351 Cleveland help

[synysterkratos]

Hey guys!
I just purchased a 351C and C6 to replace my 302 and 3 spd manual in my 1971 Bronco. I currently have a 3" suspension lift on it and wanted to know how big of a body lift I might need to get the engine to clear the firewall. From the rough measurements I took with the engine out I will definitely need one. I know I need the adaptor to go to my tcase. I also have block hugger headers on the engine right now but do not know what brand they are. From the reading I have been doing seems like the FC3 headers from Sanderson are the ones to get. Everyone that has swapped please give me some tips and tricks. It would be greatly appreciated.
Thanks!;D;D

 

[Broncobowsher]

351C or a 351M?
The C should fit without any body lift. The M may look like interference with the big block bellhousing.

Now for the C6, is it 2WD or 4WD? If 4WD is it the short extension (~6") or the long extension (~9"). Or at least what it came out of.

 

[synysterkratos]

It is a 351C. The C6 is a 4WD, as far as the extension I have no idea right now. It was built and attached to the engine when I bought it. The guy I bought the setup from had all the work done to the engine and trans.

 

[bax]

The 351C is pretty much a direct bolt up. The motor is wider and the exhaust is very close the the passenger frame. A 1'' body lift will help with the brake booster clearance. the c6 will work but I would find a 205 case and use it instead of the 20. You can use the 20 but some trans pan mods may be in store for you depending on how much spring lift. You said 3'' so you will be very close but should be ok. drive shaft wise the c6 is longer and with a lifted bronco the rear drive angle gets bad quick. I run the c6 but have a Hi9 rear to allow better drive angle.

 

[Broncobowsher]

Do you have any casting numbers? There are a few year to year changes. And I also want to see if it really is a C. Lot of people have an M and think it is a C as they look an awaful lot alike.

 

[Jebus]

In 1970 there were very, very, few 400 m's with a small block bellhousing bolt pattern.
IIRC they were only offered in the station wagons of that year.

All the rest of the 351M and 400M's were big block, (460), belhousing bolt pattern.

Don't know about aftermarket blocks.

On a 351C to the left, from the driver seat, of the distributor, on the block extension, where the flat timing cover bolts to the face of, in front of the left cyl head, the casting is smooth.

On a modified motor, 351/400, that area at the front top of the timing cover protrusion, in front of the left cyl head, there is a cast bar, about 2 to 3 inches long and about an inch wide, that will differentiate the two very easily, along with the bolt pattern of the bell housing...

 

[El Kabong]

None of the 351Cs have that ^ bar (ridge, fin, whatever you want to call the thing at the pointy side of the red arrow), but not all 351Ms/400s have it. So if an engine has the bar, it is a 351M or 400. If there is no bar it could be either a 351C or M. But Ms without are pretty uncommon.

 

[Seventee]

In 1970 there were very, very, few 400 m's with a small block bellhousing bolt pattern.
IIRC they were only offered in the station wagons of that year.

In 1970, there were exactly zero 400's because they hadn't been manufactured yet. In 1973, there was a handful of small-pattern 400s typically with an FMX trans bolted to them.

 

[bax]

Yes 73 only. The block had a dual pattern bell housing cast into it. Everyone that I have seen was drilled in the small bolt bosses only. Also the motor mount bosses on the block were drilled for big block mounts but had the bosses for the small block mounts. All this said we still wonder if the OP has a C or a 400 or a 351M The taller 400 actually fits better into a bronco. The exhaust is higher off the passenger side frame rail.

 

[Jebus]

Ya I knew I wasn't sure of the exact year.

My uncle had a wagon with one in it.

Found out years later how rare the engine was...

I have heard of modifieds without the cast bar by the distributor, but I have never seen one...

Plant build location differences?

 

[bax]

yes but the C never had the raised bar. It's still a good quick reference.