I am looking into getting a new steering box for my 66 mustang. At some point I would also like to install a new tilt steering column in the car. How do I know if I need the short shaft or the long shaft?

 

All 66's came with the long shaft. (goes from the box to the wheel) A short shaft has a coupler about 1ft from the box.

 

Your 1966 came with a long shaft. 1965 through 1967(?) had long steel shafts from the gearbox to the steering wheels. To remove the gearbox would take some work for those years. Ford changed the Mustang steering box from a long shaft to short shaft for two reasons: the short shaft box was needed for cars with tilt-wheel options and for the coming introduction of the collapsable steering column. A collapsable steering column can be used to upgrade a 1966, but you will need to gather other parts (gearbox, shaft, pitman arm); I'm not sure what other pieces are needed.

Try this website and look towards the bottom of the page:

http://www.stangerssite.com/steeringboxtagdecoder.html

I hope this helps.

 

So with that said if I switch to an aftermarket tilt steering column, do I want to do the short shaft since that is what was used with tilt columns in later years?

 

To go with an aftermarket column, one way or another the long shaft has to go.

I suppose it may be possible to cut the shaft and have it splined or something, but once you do this you are probably better off changing the box, they are not that much. IDK if you can bolt in a later short shaft box or if it is more complicated... someone here knows though...

We used a rack and pinion setup including a new column, if you have the means I highly recommend this swap, it is most righteous, makes the car drive a lot better.

 

typical order for installing an aftermarket column would be:

remove current column
rough cut off long shaft with sawzall
disconnect and remove steering box from car
exact cut length of shortened shaft and drill hole to attach U-joint
reinstall box and new column

 

JMD, curious what rack and pinion you are using? I've considered it strongly to get a rack and pinion but I have heard many mixed reviews about them. Loss of turning radius and hard fit, and especially for me since I have a 6 cylinder. I understand they will not fit the same in the v8 as the 6. Just figured it would be easier to replace the steering box and system, which also ended up being cheaper. I do have a rare p/s 66, and want to keep power also.

 

We used a Flaming River manual rack. This was a six cylinder car, and we used the rack some while it was still a six, but we did change the spindles to 8 cyl at the same time. I am not sure if the rack would work with the six cyl spindles or not.... If the tie rod ends are the same size on both 6s and 8s it should be no problem.

In any case we are really happy with this rack, but as I said it is manual, I have heard some folks say that the power racks are prone to leaking, but IMO these are OEM style racks (Mustang II or Pinto) that are used in the kits and I would think that they should be reasonably reliable.

The car turns easy and short, handles much better than stock and there is no "bump steer".

 

That makes sense.

I did not know for sure that the bearing and seal in the top of the steering box are suitable for the added load that a shortened shaft might incur, and if they are suitable for the additional environmental exposure that would be present when the column external tube is removed... So I left that answer for someone who knows...

I think if it was my car I would want the shaft either splined or machined/cut/ground to properly fit a Double D. A hole and pin would worry/bother me too much...

 

That's interesting about your flaming river rack and pinion. Most people have said to stay away from them because of bumpsteer and clearance issues. I've seen where they advertise a power rack just for the 6 cylinder. So you don't notice a difference in your turning radius? Was there any difficulties in installing it? I'm still undecided about whether to do a brand new steering box from flaming river and refresh the p/s system or the rack and pinion... Like I said I heard many bad reviews and I don't want to spend $2K for a product I won't like.