On Wednesday, I introduced you to my Mustang II and described some of its unique features. Today, I’m going to show some of the work it took just to upgrade the driveline. This story may not be for everyone, but it represents eight months of my life, and after such a commitment, I felt the need to share. Mustang Soul Survivor
I would also like to take this opportunity to shout out to my buddy Paul Regner. All the work on this project was done at his house, and without his help it would not have happened. Adding to the challenge, we did all the work with the car in his driveway on ramps and a pair of jack stands. Not too shabby for a pair of fifty-somethings!
As you may recall, I replaced the carbureted 2.8 L V-6 and Borg Warner four speed (the SR-4) with a fuel injected 2.9 liter V-6 and Borg Warner five speed manual transmission (the T-5). The 2.9 shares the same block with the 2.8, so the engine swap was literally bolt in. Other than hanging a wire harness to run the fuel injection system, the engine swap posed no real challenges. In contrast, the transmission work forced me to assemble a new unit using major parts out of three different car lines, and required me to invent my own transmission spacer.
On paper, the work looks pretty simple. Both transmission cases include a Ford part number, they share similar dimensions, and both use a top-loader main case with a single internal selector rod. Even better, both transmissions used a common bolt pattern on the front of the case, which led me to think I could bolt the T-5 up to the existing bell housing.
Based on that information, it looked like a weekend project. However, as I gathered the pieces to complete the project, I discovered there are a lot a factors involved, and there was no off-the-shelf solution.
Before beginning this project, I had a number of outcomes in mind:
1) With the seat adjusted for my height, the factory shifter location was a little too far forward, so I wanted to maintain the existing location. Ideally, I would have liked to move the shift lever further rearward, but that did not happen.
2) I wanted to maintain the existing clutch linkage (if possible), in order to maintain factory operation and reliability.
3) I liked the existing gear ratios, so I wanted to maintain the factory ratios in the new transmission.
4) I wanted to maintain or improve my existing shift quality. The engine bay isn’t packing huge torque, so upgrading to one of the high torque aftermarket manual transmissions wasn’t necessary.
5) I wanted to do this all on the cheap. While I’m willing to pay for quality, the list price of some aftermarket transmissions exceed the book value of the car. It’s hard to justify spending $5,000 on a $2,500 car.
Typical Ranger Bell Housing with Hydraulic Release Assembly
Ford bolted three different five-speed transmissions to the 2.9 (or 4.0) liter Cologne V-6: the Borg-Warner T-5; the Mazda M5OD; and the Mitsubishi FM-132. Regrettably, all three transmissions used a hydraulic mechanism to release the throw-out bearing, rather than the cable system used in my Mustang. I could adapt the T-5 to my bell housing, but the Japanese cases both used unique bell housings which would not accept the Mustang II’s clutch linkage. In the end, the T-5 offered improved shifting over the older four speed unit, could use the existing clutch linkage and was available in the junkyards with multiple gear ratio options. Based on all those factors, the T-5 appeared to be my best option.
This is actually a Fox Body T-5 on a Mustang II bell housing, but you get the idea.
With that decision made, I looked into the best option in terms of gear ratios and case dimensions. Based on shifter placement and gear ratios, the T-5 used in early 80’s F-Bodies with the (GM) 2.8 V-6 looked good. The gear ratios for first through fourth matched my current transmission perfectly, and the shifter mounted at the very back of the tail shaft, for the best shifter placement. Looking around the local junkyards, I found one in a Firebird priced at $155 and after spending a couple of greasy hours at the yard, I thought I had come home with right the transmission.
These are both T-5 transmissions, and the internals swap.
But you can see that the bolt patterns are very different.
Another fun fact- In order to match up the F-body transmission to a Ford bell housing, I needed to swap out the Chevy main case to change the bolt pattern. Jeep and Ford main cases both bolted up to the Ford bell housing, so I found a Jeep case on E-Bay to solve that minor set back.
Based on the tape measure, there were several critical dimensional differences between the original transmission and this T-5. First, the T-5 was about an inch shorter in overall length. Second, the shifter placement moved forward two and a half inches as compared to the original transmission. Lastly, the input shaft on the T-5 was about 1″ shorter than on the original transmission. While the differences were all relatively small, it meant my T-5 wouldn’t properly mate to the clutch and flywheel, would place the shifter too far forward, and would require a longer driveshaft. So much for a simple project!
This picture from the net shows what can happen if you don’t watch your lengths. As you can see, the shifter on this II is VERY close to the radio. In addition to the interference issues, this shifter requires monkey arms to reach fifth gear. After researching other Mustang II T-5 swaps on the internet, I determined my bell housing was the primary issue. It was much deeper than the bell housings on newer cars, and no American T-5 came with an input shaft deep enough to mate to it.
I found several articles about Mustang II T-5s on the internet, but the solutions I found often involved compromises I didn’t care to make. In some cases, the input shaft did not fully engage the clutch plate, and in every case, the shift handle moved forward on the transmission tunnel. In fact, several people built custom shaft levers, just to clear the radio faceplate! I needed a different solution, and thanks to the internet, I found one.
