Ok, so I put a cam in my LS2 over the weekend; the install was fairly straight forward due to all the information I was able to collect from this forum, the factory service manual, and a few other Internet sites ahead of time.

When my next door neighbor, who has been working on cars his whole life (but never an LSx engine), heard about the project he was pretty excited about it and wanted to help out. I figured what the heck, I could use all the help I can get right? He also suggested that we work on it in his garage since he had all the tools we might need and had a little more space. I won't get into all the details, because they really do not matter at this point, but needless to say we didn't always see eye-to-eye on the project but my car was torn apart in his garage.

Anyway, to the point of my post. We installed the Vinci Ultra Torque cam (yeah I know, it's a baby) and a set of Crane Gold 1.8 roller rockers and hardened pushrods, guideplates, etc. I wanted to follow Roger Vinci's instructions for adjusting the valves, from the website, and my neighbor had his own ideas. We ended up somewhere in between, which neither of us were happy with and ultimately found a thread here on the forum that made sense, and was pretty much "old school" style so we went with it. My neighbor adjusted the valves to what he said was zero lash and then we turned the nuts down another 1 1/4 turns and locked them in place. I suggested a compression check at that point but it either went unheard or my neighbor just wasn't interested.

Needless to say, after the engine was all back together and it came time to fire it up, we had zero compression in any cylinder. After arguing about it for a couple of hours, I finally convinced him that the valves were not closing (which it turns out was correct).

So here is where we are at. We had to back the rocker nuts off 1 3/4 turns to get compression in the cylinders. That's 1/4 turn higher than what my neighbor said was zero lash. After the car started and ran for 15 minutes at varying RPMs, the valve train got a little quieter but was still noisy. We then turned the rocker nuts down 1/4 turn and tried to fire it up again. We seemed to have some cylinders with a little compression and some without. It started but ran like crap and was trying to shut off. We then backed the nuts off 1/8 turn higher and tried again. It started but still didn't have full compression so we went back up another 1/8 on the nuts. For those keeping count that's back up 1 3/4 turns from where we originally started (1/4 higher than supposed zero lash).

The car runs now but in my opinion has a very noisy valve train. After driving it around the block at varying RPMs but never really getting on it or going fast, it sounds to me like one or more of the rockers are adjusted too loose. I think instead of being consistent adjustment across the board that some are tight and some are loose.

So, where to go from here? With the engine fully assembled, a nice term would be "difficult" to describe trying to turn the crankshaft at this point. I think I need to remove all the rocker nuts and start from scratch again adjusting the valves with the piston at TDC on each cylinder as I go. I guess I'm looking for advice from those of you in the know. What would you do at this point and what's the easiest way to get that crankshaft turning on a fully assembled engine.

I hate to just try bumping the starter because that isn't very accurate. I know I made a mistake in my "help" choice so let's not go there in this thread. I'd really like to keep this focused and just get some suggestions for how to fix my valve train at this point.

I appreciate any help you guys can provide. I'm an ok mechanic with the older engines but this is my first LSx engine work so I'm being pretty cautious with it. Sorry for the long post.

 

I'd say go back to square one and either go by the service manual or instructions that came with the cam/rocker arms........

 

The service manual is worthless for non-stock rockers and I didn't get instructions with the rockers. What I really need is a secret to turning the crank without tearing everything out of the car that is currently in the way.

 

Check out the "Rocker Arm Upgrade Procedure" in the FAQ.


I guess the FAQ isn't working, so just go to the C6 General section, then click on the Sticky:C6 FAQ link, then go down to the Fluids & Maintenance section, then click on Rocker Arm Upgrade Procedure link. Hope this helps!

 

That does help. I should have gone back and read that again; I'm already using your cut down socket idea but I needed to go back and read the part about the radiator hose removal.

I do have one other question though. Where did you get the 5/8 turn info from for the lifter preload? I wonder if it is the same for 1.8 ratio rockers as it was for your 1.7s? I'm guessing 1 1/4 turns was too much but I can't find any docs for the crane 1.8s. That's my only outstanding question right now. Thanks.

 

It doesn't matter what rocker arm ratio you have, it will still work. Yes, the 1 1/4 is way too much (the valves are probably not closing all the way) and some manufacturers say to use 1/2 turn, that is too little (noisy valve train due to the hammering of the rocker arm tips to the valve stems), so my own innovation is the 5/8 turn which seems to work perfectly. Good luck!!

