nolimits

Have seen the thread in Tech about a timing chain failure on an LS2. I'm doing a lot of lapping with cam/dual springs, head, exhaust, intake... mods.

Many of you road racers had chain issues, any recommendations? Mine is stock now with 9,000 miles and I'm going to do a cam swap soon so will be in the chain area. Have heard of dual spring options and some single options. Hear the ZR1 still uses the same French chain as the LS2 so maybe I'm ok.

Does addl hp stress the chain more?

RC45

Katech C5R chain and dampner is good insurance.

Wicked Weasel

First I like to say there is not A LOT of chains breaking. There have been some chains breaking under aggressive driving when you are shifting up and down.

That being said if you are doing that work I would look into another chain. Katech mentioned that they have never broken a C5R chain. You can also look into the damper that helps stop the chain from flexing.

For springs I would go with the 921s. We have been running them in all of are RR cars without any problems. They cost more, but since they are holding up it is worth the money.


As a side note if you are planning to run a lot of days you should think about replacing the chain and other valve train components much more regularly than before. I know my LS7 setup is going through an inspection each winter and I will be changing the timing chain.

96CollectorSport

I had a friend break a LS2 chain at Mid-Ohio, I also heard that one of Raftracers guys broke an LS2 chain as well, but I haven't talked to Danny since to confirm. What's crazy is that before this year I only heard of 2 or 3 LS2 timing chain failures then we have 2 go in one year (with dampeners!!). I think that the Katech chain is what I would look into if it were my $$$$, the timing chain takes more abuse in our cars than any part of a racing engine, think of the shock everytime you get on and off the gas, every gearshift, every heal / toe, that's a lot of back and forth action.
One little note about dual springs, depending on which valves you are using, you may not need duals. PSI makes some great single valve springs that have been track tested, Wegner Automotive used them on all of there NASCAR LS2's, and never broke one. So if you are looking at running stock valves the PSI's would be the ticket (duals would be way too much spring for LS3/LS7/or LS6 valves), but if you are running aftermarket stainless valves (or LS2) then the 921's would be the way to go. Reason being the LS3 and LS6 intakes are hollow and the LS3/7/6 exhaust valves are sodium filled, too much spring pressure can cause a valve failure. The LS2 valves are solid both intake and exhaust and can handle more spring.
These are just a couple of lessons learned along the way, hate to see the same mistake made twice.

nolimits

FYI I'm running the A6 automatic, ok no shots you manual shifters, It beats Z06s right now and with more work coming is quite a combo.

Is the C5R chain dual? Any install issues? Where do I get one?

Thanks

davidfarmer

JWIS makes a drop-in replacement chain, and it was suggested to me by a GM Racing rep back in the LS6 days. It is completely drop-in, so no gear changes needed....worthwhile upgrade if you have the cover off for any reason.

2nd down in the link

http://www.thunderracing.com/catalog...vid=3&pcid=222

DALE C

I thought the LS2 chain was the old C5R chain from GM performance parts part numer 88958608 or new number 12586482, they are about $30. Not 100% sure but I would look into it. I have never had a problem with the Coyes or LS2 chains. I can tell you we have put the Coyes to way more abuse though.

nolimits

Thanks All !

blue383

The timing chain broke in my Lingenfelter 403 earlier this year. The chain was a stock LS2 according to LPE. My car had only a little over 7K mikes & 10 track days. My C5 with a Vette Doctors 383 had 40,000 miles on it and was used in over 70 track days over 6 years - no mechanical failures. LPE rebuilt the motor and has replaced the chain with the C5R part. I paid a portion of the cost since LPE has a disclaimer in their warranty for a car that is used on track.