Mustang EFI Conversion on '74 - Torque Converter Compatibility Question

[rean1mator]

Hi All,
I'm currently in the process of getting an EFI/Mustang 5.0 conversion on my '74 Bronco and have a question regarding the existing torque converter not fitting/matching up to the automatic transmission.

My mechanic said he dropped in the engine and could not get it to fit and had to pull the engine back out. The reasoning he gave me was that it was not a stock torque converter but an afermarket one.

My question is tho'. If it fit with the old 302 engine, why wouldn't it fit with the new engine regardless if it is an aftermarket converter or not. He ended up having to order a new one from Wild Horses 4x4 after consulting with them.

I'm just trying to find the logic in his explanation which is not adding up.
He later then said that the last conversion he did was on a manual transmission bronco which worked.

What am I missing?

 

[rguest3]

If it's the same transmission and same torque convertor it should fit.

302 engine - 28oz. Flexplate
86-87+ 5.0L - 50oz. Flexplate

The difference is the Mustang, 50oz flex plate that may not be compatible. Do the convertor bolts line up with the required, Mustang 50oz flexplate?

 

[igottastanger]

Dont everyone jump on me for this but i have converted from standard to automatic before and had the same problem. I left the pilot bearing in the block so nothing matched up.

 

[Quick & Dirty]

Some Bronco's came with a converter that had a 10.5" bolt pattern. The 164 tooth 10.5" bolt circle flexplates were always rare, and are now a special order item. I don't think a 50 oz-in version was ever a factory part.

The 10.5" pattern converter is normally used on the 157 tooth flexplates, for small bell housing C4's. Some were used in the big bell housing transmissions in muscle cars and Broncos for a little higher stall speed.