DetroitPlac

Unfortunately like @helga203 mentioned, it seems to be somewhat hit or miss. Shorter ones helped me, longer seem to help others.

I'd consider this...

MOST shoot for preload on these things around .070". Measure how close you are to that and change the pushrods to compensate. I'm right around 0.65 preload and it's rather quiet.

bwill03z

I ordered a pushrod length checker and should be in tomorrow. After determining what preload I am currently running I will decide if I need to go with more or less. If my current preload is on the higher end, maybe around .090, Could a lower preload actually be less noisy? Maybe go to .065? Because if I am currently around .090 then going up a pr size would put me over .100 and that would be too risky, correct?

DetroitPlac

That's how I approach it.

evolmotorsprt

I think you’re on the right track, one more thing though. Are you running stock injectors? Some injectors can be terribly noisy and can sound like lifter tick, an exhaust leak, etc... I have a 228r and deatchwerks injectors. My injectors are louder than my valvetrain.

bwill03z

Yep, stock injectors. I considered that and I know the injector tick adds to the overall noise of the motor but the loud clacking I’m concerned about definitely isn’t the injectors. I know the 228r cam has a smaller base circle than the stock ls6 cam so I don’t imagine the 7.400 pushrods I have in there now could be too long, I’m hoping they turn out to be just a tad short and going up a size will help. It’s just hard to say because I also added ls7 lifters into the equation which I have been reading a lot of conflicting info on. Some say they measure identical to the stock ls1/ls6 lifter and then some say there’s a .040-.060 difference so I really don’t know what to think

Tusc

Not for nothing, but better safe than sorry. I just bought a 2003 Z last month. Heads, cam and intake with a blower. Two days into driving it and a lifter collapsed. But a day before when idling the car in a friend's driveway he thought he heard a louder noise like you say. I passed it off as typical sewing machine chatter.

Pull your covers and check that no rockers are loose and no pushrods are too deep.

Bill Curlee

YEP!! Also, when the cylinder is on the compression stroke, (both valves shut), see if you can push down on the rocker at the pushrod side. You should NOT be able to feel any give if the lifter is properly holding oil (not collapsing) If it is able to depress, that lifter is bleeding down (bad)

bwill03z

I will definitely inspect it o be sure but it’s unlikely that it’s a failing lifter. These are new ls7 lifters that I just had put in and the extra noise In heating doesn’t sound like a tapping lifter to me.

bwill03z

I did Some measuring this evening and by my calculations I am between .085 and .090 on preload with the 7.400 pushrods. I only got the chance to measure on one cylinder so I will do more tomorrow . It took 10 and between a quarter and a half turns to get to zero lash. I assume going up a size and going over .100 preload is prob too much? I guess I may just have to deal with a noisy motor.

Speedy007

I used c7 lifters rated to 800hp
.51gasket
stock lengths hardened rods by ZZ Top performance. 7.40
all with new 243 performance gm heads/ kept the springs and valves.
If I heard a sowing machine noise maybe check out the rocker arms. Possibly you have some loose or worn out parts.
Mines quiet as ever. Before I changed mine I was getting a small lifter tick upon start up. I had a buddy his slapped like a sowing machine until he tightened down the rocker arms. properly. That was a 302 boss. If the lobes weren’t done when doing the cam then that could be it and that becomes time consuming again. Your cam could be slapping from worn parts. A 228 wouldn’t be my first choice your better off with a custom cam according to what you have and what your looking to get out of your poweband. If you have to go the distance. Check your springs maybe they are worn or need a dual coil/ beehive style replacement.

bwill03z

All the rockers are stock but none have any visual wear. The pushrods, lifters and dual springs are all brand new. I don’t know what else could be worn.

Speedy007

I would check them one by one for wiggle there’s plastic with a bearing I think inside those rockers and it wears out. Re torque and see if any changes it will prob take you a hour. .650 coils? On stock valves ?

bwill03z

They all wiggle a bit side to side... all rockers have be retorqued. Also I did the bronze bushing rocker trunnion upgrade. Springs are TSP dual .660 springs, and yes stock valves

Speedy007

Any change ?

bwill03z

Nope... on a cold start everything sounds pretty good, some sewing machine noise but not terrible, but when the oil heats up that’s when it gets noisy

bwill03z

So I think what I’m dealing with here is an issue only on the driver side. I’ve been outside listening carefully and the ticking begins only on the drivers side and that’s why I can hear it so well when driving. The passenger side seems to be pretty quiet. It’s sounds like maybe just one pushrod is a hair too short. Probably not hurting anything but it’s enough to drive me nuts

DetroitPlac

Check a few other cylinders on the driver's side just for science to see if there's variation per your other post about driver's side. You might benefit from a little less preload from 7.375" rods

BTW, mine also gets louder as the oil warms up. I found running 0w40 Mobil 1 over 5w30 helped quiet it down a bit.

Speedy007

Could you post a new video up here with the car running. I really would doubt you have 1 rod smaller than the rest. I would suspect those.660 dual coils are to much spring.Maybe it’s not able to perform is action properly.

bwill03z

I have been considering m1 0w40, May give it a try... I don’t see how running a shorter pushrod could possibly produce less noise, but then again I’ve heard other ppl say they had luck with less preload.
Yea I will post one shortly. Possibly but those were the springs that came in the package. The 228r cam I have is a .600/.600 lift though.

turabo87

My driver side is the one that is a little more noisy too. Bwill03z, have you checked recently your exhaust beneath the car? Reason I say is that I found out that my X-pipe/mid-pipe is actually not centered on the tunnel, but rather it's offset towards the left of the car so much that it's actually pressing against the left tunnel wall. Literally, it's a compressed interference fit on the left. That said, my C5 has therefore an unwanted, increased valvetrain noise and exhaust noise that comes from the vibration resonating directly onto the tunnel and amplified to the cabin from this direct contact. I found it two weeks ago I went by an exhaust shop to check for leaks. Still haven't fixed this issue since I need to go back for another appointment for it, but when the x-pipe is not in contact with the tunnel wall it is obviously a lot quieter. FYI, I have Texas Speed headers and X-pipe, but regardless your brand this might be something worth checking.

PS: Have you given the Rislone a try? I also have brand new LS7 lifters and this helped for me at least.