Gen 3 Subframe Write-Up?

[1995mtxsho]

Has anyone attempted to write down all that is involved in the conversion?
I would like for those that have tackled it to post up! List materials, parts needed, specs, tips, etc...

Thanks.

 

[Phoenix]

Talk to Marcel , he got it done.

 

[93rev2sev]

I beleive the only thing that you need to fabricate is motor mounts. I hope someone chimes in...It's definately on my list of mods.

 

[St Louis SHO]

Do a search, and all shall be revealed. Thats how I found out....

 

[K-Dawg]

There's lots of different ways to go about it, depending on what you want to do.

 

[St Louis SHO]

There's a few guys out there that will build you one too. Try NESHO. He did it first, and has built many.

 

[JEM]

Has anyone attempted to write down all that is involved in the conversion?
I would like for those that have tackled it to post up! List materials, parts needed, specs, tips, etc...

No, I haven't written mine up, but there's lots of info out there in a scattering of posts.

My take:

a) A post 5/98 SLO subframe is the way to start, the rear mount tower can be used mostly as-is. Considerable surgery is required on the subframe to make the MTX V6 powertrain fit - I think I've posted pix of my mods. I've got my car together with reinforced SHO engine mounts, though I'm now contemplating a set of Volvo S80 hydraulic mounts if I can figure out how to add a torque-control dogbone up top...

b) The Gen 3 SHO steering rack is a ZF Servotronic item, infinitely higher-grade item than those on other SHOs or Tauruses though its ratio is a bit slower than the Gen 1 rack. I'm the only one thus far who's bothered to wire up the Servotronic variable-assist, though at the moment I've got it unplugged. If you buy a used rack you will probably want new inner and outer tie-rod ends. Make sure to get the rack heatshield/pressure line support.

c) Power steering plumbing requires some work, you will need to adapt the Gen 1/2 pump hard-line end to the Gen 3 rack (you'll find other posts on this) and you will need to reshape the Gen 3 return line and adjust its routing to the cooler along the inside of the left subframe rail.

d) I think I'm also the only one who's used the Gen 3 steering intermediate shaft and the Gen 3 upper and lower rack-to-firewall boots. If you search my posts you'll find the pics of this arrangement; the Gen 3 shaft 'phases' better. This requires some trimming to the firewall, which I think is needed anyway.

e) The front crossmember of the Gen 3 subframe is shaped and located differently than the earlier subframe; things that bolt to the crossmember like the cruise-control servo and the power steering cooler will have to be adapted. Personally, I think the PS cooler belongs up in front of the car. I used the cooler set I'd had in my black car, since I've also got a trans cooler and pump in the car, though I'd made a nice little prototype bracket for relocating the stock PS cooler to the front of the car (another option in MTX cars is to use a Gen 2 ATX trans cooler for the power steering.) I haven't yet reinstalled the cruise control servo (I use cruise control about twice a year anyway.)

 

[Mr Anonymous]

d) I think I'm also the only one who's used the Gen 3 steering intermediate shaft and the Gen 3 upper and lower rack-to-firewall boots.

Negatory.

 

[zak]

As I am painting my Gen III subframe conversion this weekend, I can tell you I researched it pretty thoroughly, including NESHO's and JEM's approaches. Either approach requires a jig to be made to locate the trans mount and front mount, rear mount in some cases. It takes ~ 6 to 10 hours of fab time plus materials just to make the jig up properly, and NESHO's is the nicest one I've seen (locates in complete 3D, better accuracy). As my local speed fab place wanted $60 hr (x 10 = $600) just to make the jig up I ended up very happy that I went to NESHO to get the conversion done. Mine is a unique amalgam of Kirk's and JEM's approaches using a low mileage '99 SLO wagon subframe as a starting point (I supplied the latter to NESHO).

Powder coating of subframes is a whole 'nother subject . . . if I lived in Michagin I would have went black cathodic oxide epoxy electrocoat (e-coat).

 

[K-Dawg]

d) I think I'm also the only one who's used the Gen 3 steering intermediate shaft and the Gen 3 upper and lower rack-to-firewall boots. If you search my posts you'll find the pics of this arrangement; the Gen 3 shaft 'phases' better. This requires some trimming to the firewall, which I think is needed anyway.

I have a new Gen 3 intermediate shaft. I noticed that the two ends are rotated a couple degrees in relation to each other (instead of being 0, 90, or 180 degrees off). I thought that was odd.

 

[JEM]

I have a new Gen 3 intermediate shaft. I noticed that the two ends are rotated a couple degrees in relation to each other (instead of being 0, 90, or 180 degrees off). I thought that was odd.

The Gen 3 shaft is nearly phased correctly (not quite, but close.) The Gen 1 shaft is way off.

http://ww2.borgeson.com/DESIGN/STEERING DESIGN7.html

The only thing I can conclude is that Ford intentionally 'unphased' the earlier shafts to make the nylon-lined telescoping section move up and down during use, so that it didn't wear in one spot over time.

 

[JEM]

As I am painting my Gen III subframe conversion this weekend, I can tell you I researched it pretty thoroughly, including NESHO's and JEM's approaches. Either approach requires a jig to be made to locate the trans mount and front mount, rear mount in some cases. It takes ~ 6 to 10 hours of fab time plus materials just to make the jig up properly, and NESHO's is the nicest one I've seen (locates in complete 3D, better accuracy).

Fabricating the jig isn't that big a deal, but you need a Gen 1/2 subframe to build it on. I'd say six hours is an outside number as long as you've got sufficient steel scraps around to play with.

You also need a Gen 1/2 subframe to cut up in order to get the transmission mount bracket. I actually ended up putting the bracket on the Gen 3 subframe twice - tacked-on once to trial-fit the transmission and determine how big a notch was needed, then the bracket was removed to notch the rail, then the bracket was put back on permanently. The bracket hangs over the left side of the rail and needs a support fabricated to hold the rear end.

I've seen conversions that left a big hole in the subframe rail for transmission clearance, I personally do not find this approach acceptable as it removes too much metal from the rail right in the area where the rail is already holed for the control arm to pass through. I spent the time to box in the hole with sections from a piece of 3x5x.125 rectangular steel tubing:

Before: http://www.milleredp.com/gallery/v/jem/motion/SHO/subframe/DSCN0599.JPG.html
After: http://www.milleredp.com/gallery/v/jem/motion/SHO/subframe/DSCN0601.JPG.html

If I were doing this again I think I'd invest in having the subframe blasted to clean it off before doing the work.

 

[SuperHO]

So who wants to convert my 95 MTX for me??