I dont believe that the fuel injectors are what is making all this noise. My AIR check valve is not making much after I built a restrictor for it.

Im willing to believe that a different oil makes a diffrerence though. A long time ago one of the vendors I didnt have such good luck with told me to run a slightly heavier weight oil to quiet the valvetrain alot. I never tried it.

Im going to call a few of the better vendors around and see if I can get their opinion on this as well. I'd like to have some kind of concensus on this on the board rather than a big mystery hanging out there.

chris

 

Withmine it cant be the AIR or restrictor plates Becasue I dont have them. And its not associated with the larger valve, dont have them either...I contribute the noise to the valvetrain slop...rockers/prods/springs and lifters are not in their happy spot. Headers before cam, no noise, after cam, lots o noise...Its all relative to the preload in my opinion.

 

As soon as I get a few break in miles, this is what I was gonna try. I think mine is the Comp Cam lifters. Cam is LS6 - not that big, and didn't make this amount of noise when I had the stock lifters.

I don't have air tubes, so it is not that. I know my forged pistons slap like anything when cold, but that goes away when warmed up.

Sounds kinda like a truck now according to my wife

 

Bingo!

 

my H/C valvetrain is NOISY!!!

over time it has come down a little (or either I have not noticed it as much).....but its still LOUD...

parts:

- TR224/224 112LSA
- stock lifters
- 7.400" chrome molly pushrods
- stock rockers
- 2.08"/1.60" valves
- Comp 987 duel springs (inner, outer, dampener)
- rollermaster double roller chain


a friend of mine has stage 2 heads (smaller valves) but with a TR230/224 111LSA cam and his valvetrain is much quieter than mine.....so this leads me to believe that my noise is comming from the larger valves and their seats.....

I have considered doing rockers to try and get rid of the noise but I just don't see it being worth $500+.....

 

yeah, I too have 2.08s, and Im thinking they certainly do conrtribute.

I wonder what length pushrods I have. I know my heads have been milled *alot* since I had to alter the LS6 intake to fit between the heads.

chris

 

ok I want to get some things clear. air check valves keep the vacoom where it needs to be correct? But where are they? And I didnt know that injectors could be heard, what do they sound like??

 

I just installed the Yella Terras and it made a big difference. Although now I have a loss of 15 rwhp. It is very quiet and smoother than before w/ my H/C Vette. Cam is a 224/224/-581 lift 112 ls.
I am not blaiming the rocker for the HP loss still tring to find that one. Think its plugs and low gas issue.

 

TTT

 

Chris-

I think valvetrain chatter can be from any of the following:

-Fast ramp cams
-Minimal lifter preload, like zero lash
-Increased noise going from stock manifolds which are doublewalled to single wall headers

My S1 was a ton louder than it's predecessor Lunati 242/242//114. Same preload.

I put Y/T's on my current engine, but I have like 10 minutes of run time on the motor.

 

Im going to put some yella terras on, even in the off chance that they will be quieter. I'll try and come up wiht some objective way to measure the noise, but I doubt it will be easy to decribe.

From the Vendors:

Aftermarket Lifters make a big difference since they like so much less preload.

2.08 valves are noisier than 2.02, etc.

Fast ramp rates make a big difference, but there is no other way to great power.

While noone on the vendor side has said they htink YTs will quiet the valvetrain, they have sene most get louder with Cranes, etc.

So far, I have almost every possible thing going against me... Large valves (2.08), Comp R lifters, stiff springs, headers, and a mean ramp rate on the MTI X1.

urp.

chris

 

most of the noise is from the "heavy" valves slamming closed off of the ramp of the cam that's why GM went with a lightweight valve on the 02 Z06 to keep the noise down as well as valvespring life

jay

 

Mine is quiet;;;

Terra yellows
Crane R lifters
Lunati double springs, Ti retainiers
LS6 valves
Hardened pushrods
220/220, 564/564, 112
Rollmaster double chain

 

Ok, I'm going to have to disagree with some of the stuff here. I've had more combos, more cams, more heads, more sets of pushrods, more sets of headers, etc than I can count.

