Has anyone tried the GMPP timing chain&gear set? I would like to know if its worth the asking cost and if you can still use the factory cover and gasket or does it require a different cover?

 

idk abouy that but if its specifically for an LT1 it should be fine.

 

Its for the LT1 but it says on the website, "not a factory replacement", which makes me wonder if it requires shims or shaving the face of the block for fitment.

 

Are you talking about the LT4 Extreme Duty one? I have one. It is a very nice piece and I don't think it will stretch out like a stock one will.

 

Yeah, thats the one Im referring to. Was it a simple bolton and go or does it require some mods?

 

Stick with a new stock set. No need to upgrade to a Extreme Duty one. A new stock replacement will be just fine. I have never had any issues of the stock one stretching.

 

It's only worth the cost when you start exploring RPMs and HP past where the stock LT1 is capable.

I went with the Cloyes for MUCH cheaper, although you need to use an electric water pump.

 

My motor has some mods, its a 355 with bored intake, and ported heads with bigger valves, LS7 lifters, and a 600" solid roller cam. I don't want a double roller, so I figured this would be the next best thing. I just don't want any surprises when I start to button this timing set up.

 

Has anyone ever heard of a stock timing set up failing? I just replaced mine with stock parts while I was in there.

 

Not I...just took my stock timing chain off w/ 60k during my LE2 swap and it looked just as good as my new one. Sprocket looked to be in great condition as well.

 

its cheap insurance if your going to spin the motor up to 6700. This is why i run the lt4 chain, plus you can run the stock waterpump, which i like better for the street. if your going to keep rpms down around 6k, then a stock replacement should be fine.

 

Does it require any extra mods for installation?

 

None that Im aware of.

 

It is good insurance but Ive never heard of a stock chain or sprockets failing no matter what rpm. On my 396 build I will be using a HD timing set up but I plan to spray the **** out of it. Untill then everyone I spoke to basically said the same thing HD is good insurance but nobody has heard of a stock set up breaking either.

 

I agree, I just went ahead with it because it was recommended by my builder. He also recommended only running 20w-50 vr1 oil. If I was the Op, I would call a few reputable engine builders and pick thier brain with these questions. Everybody seems to have there own opinions on this board, and these debates always lead to arguments because someone is always quick to tell another they are wrong. BTW Ac Im not implying you are doing this at all!

 

no modifications needed i have pics of it installed in this vid @ 3min mark.
http://videos.streetfire.net/video/L...847_175195.htm

 

Its all good. Im doing one on my next build so I have mixed feelings. I was hoping someone does say they broke one, to justify the extra cost of a new one.

 

ive got a buddy of mine that his let go last weekend. now dont quote me that the chain failed, i want to go inspect it when he tears it down. now granted, he was revving to the max and spraying the **** out of a h/c impala. for some odd reason, i have a feeling it was something he did, not an actual part failure. but in saying that, i plan on running a double roller with mine for the added peace of mind. i have only heard of a handful of stock setups failing, but the people who state they break never follow up with an explanation of why take it how you want...

 

I am running the LT4 Extreme set and it is a really nice piece, if you look at the stock LT1 versus the upgraded LT4 there is really no comparison. Plus, like others have said, it retains the factory water pump set up eliminating the added expenditure of an electric water pump. If you add everything up, the LT4 set is actually cheaper than a cloyes double roller with EWP, yet still more expensive then stock replacement but I thought it was worth a little extra money for the piece of miind in a cammed LT1. The factory piece on a bone stock motor with 44,000 miles on it had already started to wear rather substantially. I haven't heard of an actual failure except the last post but if you need confirmation of a sloppy timing set on a low mileage motor I can vouch for that. Added spring pressures are going to speed the break down of the factory piece by quite a bit I would imagine.

 

The motor I tore down had 50K miles on it with a cc503 and that chain was trash.