Vintage Mustang Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
172 Posts
Discussion Starter #1
I have a 64 1/2 coupe that I am going to sell unless I can put an overdrive transmission in it. I have been told that because it is a 64 1/2 the bolt pattern will prohibit me from using an AOD. I was also told that the only option was to use an early 4 spd bellhousing with a T-5 behind it. If anyone could explain the situation I would appreciate it. Thank you.
 
G

·
Guest
Joined
·
0 Posts
The T-5 bellhousing cannot be used. You should be able to use one of the adaptor plates available to use your original bellhousing and the T-5 together. In addition, you will need a new crossmember, yoke, and maybe drive shaft shortned, as you would with any conversion. Check with NPD. they have all the necessary items needed.
 

·
Registered
Joined
·
21,263 Posts
The problem is that early 3 & 4 speed transmissions have a "narrow" bolt pattern, such as the early 5 bolt bellhousing. IIRC, in 66, the bolt pattern for manual transmissions was changed to a wider bolt pattern. The transmissions from then on were drilled for both patterns, making it easy to install a late trans into an early car, but not the opposite.

I don't know if there are any wide bolt pattern, 5 bolt bellhousins. I don't know if the 5 bolter has the meat on it to be redrilled. Since I haven't done a T5 swap, I don't know if the adapter could be modified.

Seems a shame to get rid of a 64.5 car because you can't put OD in it.
 

·
Premium Member
Joined
·
3,428 Posts
Bob, I like the looks of that. Any experience with them? Might be good for phase 2 or 3 of the coupe project.
 

·
Registered
Joined
·
10,587 Posts
Not impossible, just in need of a little creativity....*G*

Years ago, I designed adapters for PowerGlides to run behind SBF's and 385 series Fords...it's not rocket science...

If I had a AOD bellhousing and early 5-bolt C4 bellhousing and a little piece of 3/8" or 1/2" aluminum plate, it would be relatively simple, as the two bellhousings using the same datum locator dowels IIRC, and likely share much of the same bolt pattern. Then, it would be a simple matter to make some converter spacers for the pads (the central register should be deep enough to still register correctly on the crank). IIRC, from my friends C4/AOD swaps, the converter fits fine, BC-wise. Lastly, a correct rear trans mount would be required to allow for the longer unit length. In most cases, the driveshaft should be OK but should be checked...

Just wanted you to know it's not impossible, and is something I'd consider for my D-coder if I drove it alot on the freeway...

Find a good local machinist who understands what you want and I'll bet the solution will be pretty affordable; likely, including rebuilt AOD and converter, half what a GV over/under costs...

Good luck!
 

·
Registered
Joined
·
172 Posts
Discussion Starter #8
Thank you for the advice, however given my lack of transmission knowledge could you suggest a technical manual or drawing that would allow me to envision what the adapter plate would look like in order to convey the message to a machinist. Also would you be interested in making a technical drawing and selling it to me perhaps? Certainly paying for your know how will be a lot cheaper than the Gear Vendors solution ($$ is a concern as I am still in school). Thank you again for your time.
 

·
Registered
Joined
·
10,587 Posts
Just imagine superimposing a 6 bolt block plate over your 5 bolt one, noting what bolt holes line up and what ones don't (most should)....the plate will simply bolt to the block (with flat head allen bolts where the holes don't line up) and the bellhousing will bolt to the plate (some bolts will go all the way through and others may be short, terminating in the plate)

To account for the 1/2" or so further back the transmission will be, appropriate spacers can be made to space the converter back a like amount (in racing apps, we use bolts which thread into the converter, simplifying this step)

Lastly, the holes in the trans crossmember are slotted or an adapter is made, allowing the rear trans mount to correctly mount 1/2" or so further back. The driveline is then checked for correct clearance and shortened if necessary.

Since the flexplate still mounts to the crankshaft as per stock, starter mounting and operation are unchanged. I belive a similar flexplate is used with the AOD (ring gear-wise) as with the C4. I don't know if there are differences in BC, but these can be easily remedied through correct crossing of part numbers or through machine work.

As I don't have the requisite block plates (especially the 5 bolt one) readily at hand, it would be time prohibitive for me to attempt to do an accurate blueprint of such an adapter. I do have core 6 bolt C4's so that part of the equation isn't a problem. I'd have to take the D-coder apart to get the 5 bolt dimensions and my getting that kind of greasy isn't something you could likely afford *G*

If you took a 5 bolt block plate and a 6 bolt AOD (which is the same bolt pattern as the later C4 IIRC) to a machinist and told him you want that bellhousing to fit the block plate bolt pattern with an adapter plate, he'd know what to do.....it might be possible to do the modification without a plate, but I'd have to have the requisite parts in front of me to advise on that possibility.

Hope that helps!
 

·
Registered
Joined
·
254 Posts
I think you have the right approach but I don't think it is that hard. I took my 6 bolt block to get dipped at the machine shop, and as it turns out, it was a 5 bolt block that they welded on a 6th hole and tapped it out at the factory. I wonder if you could just put a 6 bolt bell housing on with 5 bolts?
 

·
Registered
Joined
·
10,587 Posts
As the thrust of my development was to adapt a GM transmission to a Ford engine, I have little knowledge of the actual bolt patterns and register similarities and differences between the 5 and 6 bolt Fords. Until I bought the D-coder in '93, I had never even seen one, having built and raced later engines during my career.

I would tend, instinctively, to agree with you...but wanted to discuss a worse case scenario, much as the ones I faced with the Powerglides, where no bolts nor registers lined up..

I prefer smiling when the job turns out easier than I expected rather the frowning from the reverse, if you know what I mean..*G*
 
1 - 12 of 12 Posts
Top