1) Valve size seemed to matter NONE. I went from stock headed to ARE 2.08 valve headed, and valvetrain noise increased zero on the given cam. I then went to a 2.02 valve and and more aggressive ramp rate, the noise increased a lot. Valve size seems to play no part in this, or at best, a ver miniscule part.

2) LIFT does not make a cam noisy! Its ramp rate. You could have a 0.500" lift cam that'd be noisy as hell, and a .580" lift cam that is quiet.

3) Lifter preload probably does matter a little (or a lot if you are running none), but after throwing in 3 different sets of pushrods, the sound was the exact same on all 3. 0.120" preload, 0.70" preload, 0.20" preload, it didn't matter. The stock lifters quite simply didn't care. I tried the same with CompR lifters after a head swap, same deal. Car ran fine either way, even dynoed the same!

4) YT rockers will probably quiet it down by maybe 5%-15%. Its hard for me to say since I've never installed a set on my car, but the set I did install still sounded noisy to me. The owner of the car however said it was a tad quieter than before, so I'd imagine its worth something there.

5) Headers don't seem to affect valvetrain noise. They do add lots of engine bay noise and noises from under the car from exhaust pulses, but the valvetrain noise itself was loud when I had stock manifolds, and its loud when I had FLP's. Zero perceived change there.

6) Visceral, your car sounded fine to me for the combo you have. Your valves/headers/preload IMO has nothing to do with it. Throw a softer lobed cam in and you're set. My 230/230 .566/.566 112lsa cam was quiet as can be because it didn't use the fancy high ramp rate lobes that are so popular now.

 

I have the Camaro, you have the vette. I like it really quiet and you dont mind the noise.

How messed up is that?

chris

 

I mind the noise, trust me...its annoying, but what I'm saying is that there isnt much you can do about it short of going with a different camshaft.

Dynomat your engine bay.

 

I did a little more testing today.....got out the stethoscope and an aluminum bar to try and "locate" the sound....


I worked around from the valley cover (front part exposed by intake), up the heads, to the valve covers, and then finally to the header....

To me it HAS to be the valves snapping shut hard (fast ramp rate, stiff springs, and large valves on hard seats).....




precedure:

1) At the lifter valley it was "fairly" quiet (mostly head what I take to be chain noise from the double roller)....

2) when I move to the head (started at the bottom), I heard the "crack" of the cylinders firing but in the "background" (very light over the other noise) I heard a "ting ting ting" sound.....as I moved up the head (closer to the valve cover) it died down.....as if I got farther away from it.....

3) I moved to the valve covers and NOTHING....just "typical" internal combustions noise.....nothing metallic or ticking of any kind...

4) finally I jumped down the headers (hooker LTs) and sure enough, along with that BEAUTIFULE LS1 exhaust note (a little loud though) .....TING TING TING.....sped up as I increased RPM (slowly rolled throttle).....sounds exactly like striking a bell....



I remember before I installed the valves (first came in the mail) as I was getting them out of the box I lightly struck them together and they rang like bells....really good tone I might add.......

 

JMX:
How is the documention on the Viseral long-block swap going; many here are anxious to see the results?

********
I have Lunati double springs, Comp R lifters, LS6 hollow valves, Terra Yella's, and a smallish cam 220/220, 564/564, 112.

My valve train noise is about the same as a stock car...very quiet...

 

We took a load of pictures, but Jon and I are going to have to do aloooooooooooot of work to make this a worthwhile document. Since it is only an engine IN peice, jmX thought about calling it a Journal. Its not a trivial job, and jmX only likes to put close-to-perfect docs up on his site. We were thinking of an aftermarket Torque arm howto, but I had already disassembled the TA mount on the tranny, making the result too easy for the howto. Jon hates the idea of making the doc half-assed, so we bagged the TA install idea.

You can imagine that Jon will post something right away when he gets it done

chris

 

As Visceral said, Its mainly going to be a photo journal of the steps, not a how-to. I'll show where sensors transfer to, what some of the bolts are, how we put it in, etc. It won't be nearly as detailed as other stuff on the site.

Anyway, I'd say its at least 2 weeks off...I've got more important writeups to do at the moment. I do have loads of pics tho and the whole thing is on my to-do list.