427/428 crankshaft ?

[otto]

Hi, cleaning up the cobra i bought a few weeks ago and noticed that the motor has the cast counter weight behind the balancer, would this indicate the cranshaft in this motor is a 428 flavor or could it still be a 427 crank with maybe the scj rod package , any info or thoughts would be great
thanks Bob

[Rick Parker]

428, My understanding is that the 427's were internally balanced.

[FFR428]

428 SCJ crank spacer to be more specific. Stock those used the LeMans rods and the 1UA SCJ crankshaft. See component ID section at Mustang 428 Cobra Jet Registry

[lovehamr]

Are you sure it's a 427?

[FWB]

Bob,
it is possible to have the 428 crank in a 427 block it was how to make a stroker before the aftermarket cranks were avail. if the block is a crossbolted 427 then it would have the 428 crank, balancer, flywheel\flexplate, 428 rods.
the pistons were custom specifically for that crank-bore combo, 454 cubic inches could easily be achieved with factory parts.
but on the other hand it could be just a 428.......you will need to get some block casting numbers to be sure and check for crossbolts on the block skirt.


fred

[Dumpling]

The only way to be certain of anything after almost 50 years is to measure the bore and stroke.

Measuring the bore might present a problem without removing the heads, but you should be able to measure the stroke through the sparkplug holes if it really really concerns you.

If it's running and performing to your satisfaction, I 'd leave it alone and not worry about it until something breaks and needs fixing/replacing.

What were you told the displacement was when you bought it? If you convert to efi and need to set parameters that might be an important number to know.

[otto]

Hi, took a peek under the car tonight and spotted the crossbolts at the base of the block and the 3 pipe plugs on the left bank with a slight bulge so i would say i have 428 crank in the side oiler block unless i am missing something.
thanks for all the help
regards Bob

[FFR428]

Nevermind......misread your post that you saw the pipe plugs in the bulge. Yep would be a S/O.

Cool find and enjoy the new ride!