An associate of mine has a 2000 5.7 Vortec in a 3500 motor home. (Yes, it seems the Gen 1 SBC was carried over for a few years for these types of applications.) This engine has a rear mounted distributor and it also has a crank position sensor.
It would seem that the gear sets are different for this engine when compared to a run-of-the-mill Gen 1 SBC. I'm told that the crank gear has carved it's way into the crank sensor.
I've read somewhere that there are different widths of timing gears.
Anyone with any insight?

 

You gotta use a single-roller set intended for the Vortec, it costs more and isn't the best, but the pcm needs that reluctor wheel, and it only works with the single-roller set and the Vortec timing cover. Or convert it to TPI or carburetion.
The genuine GM timing chains do stretch, not as bad as before, but if you can find a better aftermarket set that isn't Chinese, that'd be the way to go.

 

I haven't seen what this guy is up against but it sounds like a too wide crank gear, in combination with the reluctor wheel, has things misaligned enough to mangle the sensor. Being a carb guy (and subsequent electronic add on's unneeded) I've never experienced this before.
I'll talk to him and see what he picked up for a timing set.

 

I used a Cloyes C-3017 timing set on the last Vortec I put together with a crank sensor. I don't know about in Canada, but in the U.S., NAPA, O'Reilly, & Car Quest are supplied by Cloyes. I got mine at the local NAPA store. I don't remember the price, but it was not expensive; I think $30-$40.

 

I see some sets are advertised with a specific "x" width. I'n assuming that's the crank gear that's measured. From the sounds of it, buddy boy installed a standard set in his Vortec block (which besides a small cam upgrade is all stock).
I'll measure a standard set here at the shop and compare it to the catalogue spec for the Vortec.