Flexplate question A 904 lockup 1980

I've got a Cordoba, 1980. It's got a 318 and a lockup trans I assume based on a 904.
Does anybody know with certainty which flexplate it would have? 10" bolt circle or 11" bolt circle? I could pull the cover and look but can't get to the car until next week. If it's one or the other for sure I could order a flexplate..... lol
If anybody knows for sure let me know, if I have to wait until Saturday to look for a D or an O I'm ok with that too I guess lol
THANKS!

the common small 904 plate I would assume. whats wrong with this one?

IIRC 904s most times use the smaller one but can have either.

if a 727 it could have either.

flex plates are same for /6 SB BB engines so match up TC size.

IIRC under the cover on a 904 you can look at ring gear on TC for size.

10" has a tall ring gear 11" has a short ring gear

I have a satck of both sizes if you want a stock flex plate correct size.

if you go B&M it has both size covered and you just pick internal or external balance.

speaking of 80 dobas it could have either 904 727 so ID the trans pan shape for sure.

2v or 4v? floor shift?

I want to swap in a 360 and don't want to disturb the converter. It's a lockup trans and the 318 internally balanced. I thought I would grab a B&M flexplate that eliminates the weights.

A 1980 Cordoba could have a 727?? Never heard of that!!!
I always thought 1980 Cordoba 318s were alllll 2 barrels, but for whatever reason I'm pretty sure the 4 barrel on mine is stock. Weird?

Floor shift

Thanks guys!

It's more then likely a 904.
Get ready to do a trans swap because the 360 will kill it at some point. But it's fun while it lasts.

Yes I would look for a 10239 B&M new or used.

lol
It's a 904 based lockup trans. They last behind healthy 360s. I know, I ran one for years and years back in the 1990s.

No idea where you get your info from.

That's the dual pattern right? I assume the larger flexplate will fit in a sbm bellhousing regardless of lockup or not? I think that's the better way to go actually. Thanks RR.

Heck, when I swapped a 360 into my 72 Swinger the donor was a 79 Cordoba and the trans was an A999, original to the Doba.

I think my original Cordoba I had to buy a converter with a higher stall at one point, and was told the trans was referred to as a hydraulic lockup A999. Not sure if that was accurate or not but the converter worked!!! lol

I think lockup based A904s came stock behind all the 360 J body Cordobas and Miradas. Just not sure if A999 is proper designation

A904 - /6
A998 - 318
A999 - 360

A727 - 340

So is the lockup trans in my 318 J body an A998? What's the difference to an A999 I wonder?
Thanks SuperCuda! I always wondered.....

I forget the details, but basically more beef. I want to say clutches and plates but it's been a while.

From what I can see they also were available with a wide ratio which makes sense, cause mine accelerates wayyyyyy better than a 318 Cordoba should and still goes on the highway ok. My buddies thought gears but I kept saying how? It cruises at 85 mph easily.....

Yes it is a dual pattern & I have used em several times with no issues. I didn't get the larger plate question.

The larger 10239 flexplate. The 10236 flexplate is 10" diameter converter bolts only and slightly smaller outside diameter than the 10239 I'm sure they should both fit....

In my experience, you are correct. I put one behind a 5.2L Magnum. The rebuild kit came shy of the number of frictions and steel plates that I pulled out of the clutch pack. Had to buy extra pieces to fill the pack. I was using an A998 Transgo kit.
Craig