 

I recently installed Comp Cams 1.75 full roller rocker arms using their instructions and everything works fine. From Comp Cams: "After carefully checking to be sure all pushrods are seated in the lifter and rocker arm, it is time for valve lash adjustment. Adjusting intake valves: We recommend you work with one cylinder at a time. Using the crankshaft dampener bolt in the snout of the crankshaft, turn the engine over by hand in the direction of its running rotation until the exhaust pushrod just begins to move upward to open the valve. Stop rotation. The intake lifter is now on the base circle of the cam and the intake valve is ready to be adjusted. Hydraulic lifter cams: Tighten the polylock until all the slack is taken out of the rocker arm and pushrod. By lightly turning the pushrod with your fingers as you tighten the polylock, you will discover or feel a point at which there will be slight resistance. At this point, you have taken all the excess slack out of the pushrod. You are now at what we refer to as "zero lash." Turn the polylock 1/2 turn more, and while holding it with a wrench, tighten the set screw using a T-handle or Allen wrench. This will give you the ideal preload of the rocker arm, pushrod and lifter. Repeat this procedure for each cylinder and carefully adjust all intake valves. Adjusting exhaust valve: To adjust exhaust valves, turn the engine over until the intake pushrod moves all the way up. Rotate past maximum lift approximately 1/2 to 2/3 of the way back down. The exhaust lifter is now on the base circle and the exhaust valve can be adjusted. Hydraulic lifter cam: Rotate the exhaust pushrod with your fingers and begin to tighten the exhaust polylock. When you feel the resistance on the pushrod, you are at "zero lash." Rotate the polylock 1/2 turn more and then tighten the set screw. Go through the exhaust valves and repeat the procedure carefully. Now all of the valves are adjusted with the proper preload." Hope this helps.

 

Hello,

Remove all the spark plugs, then you can can crank engine over easily with the compression removed.

Adjusting the non stock rockers will be the same as adjusting for stock rockers.

My old 454 adjustment was simple, #1 TDC adjust 1/2 the rockers, than #6 TDC adjust the rest. All loaded to 1/2 turn past first contact. That can be tricky because the hydraulic lifter will start to collapse (push lower) when tightening after first contact is made.

And be careful, you may end up with some bent pushrods.

Douglas in Green Bay

 

I would take it to someone that knows what they are doing!!
So far I have not seen the proper way that's recomended by Crane mentioned.
If in doubt call Roger at Vinci's and have him Fax you the proper instructions.
My Crane set up was 2 turns, 1/4 turn at a time giving the lifter time to bleed down, after the 0 lash was set, turning the engine 1/2 rev at a time.
they are not the same from one RR to another.

 

There are several ways that you can successfully adjust the valves but the above way will be a good way to do it if you don't do it on a regular basis and will be correct when done.


Taking the spark plugs out is the best way to turn the motor over with ease.

 

I have those rockers and it is very difficult to get them set correctly the first time. The easiest way is remove the spark plugs get the motor so that you can turn it over with a wrench. Loosen all rockers. Next turn motor so that valve spring has no pressure on it, and then tighten that one with so little pressure that your fingers barely grasp the bolt, continue to turn the motor and tighten all rockers this way, once you are done with that, and it will take a while. What you are trying to accomplish is getting them to zero lash, but nothing more. Once you have finished follow the procedure to lock down the bolts, easy part. Feel free to PM me or call me and I will walk you through it.

Also I took a socket trimmed it down a little with the grinder, and got an adapter at Sears that will allow you to put an open end on the socket, you can turn the motor over no problem.




Aaron

 

Your helper obviously bottomed out the lifter. Start again from scratch. 1/4 turn after seating is usually the measure.

 

Hydraulic roller set ups require .002-.004 preload on the lifter, any more than that and you run the risk of a lifter failing or holding a valve open. Any less and you'll have a lash setting and a noisy valvetrain plus eventual lifter failure, it's a very fine line. This is an extremely hard measurement to come by just by turning the pushrod or just going with a random 1/4 turn after contact. It's not the same as an older style set up, everything is more precise and on top of that things cost much more when it's done incorrectly. I'd say either take it to a professional that has experience or go with a proven rocker pushrod combination that can be just torqued down (like the stock set up) so that you take the guess work out of your install.

Ed

 

Ok,

I'm just trying to understand this proccess better. I went to this web page:

http://www.ls1howto.com/index.php?article=21

Counting down to picture eight, nine and ten. I read the information next to each picture.

Starting with eight: Once the rockers are sitting in the right place, use a 10mm socket and extension but NO SOCKET WRENCH, and finger tighten the rocker arm bolts until both of the bolts get too tough to spin with 2 fingers. You can take your index finger and try to spin the pushrod under the rocker arms as well, and it should have some friction on it and just barely spin, if spin at all. This is called "Zero Lash" and it is where there is no preload on the lifters....the lifter is touching the pushrod, the pushrod is touching the rocker, and the rocker is touching the valve, all without putting any pressure on the lifter.

