Timing Chain Replacement

[headrushinVA]

Quick Question. Getting ready to replace the heads and timing belt and was wondering why nobody replaces the timing chain when they replace the timing belt? Looks and operated like a timing chain on a non-OHC car which is normally changed in the 80k to 100k range due to stretching. Why don't these get changed with the belts? Don't they affect timing or do they not stretch and weaken like those of old?

[series8217]

I bought a new one when I did some bottom end work on my ~90,000 miles motor, but only because I drilled out a link pin to get the old chain off. The new chain had as much play in it as the old one.

[headrushinVA]

I have 130k on my motor. I guess I might as well replace the chain then. Any idea what the suggested replacement schedule is on the chain?

Does anyone know if there is an upgrade on these, like on most motors you can go to a double roller or some other performance setup? Maybe different timing options on the gears like timing retard or advance?

[Kohburn]

i wouldn't waist my time on the chain - if you are worried about timing just retime the cams - belt stretch seems to allow 4+cam degrees of redard on the rear exhaust cam - less on the front cams after 60,000 miles.. but by then its time for a belt replacement.

[BlueShift]

It's a pretty involved process to get to the chain compared to the cam belts. I just came inside from removing my chain as I strip my 3.4 down for a rebuild.

You obviously gotta pull the entire front timing cover off, and then you have to either 1) pull both the crank gear and cam gear together, 2.) cut the chain, or 3) pull the intermediate shaft out. I found out that it's simple to pull the intermediate shaft out and the top gear will be freed up - but you can't have the flywheel or flexplate in place if you want to go this route. If you try to pull both gears - you have to use another one of those lovely GM special tools to reinstall the crank gear to it's "specified depth" - which means something they don't specify!

[napatiger]

I just changed the timing chain tensioner because it was pretty worn down.

[headrushinVA]

I am not to worried about getting involved in a big job. But I don't want to do more than needed. So to summarize, there really is no reason to tackle the chain it should be fine. I probably should check the chain tensionor to make sure it is still in good shape and replace as needed.

On a side note I plan on using the GM gasket set for everything, heads, intake, etc. Anyone know of a better kit or is GM the way to go?

[93Oldsdroptop]

If the GM kit has those shitty plastic intake gaskets, I wouldn't use that.

I'd go with Fel-Pro myself.