Identifying a DZ302
 

I've mentioned before that my Camaro's 302 lost an oil ring so I was going to take out that engine and build a 383 for it and sell the 302 block. I know the guys personally who built it back in the day and some other info that tells me the engine is an original DZ.
Also as I've stated, they decked the block and removed the engine pad stampings unfortunately. I've tried the police method of using acid to bring the numbers back but the stampings just aren't showing up. They must have either removed a fair amount of material and/or the stampings were a little light like others I've seen online.

So my question: Are there any other ways to evidence that the engine is a DZ302? The casting number is consistent with the 1969 DZ block castings (3970010) and I've read that there may be a way to determine from the crank journals? I'm certainly not experienced in this area so I appreciate any information from you all who know a lot more about this than I do, thanks.

You could post your crank casting number. It should be an 1178. The vin will probably be on the raw casting near the bell housing & oil filter area...Joe

The 302 and 350 blocks are the same. The only difference is that DZ stamped on the pad. Check the VIN above the oil filter to see if it matches your car.

DZ is just a suffix code. I guess that told the assembly line to install a 3" stroke crank (1178) in that particular block.
I think the 010 blocks are suppose to have a little more high nickel content in them??

If the block was originally a DZ-suffix, it would have nodular main caps with '2482' on them, and there would be a 1/4" NPT oil gallery plug just above the timing chain cover from the machining/assembly at Flint. Even with those, that isn't proof of what it was originally assembled as.
The 'high nickel' or 'high tin' content on hi-po blocks is just a myth.

I've had a bunch of 350 blocks with the 2482 bearing caps. If it has something other than the 2482 then that means it isn't a DZ block, but having those caps doesn't mean that it is.

IMO , i don't think its a myth about the harder material content . It clearly states that the new design 1969 engine block has a new stronger construction , tougher cylinder block and extra firm bearing caps in this 1969 gm Camaro brochure. Either way you can draw your own conclusion. Thanks Marc.

no difference in the 302 or the 350 blocks with the 4 bolt mains.
Blocks used were the 386,388,618 and 010.
I believe after January of 1969??? the 010 block was available but not sure on the date.

The 2482 caps were nodular iron where most others were gray iron. I don't know if there were any other differences in the block materials.

The "010" blocks appeared in May of 69.

I posted this reply in a recent thread here:

So what I'm reading here is that there's no real way to definitively tell if it's a real DZ without the pad stamping? That bites.

I went back and looked at it again, and it's probably just my eyes, but it does look like there are some vague stampings coming up. I'm going to double check it with the wife's eyes again tonight since she's got better eyes.

Appreciate the help.

Did you look for the VIN on the side of the block? If your car is a Z28 and the VIN on the block matches your car then it is a DZ block. Easy

The engine isn't original to my car. I will jack up the car this weekend and check on that VIN. With any luck, maybe I can link the engine up with the original car, as I'd absolutely love to do that.

I believe the car that the engine came out of is the 68 Camaro in his signature so it couldn’t be the original to the car.

Jason

OK. Got it.