How do I know it's a 383

[565bbchevy]

I Googled it. Is this a 400 sb crank?
View attachment 108041

It is to show rear main differences, newer 1 piece versus early 2 piece rear main seal

 

[Yav8]

The stroker kits can be had for both the one piece and two piece seal motors. Any motor after 1986 will be a one pieces seal motor and a right hand dip stick.

 

[pagrunt]

I Googled it. Is this a 400 sb crank?
View attachment 108041

As noted one being a one piece seal (left one, all '86 up production blocks), the other the two piece seal (right one, pre '86 production, that is the 350 flange.)

 

[Smack-it]

Just my 2 cents.....no paperwork is a stock 350. If it's a true 383 he will find a way to prove it