SBF Flexplate differences between C4 and C6?

[reynard101]

Are there any difference between the flexplate for a small block 302 or 351W for the C4 versus C6? I know there is a 157, 164 tooth count AND also 28 oz and 50 oz balance differences AND the torque converter bolt pattern sizes of 11.5 inch/10.5 inch. I can't find any other documented differences. Are they the same? Is there a different depth for each transmission or any other physical dimensions that vary?

 

[Broncobowsher]

AOD, C4, 4R70W use one offset
C6 uses another
No idea what a FMX uses

Don't know measureable differences, but have been taught there is a difference and been around people who can just look at them and tell.

 

[reynard101]

This is more of a rhetorical question: How come none of the parts suppliers list which transmission application the flexplates are for? Or am I just missing this info?

 

[Viperwolf1]

This is more of a rhetorical question: How come none of the parts suppliers list which transmission application the flexplates are for? Or am I just missing this info?

Try here: http://www.bulkpart.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=2&Category_Code=FLYFORD

14.23" diameter is 164 tooth.

 

[red hot71]

Side by side the 351 flywheel has more offset,1/4-3/8 if I remember right.

 

[Broncobowsher]

Side by side the 351 flywheel has more offset,1/4-3/8 if I remember right.

351 is the same offset as 302.
What you are probably looking at is C4 to C6 variation.

 

[reynard101]

Thanks guys, all good info. I guess there is a physical difference. I just wish I knew how to measure for this difference.

 

[mattt]

I will try to dig up some pics that show the difference. Once you spot the difference it's very easy to see any time you look at a flexplate. Best way to explain it is where the plate meets the ring gear, the C4 plate steps down & on the C6 version it bubbles up a tad. Pictures are worth 1000 words here.

 

[mattt]

The 1000 words... The plate on the left is the C4/AOD/4R70W offset. The plate on the right is C6/E4OD offset. If you look right where the ring gear meets the plate, you'll see how the C4 plate steps down(towards the crank), and the C6 plate kinda steps back up towards the trans.

 

[reynard101]

Thanks Matt. That helps clear it up.