Georgies

I tried cylinder 1

Something is really wrong..

Intake 7.2875 calcullated with turns (7.300 with vernier)
Exhaust 7.2625 calculated with turns (7.276 with vernier)

Im thinking im not at TDC BUT I AM.
or maybe the lifter plugers is depressed?? Is it possible the motor has been sitting to long? Is it possible i didnt install the cam properly?

I need help please!

I will rotate the crank another 90 degrees and try piston 8 and 5...

Georgies

Im still getting conflicting results.

I did piston 8 and 5 after rotating the motor clockwise another 90 degrees.

Piston 8:

- Intake: 7.325(vernier tip to tip) or 10.25 turn
-Exhaust: 7.261(vernier tip to tip) or 9 turns

Piston 5:

-Intake 7.380(vernier tip to tip) or 11.33 turns
-Exhaust 7.361(vernie tip to tip) or 11 turns

I rotated the motor another 90 degrees to get pistons 4 & 7 at TDC.

Piston 4:

- Intake: 7.379(vernier tip to tip) or 11.25 turns
-Exhaust: 7.360(vernier tip to tip) or 11 turns

Piston 7:

-Intake 7.318(vernier tip to tip) or 10 1/8th turns
-Exhaust 7.270(vernie tip to tip) or 9 1/8th turns

Too frustrated to continue...Will keep going again tmr with piston 3&2 and again, 1&6..maybe im not perfectly at TDC.

Or maybe this MS4 cam is not accurate?

Thanks for all the help

vettenuts

Is the timing cover still off the car? If yes, then concentrate in cylinder 1 and 6 since you can see the timing marks for those cylinders.

Try another method to examine your conflicting data. First, before starting the measurement and installing the rocker but after you have put the piston at TDC for that cylinder, put in your stock pushrod and push down on each lifter for that cylinder to ensure the lifter is touching the cam. You will hear the lifter "clink" if was not in contact.

Then, use the adjustable pushrod and slowly open using a 0.010" feeler gauge under the rocker tip. Once at zero lash with the feeler gauge under the rocker tip, remove the feeler gauge (should have very little resistance if you are at zero lash) and give the lifter about 5 minutes and then re-check with the same feeler gauge. If the lifter plunger wasn't depressed, then the feeler gauge will go back in with very slight resistance. If you can't get it back in, then the lifter was depressed during your measurement. Find out what feeler gauge will fit and make a note its thickness.

Then use the method of measuring at zero lash you were using before and take a measurement again.

Georgies

Yes, the timing cover is still off the car. did not want to put it on till the pushrods were done and valve covers back on..

Ok got it, will try that as soon as i get a chance. Thank you very much

helga203

Just curious, why not go to adjustable rocker arms??? Then it doesn't matter the length of the rod. Or that can't be done??

Georgies

im kinda way over my budget with these mods...id really like to get the car on the road and the only thing halting the job is the pushrods right now

Georgies

Vettenuts, will the lifter re pressurize itself when i turn the motor over by hand? or will time get it back to normal?

Georgies

1ok i turned over the motor till cam and sprocket markes lined up as best as i can.. looks dead on.

Started with cylinder #1

Pushed down the lifters as I did in the past but this time very delicately.

Used a .010 feeler gauge under the tip of the rocker until I found zero lash. The rod would spin just a little and no tap at the tip.

Pulled out the feeler gauge and waited 15 minutes. When I put it back in it felt like exactly the same resistance.

I then proceeded to readjust the adjustable push rod to compensate for the feeler gauge.

-Intake = 7.285 (vernier) or 9 & 1/2 turns
-Exhaust = 7.280(vernier) or 9 & 7/16

Results are good from intake to exhaust(meaning they are close)

Now here is where I'm lost.. I went ahead and did the same thing for cylinder#6

Feeler gauge went in with the same resistance 15 minutes after finding zero lash.

So went ahead and readjust to get zero lash without feeler, result are very different than cylinder #1 !!

-Intake = 7.377(vernier)
-Exhaust= 7.355(vernier)

What the hell is going on??

vettenuts

Depending on where the timing marks are, both piston #1 and #6 are at the top but only one is at TDC. Since the cam has some overlap, the valves on 6 are open. If you haven't moved the motor since measuring, rotate the timing mark on the crank for one full turn. If the cam mark is at 6 o'clock it will move to 12 o'clock. If its at 12 it will move to 6. Then remeasure cylinder 1 and 6 again and I think you will find your measurements will reverse.

Georgies

Thanks alot man. Youve been so helpfull!

Georgies

I'm pleased to say that I just turned the crank 360 degrees( Cam mark @ 12, crank mark at 12) and Vettenuts is right on the money.

The measurements have reversed.

I may be a little off as I'm really trying to get zero tap but still maintain the ability for the push rod to swivel.

so
Cylinder #1
-Intake : 7.370(vernier)
-Exhaust: 7.355(vernier)

Cylinder #6
-Intake: 7.283(vernier)
-Exhaust: 7.283(vernier)

I'm guessing i should use the measurement of the longer push rod?

Also, should the preload # that I'm supposed to add to the length when ordering be greater than the distance of the longest and shortest push rod length between cylinder banks?

In this case 7.370-7.283 = 0.087

So my preload should be > 0.087 ??

What should I do next?

helga203

what springs are you using?

Georgies

This is the description from the sales order

vettenuts

In this case, you should ignore the cylinder #1 values because cylinder #1 has the piston at the top but not on the firing stroke so the cam is actually holding the valves open due to the new cam overlap. The cylinder 6 values (7.283) are basically the same as your prior cylinder 1 values (7.285 & 7.280) so that is your base pushrod length. If you want to double check, you can rotate the crank 90 degrees and check the next cylinder in the firing order. You should get the same values (within several thousandths of an inch).

Georgies

I will double check the next 2 cylinders. What should I order then? How much preload should be added to the length of the push rod?

I'm thinking that from the point of torque I applied by hand to 22 ft-lb might be 0.002 - 0.004 of downward distance into the lifter...

Should that amount be taken off the preload #'s?


I spoke to Al at Manton, he told me to check push rod length at the for corners(8,2 and 1)

and to call him back. He was saying to get different exhaust and intake rods.... I'm not to sure I wanna do that LOL.

Vettenuts, what would you do?

vettenuts

Your numbers between intake and exhaust should be close and consistent. Get you final values. If you have stock lifters, I am not sure how much I would run since I am running Morel lifter. However, the stock value is close to 0.100" preload but many have found a lower value works better. I would do some searching and see what others are running as there seems to be two theories on what is best. From what I have read, 0.080" preload seems like a good number.

If all measurements come out how I think they will, you should have numbers close to the 7.283 value for your zero lash length.

1Hotrodz

Don't want to confuse the issue but, Is the cam a re-ground core with an undercut basecircle? Or a new camshaft?

vettenuts

I believe he installed an MS4 cam, so it would be a new core. Not too many reground cores around like the early days of the LS1.

vettenuts

One other recommendation when you order your pushrods. Also get a pushrod brush for cleaning the inside of the pushrod where the oil comes through and get some Assembly Lube. I like the Redline Assembly Lube because it dissolves very quickly when the oil reaches it, but get one without particulate in it. Use the assembly lube under the rocker tip and on both ends of the pushrod. Clean the pushrods thoroughly inside and out prior to installing.

The lifters will make noise when you start it, just let it idle until the lifters quiet down. It could take several minutes.

Georgies

Is it possible my numbers arent accurate because of the fact that im using the designated exhaust rocker per each cylinder.

I oraganized them when i took them off and didnt think that it could effect my measurments. I also did the CHE trunion upgrade on em....