Engine and Trans Swap Questions

James · Post by **James** » January 21, 2008, 4:07 am

Still trying to decide what to do with my stock drivetrain, it is tired and in need of TLC. Have a '66 F100 with a 352 automatic.

I have an opportunity to purchase C6 rebuilt by Ford of Canada, is there any way to mate this square top bellhousing to my 352 or a 390?

What is involved in swapping my 352 for a 400? I have an a line on a decent 400 that will mate up to the C6.

Am I better off rebuilding the C4 and my motor or rebuilding the C4 and installing a 390?

I realize that I am all over the map, just want to make the best choice and get on with it! Keeping in mind that money is a factor.

Thanks
James

banjopicker66 · Post by **banjopicker66** » January 21, 2008, 11:03 am

James, I did a 352/three speed to 352/C-6, then swapped it all out for a 460/C-6.

One thing you must realize is that the C-6 bell housing is part of the overall casting. You have to get a C-6 that mates to the engine you are installing it on, or get an adapter - an expensive alternative, in my book, not worth the money to me.

Your C-4 in there now has a removable casting for the bell housing, but the C-6 does not. (You can swap the innards from C-6 to C-6, but I do not know the exact interchangeability.) You cannot put a 400 C-6 on anything but a 351M, 400, 429 or 460. A 351W or 302 C-6 will only fit those 2 (I think), and the FE C-6 will only fit the FE family of engines.

If you change the engine, you will face the following issues:
Engine mounts and perches (need to be from a 400 equipped truck - a complete parts truck is the best way to go on this)
Radiator hose locations
Carb linkage
Exhaust routing

If you change the transmission, you face the following:
Shift linkage (completely different parts from C-4 to C-6)
Tailshaft length and type whether slip joint or fixed
Driveshaft length and type, whether in-line slip joint or single piece
Rear transmission mount

There are probably more, but these come readily to mind.

If I had to do it all over again, I would not have changed the engine family. I love the 460 power, and get decent mileage, but until I start using it like a towing truck, it is way more than I need, and was more than I intended to do.

Instead, I would have replaced the 352 with a built 390, which would have simplified many small details as well have reduced the time and frustration in doing the swap. I think your idea of rebuilding the C-4, and dropping in a 390 would be the best way to go, for simplicity, time, frustration levels and cost.

Good luck however you decide to go!

Johnny Canuck · Post by **Johnny Canuck** » January 21, 2008, 11:15 am

I agree with john da Picker. You can built a C4 up to be just as tough as a C6. EZ way to go IMO.
a 400 would be a step in the wrong direction, given the chices you have given us.

Hawkrod · Post by **Hawkrod** » January 21, 2008, 11:54 am

Just a quick point, he does not have a C4 in his truck. Ford never installed a C4 behind an FE. He has a Cruisomatic. You can buy a custom bellhousing to install a C4 behind an FE but they are pretty expensive (about $450 for most brands). Hawkrod

dotcentral · Post by **dotcentral** » January 21, 2008, 12:35 pm

Hawkrod wrote:Just a quick point, he does not have a C4 in his truck. Ford never installed a C4 behind an FE. Hawkrod

Yes, either you got a C6 behind that 352 or you really have a 351 with a C6, FMX, or C4 transmission

banjopicker66 · Post by **banjopicker66** » January 21, 2008, 1:56 pm

Hawkrod is right, it is a COM - you can tell by the green dot on the shift indicator.
My books distinguish between a COM for light cars, and an HD COM for heavy duty in the larger cars (like station wagons) and pickups.

Jarrod · Post by **Jarrod** » January 21, 2008, 2:50 pm

As far as I know, a FMX is not a Cruise-O Matic. If I were in your spot, I would nix the 400 and go straight to the 460. Same bolt pattern and cheaper to rebuild and you will get way better reliability and power out of it. If you must have the 400, Hot Rod Mag did a 400 build that made great power, but it used Mopar 360 rods on a custom crank with some different pistons. It was a bastard engine but it ran well. 460's are easy to get and cheap to build.

oldtrucks · Post by **oldtrucks** » January 21, 2008, 3:10 pm

James

IMHO I would have the trans you have rebuilt and build your 352 up the same way you might do a 390. You will be very suprised at how powerfull a well built 352 is and it won't break the bank and you will avoid all the swap issues changing to a different engine family. Different mounts, cross member problems, drive shaft issues. The list goes on and on.

I like the FE engine family as you can tell. I've got a middle 70's 390 C6 combo just sitting here. Both need rebuilt. $500.00 for the pair if interested. I am going to list it in the parts for sale just haven't done it yet.

Have fun what ever you decide to do.

James · Post by **James** » January 22, 2008, 3:06 am

Thanks for all the help. I have the green dot on the shift indicator so I will assume at this point that I do in fact have the cruise-O-matic. What are the thoughts on rebuilding a COM?