Comp Cams is telling me that my stock L98 timing chain has advance ground into it, and that dot to dot isn't really a true zero degree install.

I find that a little odd, but it doesn't seem like it would be impossible. I don't have a degree wheel, so I don't have a way to verify one way or the other. Has anyone else ever tested a stock timing set?

We may be on different pages but when I degreed my LT4 hotcam it was about 1 degree advanced. That is the cam was ground that way not the chain or sprockets.

So what was your final intake centerline?

I am sorry but I did not see your posted question. But at any rate, I don't remember. It was over a year ago.

Also if what I'm thinking is what you ask. You can't degree it with the stock chain set up because you need an indexing sprocket. One jump of the chain is too much change in timing. At one time you could get offset keyways though but they are prone to shear.

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No, degreeing the cam is just measuring it to see if it matches the cam card. If you end up needing to adjust it, then you do need an adjustable timing gear set.

I bought a Comp Cam for my 91. I bought Cloyes double roller replacement timing set from a local auto parts store. Comp Cams is telling me that the stock timing gears have retard built into them and the dot to dot is not actually zero. I don't have any way of checking that because I don't have a degree wheel or dial indicator.

If I could actually measure the intake lobe centerline, with the stock timing set, then I would know exactly what the deal was. Like I said though, I don't have the tools.

I ordered a wheel, dial indicator, magnetic base, and piston stop from Summit earlier today. Once all that shows up, I'll measure everything and post back.

Hopefully, Comp Cams is wrong and I can use the stock replacement timing set. If they are right, then I'll have to buy a timing set from an after market company. But I won't know until I check it; or if someone posts between now and then with a definitive answer.

I don't doubt what Comp told you is true except they were talking about the crank gear. Back in the 70s a lot of full size Chevy sedans came with a timing gear that was retarded. I want to say 2 degrees but don't quote me. This was done strictly for mileage because we were in a supposed fuel shortage. One of the popular mods was to remove the gear, turn it over, grind a bevel on it and reinstall. This was well published mod at the time. The replacement timing sets at the time were not retarded. Later! Frank

My tools should arrive today in the mail. I should know by tonight what the deal is.

That's interesting about the older cars having 2 degrees retard built into the crank gear.