Is it OK to use 1" long bolts for the flexplate on small block Ford?

Guys,

I'm just getting ready to drop my 5.0 back in the frame (4th time now, I think...ugh). Anyway, I noticed that the flexplate bolts were 1" long. They seem a bit too long, but they are the factory bolts I removed from a 1996 F150 that had the 5.0/E4OD.

I tried to measure the thickness of the flange on the crank where the flywheel/flexplate mounts with a piece of wire, and it appears to be 0.900" thick, and the flexplate is approx 0.095" thick, so I assume the 1" bolts would be OK (they actually measure out at 1.043" long). I guess worst case scenario is that the tips of the bolts would be 0.040" proud in the back of that flange. Does it matter?

I thought flexplate bolts were 3/4" and flywheel bolts were 1", but these were the factory bolts from a 5.0 with E4OD that from all appearances looked to be original and untouched.

I'll see what I can find in the catalog...

The MPC shows that all automatic transmissions hooked to a 302 out through 1989, which is as far as the catalog goes, used a D2AZ 6379-B which is 7/16"-20 x 23/32".

Gary Lewis wrote

The MPC shows that all automatic transmissions hooked to a 302 out through 1989, which is as far as the catalog goes, used a D2AZ 6379-B which is 7/16"-20 x 23/32".

Thanks for looking that up Gary. I guess they're supposed to be 3/4-ish. Funny, the ones I removed from this 1996 F150 are 1" long, and they looked to be original. I might see if I can get a 3/4" set at the engine shop tomorrow. If not, the 1" ones are going in lol.

Did the flex plate have a bolt ring?
You put the flex plate on the crank then this ring and the bolts, this would pull the threads out a little more.

The only thing I would do is mount it with 1 bolt and then turn the motor over by hand.
I have heard of the bolts being to long and hitting webbing on the block.
By turning by hand if the bolt hit a webbing it would not hurt anything but if by starter it could hurt the threads so it cant be pulled back out or break the block.
Dave ----

Thanks for the reply Dave.

I stopped by the engine shop today and grabbed a pack of 11/16" long (Chevy lol) bolts. Why is it that engine shops are always full of Chevy guys??...lol.

According to the books they had, the bolts were supposed to be 0.6875", or 11/16" long, and they had some. Close enough I guess to the 23/32" Gary noted above. The aftermarket version of 23/32 is likely the more common 11/16, but 3/4" would have been fine also.

I don't remember there being any extra rings on that E4OD flexplate, but I'm guessing it was thicker. It had to have been. Oh well, live and learn. There's always something new to learn about a small block Ford. They keep you guessing, that's for sure. Part of the charm, I guess lol.

Rembrant wrote

Thanks for the reply Dave.

I stopped by the engine shop today and grabbed a pack of 11/16" long (Chevy lol) bolts. Why is it that engine shops are always full of Chevy guys??...lol.

According to the books they had, the bolts were supposed to be 0.6875", or 11/16" long, and they had some. Close enough I guess to the 23/32" Gary noted above. The aftermarket version of 23/32 is likely the more common 11/16, but 3/4" would have been fine also.

I don't remember there being any extra rings on that E4OD flexplate, but I'm guessing it was thicker. It had to have been. Oh well, live and learn. There's always something new to learn about a small block Ford. They keep you guessing, that's for sure. Part of the charm, I guess lol.

Because they are not smart enough to run anything else
You think Ford is hard to find anyone that knows try AMC v8 motors

Fords may not have a ring for the flex plate bolts?
I know some do and why I brought it up just in case it was needed.
I cant remember if Chevy and / or AMC used them as it has been a long time since I played with either (mostly AMC).
Dave ----