Would like opinions on reusing the flex plate from my SB on the new 511 combo?

No ......... I wouldn't .. They are cheap insurance.. Why not buy what you need ..

What style and brand would be best?

I run an SFI B&M full circle unit.........

I was just looking at those. Thanks Dom.

I run the same one as Dom on my 451

looks like there is more than 1 part number on those flex plates. what number should I have for BB 6 bolt with 727?

10230 is the one I have

If they both have the same bolt patterns why not I have reuse stock ones for years, especially the 11 inch big bolt pattern (7/16 converter bolts) M.W. and the stock 8 bolt pattern 426 street Hemi ones

Sure you can if it matches your converter,crank and balance situation. Not enough info to really help.

the old one is off my 4" SB eagle crank and its the 4 leaf style. does look like theres anything wrong with it. Would be going on a molnar 4.25 BB crank. Both cranks are 6 bolt.

On those square flex plates mopar made 2 of
them.. one 6 bolt and one 8 bolt.. I'm talking
the SFI with the bigger bolts for the conv.. but
if you have a BB or a SB the same flex fits.. I
have used mine on about 6 engines over the years
and got the round one for my R3-W-9.... look it
over closely.. if its not cracked.. put it on

I don't like the wimpy star flexplates and cracked a few over the years hence the reason for the B&M full circle plate. Order the one based on the balance weather internal or external...........mines 15+ years old..........

I got this one from a friend that bought it for his 440 and never used it. It was on my SB since 02. It might be time to retire it.

Dominic, Thumperdart, is correct about the light duty stock ones cracking, I've seen several like that
I've never heard or saw a stock full size solid Mopar flex plate break or crack
Mopar used the exact same cores for their SFI plates they sold and added more money onto them for that SFI tag
I have never seen or heard of any NHRA or track tech at a drag race crawl under the car to look at the SFI tags on the tranny , flex plate or flywheel shield

prw any good

I have no idea on them, I would go to my local Dodge or Chrysler dealer and see how much a new HD one is, non SFI Mopar made four solid HD ones with the 7/16 converter bolts, 6 and 8 bolt non SFI for all the stock motors that came with the converters with the 7/16 bolts and the other two where the same ones with SFI stickers on them
They also made two different sizes of the standard light duty OEM ones for both 11 and 12 inch converters with the 5/16 converter bolts, they where for six bolt crankshaft flanges only though
If yours is in decent shape and reusable I would probably reuse it

Mine is the 4 leaf style. Would like to up grade to the round style. Thanks cab

The PRW are great for the cost. Some of the diesel guys are running 1000hp thru the platinum series ones and I have never head of a failure.

Damon

Your making the correct choice, don't take any chances on race parts
I have seen racer drill out the stock leaf style 5/16 holes to 7/16 bolt sizes and then had them fail completely at the races