What is meaning behind Z28? I have heard 2 doors 8 cylinders and that seems to work for Z24 Cavalier and Z26 Beretta BUT what about Z71 Silverado and Z66 Avalanche?

 

Simple...with the 1st Gen Camaro, "Z27" was already taken!
"Z28" was an RPO, (Regular Production Options) code.
RPO Z27 was the SS model, so RPO Z28 would have been a natural "next in line" choice.
No secret mystery to how the first gen Camaro got the Z/28 name. Up until the 1974 model, Z28 was still an RPO code. On later models it's a package name, not an RPO.
I think Chevy just likes to capitalize on the performance image that's been associated with the "Z" name. And either it's all an eery coincidence (not), or the Z24 Crapalier is called that for having a 2.4 engine, the Z26 Beretta for having a 2.6, the Z71 Silverado for having a 7.1 Duramax engine, and the Z66 Avalanche for having a 6.6L Duramax engine.

 

I haven't come across a 7.1 Factory Duramax. I know you can stroke them to that though..

Z71 is a Worthless "Offroad" Package.

 

The Cavalier Z24 , for the first few years, came with a 2.8 V6. So that blows that theory..lol

 

Gm made a 2.6? He is correct on the Z28 origin tho. It was the code for the package. It was luck I guess. The 67 did not even have any external badges. The 302 did all the talking it didn't need no sticking badges.

 

Badges? Who needs freaking BADGES!