Nine: NOW, get your socket wrench out and attach it to the 10mm socket+extension you were using. Without turning the bolt AT ALL, place the wrench in the 12 o'clock position. What we have to do is count the bolt turns until the instant the bolt gets hand tight. Turn each of the two bolts 90 degrees clockwise, then set the wrench at 12 o'clock and repeat (do each bolt one 1/4 turn, and keep alternating).....each 1/4 turn per bolt seems to equate about 10-12 thousandths preload (this is a very rough guess!).

If you get MORE than 1 full 360 degree turn on each bolt, remove the rockers and install the shims on the bottom of the pedestals and repeat this process to check the new preload. The shims seem to reduce the turns by approximately 270 degrees. You must install a shim on BOTH bolts, not just one or the other. If you got LESS than 1 full 360 degree turn then you are ok to leave the shims out!

Every car will be different so make sure you check this! You want the smallest number of turns you can get, as long as you have at least 1/4 or 1/2 full turn of preload in there once you are all setup. If you get to the point where the bolt is tight yet you can still spin the pushrod (without using shims), then your pushrods are either too short, your valves are too short, or you have some strange valvetrain geometry. You MUST have some preload or it will be OBSCENELY loud and run very poorly. Longer pushrods may fix your issue in this case.


Ten: Now that we know if you need the shims or not, we don't need to do ANY of that legwork above on the other 7 cylinders...we can just throw the rockers on and go (either using the shim or not, depending on what you found out above). So, do just that....bolt up all the other 7 pairs of rockers (if you have ported heads, you may want to use a little locktite on the bolt threads). Remember, since these other cylinders are in totally random positions, it is 100% normal for the rest of the rockers to compress some valve springs as you start to tighten the bolt down, since these valves aren't all shut. Using a small socket wrench, tighten all these bolts down. You should be able to feel when the rocker seats itself as the bolt will stop turning if you are using a small socket wrench.

Once the rocker arms are all seated, get your torque wrench out and set it to 22lb/ft and torque all 16 rocker arm bolts to 22lb/ft. Go over the bolts a couple times to make absolutely sure they are torqued to spec.


Ok, now I've finger tighten the rocker arm bolts until both of the bolts get too tough to spin with 2 fingers. I'm at "Zero Lash"and it is where there is no pre-load on the lifters.

Now, I'm set up for my 1/4 turn, I've turned it twice, until the instant the bolt gets hand tight. I've made the smallest amount of turns.

Now, I'm set to torque the bolt to specs (22lb/ft) and torquing makes another two turns for a full 360 rotation of the bolt. Is that ok or am I just not suppose to go over 360 degrees when initially hand tightening?

 

is there a reason why you won't do it crane's way? your "zero lash" is to much! loosen all! with fingers tight just touching NO MORE!!!!!! rotate engine 1/2 turn REPEAT a few times then a 1/4 turn ten minutes, 1/4 turn ten minutes until you have done it 8 times TWO FULL ROUNDS and then wait a half hour before starting it up




NO! NO NOT WERE YOU CAN"T TURN IT WITH YOUR FINGERS, just where the lash is gone!!!! GENTLY !GENTLY!

 

Cranes way is the right way!!!

 

I didn't realize you could still find documentation at Crane's website. I thought everything was already taken down since they were out of business; at least temporarily. I think I found the right documentation for these rockers though Here.

The doc specifies "LS1" rocker arms but I think these are the ones I have in my LS2. I didn't get part numbers or a box with them.

It looks like the instructions here go hand-in-hand with what was on Vinci's website but this didn't work for us. I can only assume that when my neighbor went to "zero lash" he was way past zero lash to start with. I'll give it another try tomorrow I guess. I want this done right. I had absolutely no problem adjusting my Comp Cams rockers in my early 350 SB but this LS engine is a new ball game to a certain extent.

 

Stock rockers don't require adjustment.

 

Ls engines do not require adjustment, if change the head geasket thickness or shave the heads, all that changes is the lenght
of the pushrod!!!

 

yes their listed as LS1 rockers, NOW gently!!!! you don't want to push down on the lifter, I just did mine several times and at first I had a few too tight but I caught myself, now I seem to have more noise then before but I also put in new regular spark plugs and I think I'm hearing those because the car runs better then before!!!!!! the stock plug wire's are crap I had a couple of bad one's and had to replace, it idle's better then it ever has!