Hey everyone I recently bought a 1987 IROC-Z with a VIN number showing it came with a 350 TPI which the PO confirmed but after comparing some pictures of other TPI's I've noticed the motor in my car seems to have different valve covers from the TPI's in all the pictures I've seen. It also has a brown sticker on one of the valve covers saying "this part has been specifically designed for off highway application only. Since the installation of this part may effect your vehicles emission control performance..." It goes on to say a few other things but would this mean it simply has aftermarket valve covers or is this indicative of a crate motor that has the TPI heads on it? Here are some pictures:

 

Looks like a bone stock TPI SBC with some aftermarket (maybe the dealer sold 'em too) valve covers. No biggie - Pull the sticker if you're worried about emissions - A valve cover won't affect any of that.

 

Why would they put that sticker on there if it doesn't effect emissions at all? GM wouldn't just slap that on every aftermarket part. There are so many weird things to be found when you buy an old car, I actually found an old pair of mens underwear stuffed under the passenger seat lol. Who does that?

 

His Girlfriend lol!!

Looks like just a different set of valve covers to me as well.

 

If your doubt full about whether its the original engine or not there is a partial vin number stamped into the block on the passenger side right behind your alternator. There is a flat spot on the block right in front of the head. Unless its been painted over you should be able to clean it up and read it. Follow this link and there is a picture in the second post.
https://www.thirdgen.org/forums/engi...-question.html

 

They may not be made for a PCV system specifically. I can see the PCV is in tact tho so as said befor, just the sticker off. And if you have time clean them up while your'er in there. Those chrome valve covers look really good IMO

 

get the id number off the back of the block and google it also the number on the front below the passenger side head these numbers should tell you what you need to know. also see if your build sheet is still in the car usually under the drivers seat, becareful it may fall apart.

 

That sticker was put on the valve cavers of the ZZ1, ZZ2, ZZ3, ZZ4 crate motors for street rods. If the motor has aluminum heads (L98) I would say its the case.