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  • 1965 - 1973 Classic Mustangs -General/Talk-

I do you identify a 428CJ engine if it's installed?

  • Thread starter Thread starter cvs334
  • Start date Start date Jul 24, 2019
C

cvs334

New Member
Jul 15, 2019
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100 Speedway Road, Roseburg, OR 97451
Jul 24, 2019
#1
  • Jul 24, 2019
  • #1
Ok ... more questions on the Frankencar I am looking at. The person claims it's got a 428CJ. I got a ride and it's not as fast as the 428CJ I remember in '76 ... at the same time I since started racing motorcycles and currently have a Triumph 955i Daytona ... so I may not remember it the same way;-)

The engine cast numbers appear to have a "C" in it, but the rest is nonexistent. Also the C could be grease that I want to look like a C and from other sites the C could be a 390 as well. All the other ways' to ID require a tear down to measure bore, inspect cranks, look at cams and look for the rough C scratched in the clutch area. Is there another way to tell this is not a smaller motor with a 428 valve cover?
 

2Blue2

will be trying this sex one when I can find it
Mod Dude
Mar 5, 2019
4,430
2,893
163
Oahu
Aug 2, 2019
#2
  • Aug 2, 2019
  • #2
Got to have the casting numbers to venture a guess
Being a Franken car I assume it wasn't a CJ unless they can prove it ( how did they know it was in the first place)

If its a 67 or earlier it is probably a passenger car block or a Police Interceptor block.

Head casting number is between the middle spark plugs
If it is a 69 CJ this # will be C8OE 6090N. but this head could still be on 390 block

Useful quote
"Another way to tell if it might be a 428 is to remove one spark plug, take a dowel and measure the stroke of the piston, it should be 3.980", a 390,406, or 427 will have a 3.780" stroke and a 330,352,or 360 will have a 3.500" stroke. Although it doesn't tell for sure about the block it will confirm whether the crank is a 428 stroke. BTW, the 410 had the 428 stroke with the 390 bore, that still would be a desireable motor.."
 
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