Can anyone tell me what year motor I have??????

I am trying to put in a what I thought to be 80's 302 motor with my 71 c-4 tranny. I went to the local speed shop and they gave me a 157 tooth 50 oz flywheel. After I got it all in and fired it up it vibrates like crazy. So what is my problem. The flywheel I pulled off said 75 351M I guess that should have told me something. Are there any casting numbers that will tell me what year motor I have. Well any help will be appreciated.

thanks William

 

casting number

If I remember right, It's on the passenger side of the block just over the oil pan toward the back.
the first two digits of the number are what you need to know the year.
the first digit is the decade and the second the year.
ex. c8 = 1968, d7 = 1977
give me the casting number and I'll look it up for you.

-Ray

 

castings

alright I went and pulled the casting numbers and they are
D4DE 8015 BA and below it there is these screwed into the block 4L26 this is not a stock motor and I don't know if anything could have been done to make it need a different flywheel. It has a cam and a 4 barrel.

thanks for any help
William

also the flywheel I pulled has 75 ford 351 M written on it with a paint pen

 

casting number

okay.
That is a 1974 302 block and could possibly be an 8.229 deck height unit rather than the normal 8.206. Won't matter unless you are rebuilding it or replacing valvetrain parts.
are you sure your balancer and your flexplate match each other?
I don't remember when exactly they changed from 28 to 50oz imbalance but I do know it was right around then.
FYI- the casting number you gave me wasn't entirely accurate.
D4DE 8015 BA should be:
D4DE 6015 BA
the middle number indicates the type of part, 6015 being the number for a block.
My advice if you can, would be to replace the damper and flexplate with new units to be sure they match.
hope this helps.
-Ray

 

Well, sounds like you need to switch back to the 28 oz balance on your flexplate since that is a 74 302. The engine balancing weights switched in the early 80s.
-Corbin

 

tranny's

well I pulled the tranny back out in all of about 35 minutes. That's what you get when you do it three times in the past week. My 164 tooth flywheel has a smaller weight and the 157 tooth that I bought has a weight about twice the size of the 164 tooth. I don't know if this will help or not but I put both flywheels on a scale and the 157 tooth weighed just little more than the 164. the 157 tooth weighed about 6 lbs and the 164 weighed about 5 3/4 lbs.

any help will be greatly appreciated

thanks WIlliam

 

28oz to 50oz switch

You are right Corbin.
I remember now, 1982 wasn't it?

 

Yeah, I believe it was 82.

William, you need a 157 tooth 28oz balance flexplate for your 74 302/C4 combo. The only thing you need to change is the balance of the flexplate you have. You can either have it rebalanced or, get another one. The 28 oz 157 tooth flexplate will be easier to find than the 50oz you have. Good luck.
-Corbin

 

Re: tranny's

WOW, 35 minutes? I think I remember changing a c4 at the races once in just over 30, but that was pushing it. Can I give you a call when I need someone to change my powerglide? Just kidding . Yes, you'll need a 157 tooth 28 OZ balance flexplate. A good clue to this would be the old flywheel that you pulled off...the 351M's were all 28 OZ balance and 164 tooth. Good luck

 

tranny

yeah it would have been a good clue ,but the kid I bought the motor off of said it was an 80's so I took his word for it and went on. Where do you live at in Arkansas ?? ever go to centerville??

thanks for the help
William