mcm95403

The thread title pretty much covers it - what is the common cause of timing set failures. Also, which timing sets seem to work best to remedy the problem?

Jnape

The harmonic balancer has a bunch to do with it. Stock ones taking a dump or an UD pully of certain brands have been a likely cause of failure.

69SSC5

common cause is bad harmonics, i.e. spending alot of time between 3,500-6,000 or so RPM's. I have always heard that this RPM range play's havoc of sorts with the harmonics of the motor. a busted chain is not a common problem for those that don't road race (scca or other). there are some rumors on the internet that say a certain brand of UD pulley is the cause of timing chain failure but when you dig deeper you will find that most the guys that bust there timing chain race their car. there is only one true harmonic damper for the LS that i am aware of and that is the ATI super damper

printmanjackson

I think the stock timing set is crap! chain has slop and sprockets are not that great.

Cloyes makes a nice set with billet sprokets and the LS2 chain, has adjustable timing for the cam and there is zero chain slack

The only dampener for an LS engine is the ATI. Do your research and you will see.

69SSC5

True harmonic balancer yes. What other true harmonic balancer do you know of? not powerbond, not asp. I agree about the hex adjust timing set, great timing set

Bill Curlee

The STOCK OEM LS1 chain just plain SUCKS! It stretches very easy and when there is a lot of slop in the chain, the chain tries to wrap up on its self on the slack side of the chain when you change from acceleration to deceleration and vise versa.

The rollers on an LS1 chain are NOT solid!!! If you compare the LS2 chain (installed) and the LS1 chain, you can see how inferior the LS1 chain is.
If you look very close at the roller (top chain roller between my two fingers) you can see how the roller is NOT solid and has a parting line.

They frequently split in half and fall into the crank case which leads to chain failure. The LS2 chain is a little more robust BUT,, its by far NOT the best chain that you can run if your going to run the car very hard.



I have it in my 02 Z and it seems to be holding up very well!

I was one of the lucky few that got to order a chain dampener before they vanished from the GM parts counter and my block was factory drilled to allow me to install it. It helps to control the chain slap that promotes chain stretch and stress failures:



BC

vettenuts

Timing chain damper (no longer available but Katech had some several months ago) and the harmonic damper are the key components. ATI or stock per Kurt Urban who did a lot of work with the broken timing chains in the road race cars. ASP seems to have strong correlation with broken timing chains and I would avoid.

bracketshark

I bought and installed A rollmaster (billit) single roller timing set, it tightened everything up no need for a chain dampener with this setup. I ordered a Katech chain first and the same slop was on that chain as the stock chain, it was unacceptable for me, I'm very satisfied with the rollmaster. Now why do chains break, along with balancer issues I think being on a rev limitor in excess has a lot to do with it, this is another reason Nascar went to belt driven timing sets. JMO

ZeeOSix

So the '02 LS1/LS6 didn't have the chain dampener? What engines and what years did from the factory?

Bill Curlee

I think 05+ did and the LS3 has an entirely different chain dampener.

The 05, 06 dampers look very simular to the dampners for the LS1/LS6 except its black and has a different hole spacing and will not fit LS1/LS6 blocks.

Check out POST#4. Itshows the LS2 Balck Dampenerhttp://forums.corvetteforum.com/c6-t...tensioner.html

Check out POST#29 for GMs latest chain dampener!

http://forums.corvetteforum.com/c6-t...er-damper.html

printmanjackson

I went down this road and in the end bought the ATI dampener and the Cloyes hex adjust timing set

vettenuts

Some special/early 97's did as well. It was part of the motor but removed to save cost. Some early cars made it out of the factory with the timing chain damper in place. Someone on LS1tech was building them, not sure if he still is or not.