Question: 454 parts correct ?

[cnyc31976]

Ok I've started to research the part numbers on the engine that came with the car I picked up in Dec.08. Block is matching #'s 454 cast 3999289 = heads are 3999241 = intake 6263753 = the crank has me confused :confused #6223 ? after looking it up, it shows multiple yrs. '66-69 427; '66-70 396; '66-85 366 & 396-402 ? The chart also displayed
"Forged/Hi-Perf" Will all these work together ?

Oh, the cam is a "Crane"
HMV-272-2-NC - 13-18-84


Are there any other numbers on the crank ? (if so, where ?)

Is it possible someone changed out this crank ?

Can I still use this crank ? Should I buy a new one ?

What do I have here ?

Advice welcomed. My intentions for this engines power would be to get it to about 1970's power ratings or so. (car is a'72)

 

[JohnZ]

the crank has me confused :confused #6223 ? after looking it up, it shows multiple yrs. '66-69 427; '66-70 396; '66-85 366 & 396-402 ? The chart also displayed
"Forged/Hi-Perf" Will all these work together ?

Is it possible someone changed out this crank ?

Can I still use this crank ? Should I buy a new one ?

What do I have here ?

Yes, some previous owner swapped out the original 454 crank (4.00" stroke) for that one (3.76" stroke, for 396 and 427), and 427 pistons; mechanically, you now have a 427. To go back to a 454, you'll need a 454 crank and new pistons, and externally-balanced harmonic damper and flywheel (the 396/427 are internally-balanced).

 

[cnyc31976]

Thanks John,
Ok great, what do I do now ? The car has no documentation (yet & most likely never). Can the block handle more HP than what it originally had ?
Should I build a 427 w/454 decals ? I guess I can do what ever ?
Ideas........... ?
Scott

Yes, some previous owner swapped out the original 454 crank (4.00" stroke) for that one (3.76" stroke, for 396 and 427), and 427 pistons; mechanically, you now have a 427. To go back to a 454, you'll need a 454 crank and new pistons, and externally-balanced harmonic damper and flywheel (the 396/427 are internally-balanced).

 

[GerryLP]

So JohnZ,

Is the id 6223 correct?

For my interchange book says 6623 as a forged crank used on 427's, and I could not find the "6223" in that same book (which these books are known to not be 100% correct..:ugh). ...confused

It also warns about a 396 crank identified the same way (6623), but it would not work...

 

[JohnZ]

So JohnZ,

Is the id 6223 correct?

For my interchange book says 6623 as a forged crank used on 427's, and I could not find the "6223" in that same book (which these books are known to not be 100% correct..:ugh). ...confused

I've never heard of a "6623" BB crank.

 

[Hib Halverson]

I'll let the numbers-matching experts on this site discuss the PN or CN issue.

I can tell you that, with some conditions (discussed below) if the engine is now a 427, it will be safe with 454 parts. As "JohnZ" says, if it's an upgrade of the same type (ie: Hi-Perf to Hi-Perf or standard to standard) you'll need the crank, pistons, harmonic damper and flywheel/flexplate out of a '54.

There are two issues to consider:
1) If you want "1970" performance, you'll need to raise the compression somewhat, change to a modern hyd. roller cam and free up the exhaust
2) if you want "1970" performance as in the announced-but-never-released LS7 (465-hp in Corvette) you will need a lot more if the 427 currently has a low-performance block and heads.

Lastly, with "John Z" responding to an earlier post with....

I've never heard of a "6623" BB crank.

...you may want to check your source of information. If you don't have it, I recommend both Colvin's Corvette by the Numbers along with the old Vette Vues Book of Facts series.

Good luck.

 

[GerryLP]

I've never heard of a "6623" BB crank.

Darn some of these books. The errors they contain are counter-productive...:ughw

 

[cnyc31976]

OK thanks guys, I've got some work and decisions to do.... :confused

What would you do ?

 

[TimAT]

I'll toss another thought on the pile. A 454 block has a 4.250 bore from the factory and will easily go .060 over that to 4.310. That and the stock 4.00 stroke crank is 468. Add another .25 to the stroke and get 496. There are rotating assemblies out there- all forged parts with pistons, bearings and rings for $1700.

 

[cnyc31976]

Thanks Tim

I will consider that option too.......
I'm probably a year or two away from driveline work.

Thx,
Scott

Where would I find that assembly for $1700 ? (just curious)

 

[TimAT]

I found one at CNC-Motorsports.com is your resource for High Quality, Hi-Performance auto parts from industry names you trust. Home page all SCAT parts with Mahle forged pistons and they'll do the compression ratio you want. That's just one place, there are a couple of others ou there too.