What are you high HP guys doing for a timing chain? Ive heard mixed reviews about spending the money to upgrade to a heavy duty unit...some say you need some say you dont. What will kill a timing chain? The HP? RPMs?

Im not going to go with an electric WP so I only have a couple options....

What do you guys think?

 

get ahold of jason cromer the extreme duty set is like 200 and the standard set id $180. I just ordered it from him last week. If you run the stock waterpump it's the way to go.

 

I'm running a 383 pushing a guestimated ~415 rwhp with the LT4 extreme duty and I haven't had any problems so far. I won't go to an electric pump either cause I can't afford to replace it often cause I drive my car alot, sometimes almost 1k miles a week. Sometimes I kinda worry about whether it will hold up, but I really don't have any other choice but to use it.

 

AFAIK, high RPM will kill the timing chain.

 

I'm not particularly 'High hp', but I did throw on a Cloyes dbl roller when I did my XE cam swap..

I don't think the problem with the stocker is it being weak so much as it is a stretching problem (I could be wrong, if there's a rash of folks with broken stockers out there, by all means - speak up!).

The problem is they tend to stretch very quickly. A buddy of mine did a stock replacement on his 96 when he did his cam swap. 5000 miles later he did a 383 build and the stock replacement chain was already stretched. That little lesson was the only reason I went with a Cloyes and not a stocker set.

 

Hmmm...my stocker was just replaced 6K ago and is still very tight...

Anyone else?

 

How high do you plan on spinning the motor? Also what hp are you looking at?? I was pushing 500rwhp and running a stock chain with no issues (shifted at 6000 rpm). I decided to go with a Cloyes 3145 when I upgraded to a 95 style opti.

 

Im shooting for 430-450rwhp and max shift RPM would be 6500....although I wont see that more than a couple time a week...

 

I just took off my original chain at 57K for the cam swap, that thing had a lot of slack in it, I was pretty surprised at how loose it was. I went with the Cloyes double roller, I could barely get that thing on it was so damn tight!

You're only real option for a heavy duty chain is the LT4 ED if you'r sticking with the stock wp.

 

If you go with a cloyes you need to go to OBDI too right b/c of the CPS?

 

No, you just need to have the CPS programmed out. I havn't done that yet but I have an SES for it. I need to have PCMforless redo mine soon for other changes and he said he can just remove the CPS. It just detects misfires for emmissions testing, doesn't effect engine perfromance at all. I may switch to OBDI eventually though anyway, I'm moving soon and the new county doesnt have any emissions testing.....Yay!!!

 

I read a post a while back where some guy said after heavy abuse, with high rpms, I think around 62-6400 rpm, he took the chain out after a great deal of miles and was surprised how tight it still was, and so replaced it with another stocker. I'd say as long as you keep down the rpms you'll be alright. I don't think reving up to 6200 rpm couple times a week will be a good idea, I think thats risky. At most you will only destroy your engine, I personally am waiting for that day, so I can rebuild mine better, but thats me.

 

I'm running the LT4 extreme duty. I got a electric H20 pump after I installed it. Next time it will be a Cloyes.

 

I'm running a LT4 ED with a Cloyes oversize crank gear in my 396. The gear was only $30 shipped, and takes up the slack that GM seems to purposely engineer into their chains. I'm happy

 

Interesting Ill have to look into this since all my CPS did last year was give me trouble...hmm