289 or 302?

[KaraKedi]

Hello,
I bought a 65 Mustang one year ago.
I heard form old engine man, my engine should be 302.
According to code, engine is 289 A code.
How can i check it's 289 or 302?
How can i understand, are there any engine number or physical difference between 289 and 302
Regards

 

[silverbluebp]

It should be a 289 unless someone replaced it in it's history. The block is stamped with the date on the underside rear, by the starter IIRC. You could also pull the valve covers and see the date stamp of the heads.

 

[rbohm]

the stock V8 engine in mustangs up to 1968 will be the 289. personally i wouldnt worry about which engine you have since just about everything interchanges between the two engines. the differences are slight, and the 302 puts out a bit more low end torque, and the 289 revs a bit higher. unless you are building a perfect restoration, go with what you have.

 

[izzy jr]

It should be a 289 unless someone replaced it in it's history. The block is stamped with the date on the underside rear, by the starter IIRC. You could also pull the valve covers and see the date stamp of the heads.

I wouldn't go solely of the date stamp on the heads cause someone could've swapped out the heads. When I bought my car I was told it had a 68 302 w/ original rebuilt c4, when doing a tune up to see if I could get it to run I discovered it had 70 351w heads when I was swapping plugs.

 

[D.Hearne]

I wouldn't go solely of the date stamp on the heads cause someone could've swapped out the heads. When I bought my car I was told it had a 68 302 w/ original rebuilt c4, when doing a tune up to see if I could get it to run I discovered it had 70 351w heads when I was swapping plugs.

You can't go by spark plugs either in your case, both the heads you listed used the same plugs.

 

[D.Hearne]

The only way to tell between a 289 and 302 at this point in time is by looking at the crankshaft numbers. You could have a 289 crank in a 302 block and still have a 289. Or a 302 crank in a 289 block and still have a 302. And as rbohm stated, there's no need to even worry about it, the power output numbers are so close anyway.

 

[izzy jr]

You can't go by spark plugs either in your case, both the heads you listed used the same plugs.

HUh? that's weird then cause none of the plugs listed for a 68 302 were the same as the ones listed for the 70 351w heads. I had to take a plug from each head with me and trace the numbers on it as to which eng's it was made for to figure out what plug I had and to be safe I had a local eng builder I know come look at the car to tell me what plugs to get.

Either way my point was that the markings on the heads may not correctly identify what eng you have. That being said there's no telling what the internals of my eng really are, I haven't done a compression test on it or pulled it apart to look at any of it yet.

 

[D.Hearne]

The 69-70 Windors plugs are fully interchangable with a 68 302's plugs. The stock plug numbers may be diffferent, but they're the same threads for the hole.

 

[htwheelz67]

if its a 74 or earlier it takes the big plugs 3/16, 75 and later uses 5/8. The only difference would be heat range.

Your old engine man must be a chevy guy or a really bad alcoholic or has alhiemers as ford never made a 302 until mid 68........in a mustang it was only a "230hp 4 bbl"( old hp rating) in 68.

 

[D.Hearne]

There was a 2 bbl 302 in 68 as well as the 4 bbl model.