Hey guys, was hoping you could help me out in figuring out what engine I have.

So, here's the story.

A while back I bought a 1972 Chevelle. The car came with and engine and transmission, but they were not in the car. I was told that the engine was a 400 small block.

So I brought it home and stripped it down, and right away I realized that this was not a 400 small block. For a long time I thought this was a 350, but I started searching some numbers recently.

I don't have many specialized tools such as a mic, but with a caliper I found that the bore is exactly 4 inches. I have not been able to check the stroke yet.

The numbers on this block read 3970010, which from what I see could either be a 302, or a 350. But from what I have read, the 350 of that number would have been a 4 bolt main, whereas this engine is only a 2 bolt. So, that leads me to believe this is a 1967 Chevy 302. Is there anything else I could check other than the stroke that would tell me for sure?

Also, I have heard people saying something about a DZ block, what does this mean and where can I find out if I have one?

And also the heads on this engine have an elongated triangle marking on them, and read 3947041. I would assume these are 400 head, is that correct?

Any help is extremely appreciated. Thank you for taking the time to read this, and sorry about any grammar or spelling issues, I am fairly tired right now.

 

A 3970010 casting could be a 302, 327, or a 350. If it's a 350, it could be either a 2 or 4 bolt main. Measure the stroke, that's the only surefire way to check.

 

Thanks. The article I am reading lists them only as the 302 or 350 engine.

302 (1967-1969 Z28 Camaro)
350 (1968-1973 High performance trucks) (4-bolt mains)

 

The suffix code on the front pad will tell you what it is: http://www.chevy-camaro.com/chevy-ca...oding-help.asp

 

 

yes. I believe the engine code number should end with DZ or MO if it's a 302.

 

dz for 69 and mo for 68

 

DZ is late 1968 and all of 1969. MO is 1967-68.
Cross-referencing the casting number and date code on back of block, and the suffix code on the front passenger side pad will determine what it is.