this horse. YOU ARE THE ONLY GUY WHO HASN'T SEEN THIS FIRST HAND!!! THAT DOESN'T MEAN YOU ARE MAGIC!!!! JUST GOT A GOOD SET OF THE DAM THINGS.

Bret

SS RRR

LMAO... I'm not quite sure what you mean by me not seeing this "first hand.." but whatever, cheif. I've seen enough pictures and heard enough stories to know that most of it is crap. And beating a dead horse? Aren't you the one who suggested ZERO lash on Comp R's?
P.S. The LS1 I mentioned... there's a shop in my neck of the woods owned by a dear sweet friend of mine that only uses Comp R's in their big dollar setups. They have 4 f-bodys that are all currently running in the low 10 to mid 9 range. Are they lucky too?

Jon A

It's COMP who recommends running them at virtually zero lash (.004-.006 without specifying hot or cold). If yours break tomorrow, it's COMP who will tell you the reason they did was because you were running too much preload.

Really, you are the broken record on this issue. You really think people having success with every other type of lifter but have failures with these is due to their incompetence? Because they aren't going against COMP's specs when they set the things up? We're so stupid because we didn't ignore what COMP said? Did you ever think there might be a reason they say not to preload them so much? Just because it hasn't happened to you yet makes everybody else stupid?

Yeah, broken record is right.

SS RRR

Regardless the .004 to .006 is not zero lash and can mean the difference of the plunger smacking the clip and having ample clearance so that doesn't happen. In fact, depending on the thread count of a rocker stud it can be between 1/8 and 1/16 turn. I've adjusted mine both hot and cold. No I never said you or anyone else was "stupid". But did you take a good look at any of those photos in that thread? Did you not see where the clips got the snot hammered out of them from the pushrods walking off the lifter? And that's the lifter's fault how?
Tell me this... why is the clip falling off anyway? Does it just fall off? I'm still unclear as to how that can happen. Especially when every photo I've seen so far the clip is somehow damaged. No I am not calling anyone stupid. However I am not convinced that the failures I have seen are the lifter's fault. Not only that but the testimonies from those running them here in my area as well as a reputable shop in Maryland having nothing but success with them. Sorry you think I called you stupid. That's the furthest thing from my mind. I'm just very stubborn when it comes to such controversial subjects especially when the evidence presented, to me, is questionable. I'm not a bandwagon jumper. I read the sticky thread of woe and dispare before I bought mine. I didn't see the concern therefore I bought them anyway.
And yes.. I tend to be a broken record about these kinds of things.. especially when it keeps getting brought up.

Jon A

Yes, you might have noticed I actually took some of them.
When a guy had a valvespring break, yes. In other cases, such as mine, no. The pushrods never walked off the lifter in my case. The engine ran just fine without those clips, actually. The only problem is where the clips went, and trying to adjust the valves after a clip is already gone--sort of difficult to find zero lash after that.
Because the exact same use by the exact same people doesn't break stock lifters.
Why, how? I wish I could tell you exactly why and how in every case. Sometimes one needs to throw in the towel and accept the end results as the end results, especially when it's a problem that no longer needs a solution--they do. Yes, they get "somehow damaged." Then they fall off. End of story.

The thing is, you're missing the big picture here:

1) A hydraulic lifter that only has a safe operating range of .002" is fracking rediculous. Run less than .004" and most agree you'll fail the clips. Run more than .006" and Competition Cams, along with many who were running more than .006" and got the falure anyway (just not you, yet) say you will fail the clips--good luck getting warrantee replacements if they admit to following your advice. What about those who prefer to adjust the valves with the engine running? You can't do that without running zero lash for a minute or two. No other lifter will be damaged by this.

2) Why bother? Why on Earth would somebody want to run these things today? Because they're cheaper than dirt? No, they're damn expensive. Because they're the only lifter that can handle more spring than stock? No, that's no longer true. Because they're just way more durable and reliable than stock? Hell no.

With more and more people moving to Beehive springs, fewer need to replace their stock lifters at all. The stock lifters, and their replacements, are really quite reliable with moderate spring pressures. The rash of Comp R failures, if anything, has saved people with somewhat mild setups a bunch of money and given them better reliability.

If you want to run springs the stockers can't handle, we now have Morels. 1/2 turn of preload ought to make you happy. I simply don't see any reason to even fret over the hows and whys of Comp R failures any more because they aren't needed. At all. For anything.

SS RRR

Once again I must be lucky as all hell. I've ran them at zero lash whilst adjusting rockers. However you don't need to in order to adjust while running. You can always go through the routine of setting them one by one and then starting the engine. I see no harm in running a lifter at zero lash at idle. It's the WOT where lots of **** can go wrong!
I understand your point and got these when I thought they were needed.
Agreed... but only to a certain extent.
YES SIR, SIR!
Did you not read the part where it was suggested to run the lifters at zero lash? Please re-read my original post before crowing on that I am the one who started this nonsense.
Basically for all the other crap that I didnt' specifically respond to and "like a broken record", I am still not convinced ALL those lifter failures are the fault of Comp. Yes perhaps they have less tolerance than a different lifter when someone wants to run zero lash on a lifter and the c-clip can't handle being smacked around or maybe someone doesn't take into account how many turns is .006-.008 for their setup or some people just plain don't know how to adjust valves. WAY TOO MANY VARIABLES to specifically blame Comp Cams. Hell you don't even have any hard evidence as to how yours failed yet you are just going to follow the blind and blame the lifter. It'd be very interesting to see the success-to-failure ratio with this lifter.
The "doom and gloom" thoughts are much appreciated regarding my lifters, but since they've been in use for approx 7K miles I don't think I'll buy into the bandwagon jumping quite yet...