1965 421..
 

Hi everyone... I found off craigslist , this 1965 (421 c.i.d.) #9778791 356HP - Code YJ, 93 heads, When I got to guys garage it was stashed under his work bench coverd in 25yr old oil and dirt and grease ..... I was the first person to take a dirty rag and clean the suffix code YJ and the casting date D-14-5, yet I still didn't know what this motor was.... So I call my Dad and we had quick beer and we pick this engine with in an hour... It was great pickin and having beer with my Pop he's 80yrs..... Can anyone tell me about this motor..... I would post pics , but I don't how to upload from my picture files on my computer to this site , cause when I click the picture icon on this post, a url box pops out! can someone help me !!! thanx Jim

You pretty much have all the info on it, except what car it came out of.

Only things I can tell you from your provided info is that:

"YJ" - Automatic

And normally this engine would have came with #77 heads which are 1965 High performance heads used on 389 blocks in GTO's or 421 HO blocks.

#093 heads were 1966 heads used on 389 blocks in GTO's or 421 HO blocks.

I have heard that late 1965 389 or 421 blocks could have gotten #093 from the factory instead of the #77 heads.

Date code for the heads are located on the outside just below the valve cover mounting pad between exhaust ports. I would think if heads match the block, the head date code should be relatively close to the block date. If the head date code is far into 1966 year than maybe the original #77 heads were replaced at sometime in its life with the #093.

Should have 4 bolt main caps, 4 inch stroke crank, 4.09 bore and 4 bbl carb, and what is called a transfer lug (protruding pyramid cast into the top rear of block) on the passenger side of the distributor pad. You will see it, sticks up about 2 inches. 389's did not have this in that year.

I am sure more people will chime in.

Hope this answers some of your questions.

Mark

65 YJ 356 hp auto tri-power 10.75 comp..77 heads and of course TRI POWER

I looked at the heads again , and found the # 77 on the coner of each side.... Thanx.. Jim

My bad, YJ is the tri-power motor, must have glimpsed at the YH on the chart.

http://www.ronspontiacpage.com/reference-pages/1965.htm

Mark

I would post pics , but I don't how to upload from my picture files on my computer to this site , cause when I click the picture icon on this post, a url box pops out! can someone help me !!! thanx Jim

email me the pix i will host them for ya..

Click on the paper clip which is attachments in the advanced quick reply screen to load pics.

My 66 ...

Thank you ( ITSBACK) ......

1965 421 pics
 

1965 421 pics

Hot young chick named Maria , she drinking beer and having fun, next my 66 at the Primer Nationals, Ventura Ca..9-3-11

Not sure what I like better, Maria or the car, they both look great. What kind of primer is that?

Its a base black with a flat clear...
 

Its a base black with a flat clear....My 66 before paint...

Nice.... both Maria and the 66. :D

BTW... what did you do with the Cragars?

Still got them with Goodyear Slicks....