454 starter/flywheel ??

[Jason5571]

Hey yall! I have a question for you gurus. I have purchased a 71 longbed and it was fitted with a 454. I don't know how to tell the difference between the trannys. I know modulator valve is located on the side or back to indicate which is which but I don't think that is an issue. Anyway my problem is I bought the truck as is and the guy has put three starters and flywheels on it. They all grind and eat the teeth off the flywheel he "has shimmed the starter every which way it can be shimmed". He did not know what the 454 came out of either for all I know it could be a 396. I can't find the casting #'s on the side of the block to tell me what year it is so I was wondering if they made them the same up to a certain year or did they have alot of change overs? Without the casting #'s I am kinda pissin' in the wind if I just keep throwing parts at it like he did. Any info to head me in a good starting point would be great. I did grind the crap out of it and got it started and that 454 runs soooooooo strong. I don't know why I have stayed with the sb so long. ( other than parts availability reliable it's a chevy etc.)
Thanks alot I have not been on the board in about 8 months because I sold my 69 3 door sub and forgot my old user name. I know I have been rambling but It's 11:16 at night and my house is asleep. Thanks again Jason

[crazy longhorn]

There are 2 options on the starter/flexplate. The 14" diam, 168 tooth flexplte/flywheel takes a staggered pattern on the starter. The smaller12 3/4 " 153 tooth takes a straight across pattern. As far as shimming, you need to slip a 1/8 " rod tween the armature shaft & th OD of the flexplate(not loose, but not tight). if its too tight, you need to use shims under both bolts......too loose, you need to cut the shims in half, & use them under the OUTSIDE bolt only, untill you get the proper clearance. it is not uncommon to see 3 or 4 shims under the outer bolt to get the starter "talking right". after a couple times, you will be able to hear an out of spec starter a block away.......& know what you need to do to straighten it up . Good luck,crazyL

[junkyardjohn]

I GUESS THE FIRST THING TO FIND OUT IS WHAT THE DISPLACEMENT (OR SIZE) & YEAR OF MANUFACTURE THE ENGINE IS. THE FLYWHEEL OR FLEXPLATE IS NOT INTERCHANGABLE BETWEEN A 396 & A 454 AS ONE (396) IS INTERNALLY BALANCED, & THE 454 IS EXTERNALLY BALANCED.
THE DATE CODE, & THE PART # OF THE BLOCK WILL BE ON THE BELLHOUSING BOSS. GO TO MORTEC.COM &THEY WILL TELL YOU WHAT THE BLOCK DISPLACEMENT WAS ORIGINALLY. JOHN

[crazy longhorn]

That is a very good point John internal or external balance.....all of the sb's from 262-350 are internal balance......the BB's from 366-427 are internal balance, & the flexplates or flywheels will swap. The 400 sb, & the 454 BB are external on balance(both different plates), & will have a chunk of weight welded to the flex plate at 1 spot (very noticeable).If somebody has crossed these pcs, you will have a very noticeable engine vibe.I do agree with John , that the best way to run the mess down is by eng numbers! good luck,crazyL

[Jason5571]

Thanks alot. I have the flywheel out and it has the weight on it. It is also a 168 tooth flywheel as well as all the others that he has chewed up. Also all of the starters have straight teeth on them they are not angled. I really don't know why but I think someone has ground the numbers off. It looks like it used to have numbers under the right head but that surface is ground smooth and the same goes for the back on the hump. Thanks a bunch for your input. Jason