I keep hearing large vs small discussion on tranny humps in the cab.

Is this soley determined by which transmission cover is installed? Or is the tranny tunnel larger on one vs another rig?

What is mine?

1974 ext cab f250 2wd factory 390 and C6.

Reason I ask is my mazda gearbox m5od-r2 is really tight in the tranny tunnel. Will make clutch changes quite difficult.

My tranny cover had manual hole covered with a plate screwed shut.

I moved the access hole about 3 inches aft. And I shortened the mazda gear lever 3.5 inches to accomodate the tranny apparantly sitting higher in cab then earlier manual transmissions.

Thanks for any help offered.
Brigart

 

If i'm remembering correctly all 4X4 have the pan that bolts to the floor. All 4 speed trucks have a pan bolted to the floor. If you look at your floor in the middle you will see an out line of where it gets cut out and the other bolts down. You will have to drill the holes for bolting it down. The hole is aprox 12'' wide, maybe 18-24'' long. Makes it about 2'' higher with the pan.

 

So my 79F100 has a 302, three on the tree. If I go with a big block and c6, I will have to acquire this cover and cut out the recessed area on the hump?
I haven't made up my mind on what engine & tranny yet. I plan on leaving the bench seat in it, so I'm assuming most standard trannys that are performance oriented might not be a good option. I would think the shifter would be too low and hard to reach

 

It's easy to tell which you have.
The basic floor pan is the same. Look under the carpet/mat. If you have a removable transmission tunnel cover, then you have the high hump version. If the floor pan is one piece with no removable cover then you have the low version.
I don't think you will need to do any floor mods for a C6. There doesn't seem to be any one answer on how Ford decided which floor pan to use. My '73 F100, 2WD, 360/C6 had the high version with a removable cover. My '75 F100 2WD, 360/C6 had the low hump version.

 

^ What he said about checking to see if it's removable or not. Every time someone comes out with a "rule" about if the truck should have a high tunnel or not, other people will chime in to voice their "exceptions". Ford really seemed to lack a method to the madness with that one.

 

Brigart I have to ask how did you get a small block ford trans to bolt up to a round bell FE. Is there an adaptor that I am not aware of?

 

The C6 came in a variety of bell housing patterns. I assume he used the one that is compatible with the FE engines rather than adapting the SBF version.

Edit: According to his signature, he also swapped to a 300 I6 (though he didn't mention it in the post).

 

Sorry I did not do a google search first before asking. Found it. Thanks. This opens up a lot of options now

 

I pretty certain that you will not need the removable pan for the C6.. if you do, its nothing to trim that section out and put a removable cover in it.. The divot that the outter diameter of the pan sits in is stamped into your floor already.

 

Here's a picture of an automatic floor pan.. Do you see the indent in the center hump? You can mark 1" all the way around the INSIDE of that line and cut it out then bolt a standard plate to it.. I did it on my 66/78 conversion..

Instead of drilling the holes and using bolts and clips I used heavy duty self tapping screws to fasten it to the floor..

 

This is my transmission tunnel. It is from a 4x2 manual. Started out as a 3 spd on the tree then a 4 speed T18. Now it is a 5 speed.