I just mated my rebuilt 400 to the newly rebuilt C6. There is also a new flexplate, and a new converter. I am having an issue with my converter clearances. The engine and trans fit together easy, but once the bell housing bolts are snugged up there is no play in the converter.

The flexplate I have is a EnginePro 32-201, which is the same part type as a Pioneer FRA-201. I was thinking of upgrading to better flexplate to see if I might get better clearances. I see that the aftermarket performance flexplates, like those made by TCI, basically list all small block Fords (289,302,351W/C/M, 400) with the same flexplate. While you look at the OEM replacement parts, and the 351C/W has a different flexplate, FRA202 vs the 351M/400 which uses FRA201. So there has to be some difference, which I am assuming is the offset. B&M shows that the converter to bell housing for a C6 clearance for engines under 360 CID is less than those over 360. So I am assuming this is the reason why saw a 351C uses a different flex than a 400 Ford, when all else is equal?

Has anyone here run a high performance aftermarket flexplate on a 351M or 400? How was it for clearance vs a stock style unit?

 

You should be absolutely sure the converter is seated fully. If not you can do a lot of damage. There are two sizes of C6 bell housings, large and small. The 400 uses the large and I assume the flex plates would match.

 

D1AZ-6375-A .. C6 Flexplate - 164T / Obsolete

1971/79 400 Passenger Cars; 1975/79 351M Passenger Cars; 1977/79 F100/350 351M/400; 1978/82 Bronco 351M/400; 1980/82 E150/350 & F150/350 351M/400.

 

I am pretty sure the torque converter is fully seated. I tired it many times, and I cannot get it to seat any further. I pulled it out and was able to see that it is engaging the front pump drive. I turned the converter and then removed and checked the pump drive and it also turned.

The problem is I am only getting about .95" from the bell housing to the stud bosses. When the bellhousing bolts loose, I can wiggle the converter studs. When the bellhousing bolts are tightened I lose all play at the converter. It's too tight.

The aftermarket replacement part flexplate I have does cross reference the one Number Dummy provided, so I know its correct. I am just wondering if the aftermarket high performance flexplate might offer more space since it seems to cover all small block for families and even both C4 and C6 transmissions.. The replacement parts and Ford factory parts are engine family specific and transmission specific.

I was just hoping someone here had used a hi-po aftermarket flex on a 400 with a C6 before I spent the money. Just wondering how it worked and if it offered more clearance. I am looking at a TCI 529628 specifically. It shows on summits page that it fits Ford 289,302, 351W/C/M and 400. It has a 28 oz imbalance, and a 164 tooth gear.

https://www.summitracing.com/int/par...view/make/ford

 

When it's tight it's locked to the crankshaft.

 

I am not sure what you mean? I am installing the converter on the trans before I connect the two, so the crankshaft isn't in play yet?

 

I'm a little confused too. If the converter wont turn before you put it to the engine there is a problem I think.. After you bolt it to the enigne/flexplate it will be hard to turn because you have to turn the engine over. It still sound like it's not seated. I believe you should hear two distinct cluncks as you turn it and push it in.

 

I am pretty sure the converter is seated. I got the clunks and it sits far back in the bellhousing. And like I said it also seems to be turning the transmission pump drive.

What I mean is I was always taught that when the engine and trans our mated, you should still be able to grab hold of one of the torque converter studs and wiggle it because there needs to be some play. Tight damages the trans pump. I can wiggle the studs when the engine and trans are loosely mated. Once I snug the torque converter bolts it gets tight and I cannot wiggle the studs. Everything gets right. I can turn over the motor with a breaker bar with ease.

My problem is I think I don't have enough space between the converter and the flexplate. That's why I was thinking the offset of my flexplate was wrong I was hoping a hi-po plate would give me a bit more clearance between the flex and the converter.

 

Whats the brand and part #?

 

https://www.ebay.com/itm/New-OEM-197...-/152987137297

There looks to be an new old stock.Says they ship worldwide,72ford.

 

Did you test fit the converter into the cranks pilot ? That's always the first thing I do when I get a new one out of it's box.

 

The flexplate I have is a EnginePro 32-201, which is the same part type as a Pioneer FRA-201. Thanks for the link with the NOS flexplate. I may go that route.
In the mean time I ended up finding a C6 flexplate locally. It's a Ford Part. So I will pull it apart and compare it to the aftermarket flexplate.

I also did try fitting the torque converter to the engine and flex. It fits fine, no issues. I just think the issue is either my flexplate is out of spec or my torque converter isn't sitting all the way in the transmission pump drive.

 

I figured out the problem. The pump gear was installed backwards, which wasn't allowing the converter to seat as deep as it should. So no need to buy a new flexplate. Thanks for the help.