Z16 wheel specs
 

A friend of mine is looking for Z16 wheels. Does anybody have the specs on them? It's getting to be swap meet season here. Thank you, Joe

Not likely to find one at a swap meet, but hope springs eternal! The last one I saw for sale was over 20 years ago.

They were only used on Z16's. Don't be fooled by any of the stories that they were used on some sort of station wagon too.

No codes by the valve stem. GM65 stamp between two of the wheel stud holes. Punched hole between two others.

From the front they look just like a 66 Chevelle SS 6-code 14x6 wheel, and have the same offset. (Not like the deeper dish Impala C-code 14x6 wheel, and not like the "in between" Camaro FC-code 14x6 wheel).

But the outer rim is disc brake clearance shaped, not the 66-68 Chevelle drum brake outer rim. And there is only a small, tapered tire bead catch on the rear bead area, not the big hump you see on disc brake rally wheels.

And the center is riveted to the outer rim with counter sink rivets, not welded.

Good luck!!

Jeff, any pictures?

Here's some pics.

Wow...cool!

Thank you for the pictures....Joe

I never knew this about these wheels. If anyone cares, the wheels shown in this thread look alot like the corvette 15 inch wheels found on 57-62 widewheel/big brake cars (100-200 or so made per yr). the rivets are the same inside and out, and those corvette specific wheels had no safety beads. I think there is a safety bead on these Z16 wheels from what I can tell. I am scratching my head why they did the heavy duty rivets. My 65 L8 vette (same engine) does not have riveted wheels, yet this car does? Only difference is weight of the car. A Z16 flying around corners with full passenger load and a trunk full of moonshine maybe needed it. GM could have been hedging their bets in these early days of bigblocks+disc brakes in 65.

I have concluded that the rivets on the Z16 wheel were really just a workaround to make two wheel component pieces work together that were not really designed to be used together.

The different Z16 outer rim (versus a regular drum brake 14x6 outer rim) had to be used in order for a wheel with the Chevelle wheel offset to clear the 11" rear brake drums. A 65-67 Impala C-code 14x6 has the wheel center set deeper in the rim (so the outer rim is further out toward the side of the car), so it cleared the 11" rear brake drums no problem. But If you try to bolt a 66 Chevelle SS wheel (which is the same offset as a Z16 wheel) on a Z16 rear axle, it will not go all the way on before the wheel is wedged onto the brake drum. The "disc brake" style out rim was necessary to provide the additional clearance for the rear drum.

But that outer rim and the regular 65-67 Kelsey Hayes center wheel piece do not have enough contact for a full weld like you find on a regular pre-68 14x6 wheel. Notice in the pics how the "legs" of the center piece protrude out into the air where the outer rim bends outward. There is very little contact patch between the two pieces there. So I think the rivets were the only way to achieve the attachment strength required.

So that fixed the problem at the rear, but the rivets then created another problem at the front. They hit a regular 11" front brake drum before the wheel is all the way on! So that then led to the special Z16 front brake drums, which have an area machined away so that the rivets clear the drum.

Ad hoc engineering at its best!!

I heard stories about the early Mickey Thompson wheels that had the rim and center section riveted together rather than welded. Supposedly the wheels would squeak because the rivets were not as tight as they should have been. They had an unsafe reputation. Hopefully these Z16 wheels had no such issues.

I think by then Kelsey Hayes had the rivet thing down pat. On the corvette front, it was always said checker cab was a place to look for the corvette wide wheels, but I think it was an urban legend thing.

yep, on a low production run, its easier to machine vs a new casting. Cool info on the wheels, I enjoyed. They likely are pricey, the wheels for the corvette (most got tossed) are going still in the 3K ish range. I have not hugged mine in a while ;)