Here's my problem. Will a stock chain be strong enough for a gm847? My non-veneted opti has about 10k miles on it and I don't want to spend the money to convert. I do have an electric water pump so maybe that will take a little stress off of the chain. I also heard that a timing crank gear and chain from a late 80's 305 or 350 is the same as a 94 chain and crank gear, is this true? Because the set for the late 80's is $21 at autozone and I could just buy a new cam gear and save about $30.

 

The GM847 is a high-reving cam. The stock chain isn't meant for that.

 

I have the Lunati timing set with mine. I honestly don't think that it's any better than a stocker. I just plan on changing mine out every 10K or so.

 

To the original poster- Don't half *** your car. You need a tougher timing chain. I was running a HOTcam with an electric waterpump on a new stock chain and it stretched it out noticeably. The extra revs and extra force it will take to spin that 847 cam could end you up in a mess if you use a stock chain.

 

Doubler roller. Can't go wrong. Don't waste your money on the LT4 ED set. Just go electric waterpump and double roller.