Someone went dredging for threads. Unfortunately this one should have stayed at the bottom. There is some bad info up there.
Windsor pattern transmissions do fit the 300/302/351w and C among others.

 

This is for reference for all SIX-bolt transmissions and engines. I'm not going to get into the early FIVE-bolt ones.


The 289, 302, 351W, and 351C, 300-I6 all used the same bell-housing bolt pattern. These engines also have the same bolt pattern on the crank for flex/flywheels.

The 302 actually changed from a 28 oz imbalance to a 50 oz imbalance in mid '81. (I've pulled 1981 engines that have had both weights already).

The 351W always had the 28 oz imbalance, that never changed.

If You want to use a 351W in place of the 302, it WILL bolt up. You will need a flexplate for the 351 or early 302 though. If you use the wrong balance, you WILL tear up your main bearings in a hurry.

If you want to use the 351W with an AOD, you will need a flexplate (if buying a new one) from Pioneer with the part # FRA-205. Do NOT go by the computer or book at the parts store as they have the wrong number listed for them. This flexplate is listed correctly for a 1990 Crown Vic with a 351 and AOD. That one will work correctly. The one they list for the trucks have the wrong backspacing. You will know right away as the trans will not seat to the engine correctly. If you force it and run it like that, prepare to trash the trans pump. You can get the correct flexplate from Autozone or O'reillys for about $50.

I realize this is an old thread, but wanted to help clear things up.

 

Yep, ive seen lots of people on the whole 28 oz vs 50 oz. Ive had people tell me that 82 302s were 28 oz when in fact 82 was the first year for all 302s to have a 50 oz imbalance.


That's the problem is some times false information get spread and taken as fact.

 

Another thread hunt revealed this one:

https://www.ford-trucks.com/forums/4...confusion.html