During my research on the T-5, I found a chart listing the various input shaft lengths. As you can see, almost every car uses a unique input shaft. I was looking for shaft at least 9 -1/4′ long, and nothing here in the US matched up. However, the Holden Commodore built in Australia exceeded my needs by a comfortable margin. After making a few phone calls, I found a Transmission shop in New South Wales that sold me a used shaft for $75, with shipping costs that barely made me scream.
Here’s a picture of some T-5 input shafts. Starting from the left, we have a 280Z T-5 part, a shaft out of a Fox Body Mustang T-5, the original shaft from the Mustang II four speed, and the Commodore solution. Clearly, the Commodore shaft includes enough length to fit the Mustang II’s bell housing. Unfortunately, the gear tooth count on this shaft did not match up to the gear set in the Camaro transmission. Because of that, I ended up getting a second T-5 out of a Fox body Mustang. The gear set differed slightly from my old transmission, but allowed the use of the Commodore input shaft. Once it arrived, I installed it in the new T-5 and mated things up.
As this picture shows, the shaft extended well past the face of the bell housing. Clearly, I could now mate the transmission up to the clutch plate. However, I now needed to space the transmission back from the bell housing. On the upside, the new shaft would place the shifter in the correct location on the transmission tunnel.
This photo shows better shows the new challenge. To accept the Commodore input shaft, I needed to move the transmission back about 2 1/2″.
To make this happen, I cut 2-1/2″ off the front of the old four speed transmission.
By placing this spacer between the bell housing and transmission, I maintained the factory throw-out bearing and clutch linkage, and the case bearing provided a perfect centering guide for the bearing retainer on the T-5. I didn’t even have to cut down the Fox body bearing retainer–it was the perfect length to mate with the spacer!
The parts mated up. There’s a cover for the top of the spacer, but I left it off so you could see how the transmission bearing retainer mates to spacer
Here’s an image of the bell housing, spacer and T-5 transmission on the bench . As you can see, the parts look like they belong together, and line up perfectly.
Finally, here’s the base of the shifter handle in the tunnel opening. As you can see, it also matches perfectly. It took a ton of research and effort, but I did not have to compromise on shifter placement, which I consider a major victory!
From here, the project was very simple. I had a shop shorten the existing driveshaft 1″ (my new input shaft and spacer turned my too short driveshaft into a too long shaft), and my buddy Paul welded up a very lovely transmission mount to mate the T-5 to the existing hard points in the body.
That’s the story of the transmission in a nutshell. There were a few more twists and turns I chose to leave out, including a false start with a 280Z input shaft and a pile of leftover parts. But they didn’t apply to the final result, so I skipped over them.
So you may ask, was the effort worth it? As measured in the real word, probably not. The work is buried under the car, and leaves the exterior looking perfectly stock, so most people have no idea how much work this project took. In addition, I’ve invested a ton on time and money into a car that will never increase much in value, so from a dollar and cents standpoint, the project is also hard to justify. But having said all that, I’ve derived huge satisfaction from this job. Having a fifth gear makes the car five times more pleasant on the highway, and I bought the car to drive.
Would I do it again? Only after I build a shop with a lift and purchase a full set of fabrication tools!
A closing note: On Wednesday night, the Soul Survivor and I successfully arrived in Las Vegas for the Mustang’s fiftieth anniversary. While I’ll check into your comments when I can, the lures of Sin City will undoubtedly keep me away from the computer for most of Friday. For those of you with questions, the answers will come in the fullness of time.
Great job and story! The real satisfaction comes from knowing you achieved your goals through research and application of thinking skills. You also did it in a low tech environment.
Ouch. As something of a Cologne V6 fan, I thought the only thing needed to fit a T-5 to a v6 was the Mustang II 4 speed-v6 bellhousing. You should have just gone with the European T-9, or Mt75 out of a Sierra/Scorpio instead. I prefer the T9 (and I have two v6 transmissions at home, although one is the weaker 2.3 v6 version), but the Mt75 handles the v6 power a lot better. I am currently (well, after 7 years, I won’t finish it I guess) building a tuned up 2.8 carb’d v6 with a Cosworth 2.9 crank, so I have been looking into the T-5 conversion, but now I will rather get an uprated t9 when the original box blows up…(and it probably will, they are known for blowing up on weaker engines too)
PS, I also think the shifter comes to far bac in some cars with the T9, which in your case would possibly be a bonus.
Here in the US, there are very few T-9s in the junkyards. Almost all US Scorpios were automatics, and the XR4Ti’s (Sierra) T-9 uses a four cylinder bell housing.
Nothing in the US market used an MT-75, so we have zero knowledge of that transmission.
Yes, offcourse, but finding one on ebay and having it shipped from Europe probably could have been easier (maybe not cheaper though, good v6-transmissions are getting rare) than finding parts from Austraulia 😉
I think 4 cylinder version would work with a different bellhousing, but still need a new input shaft to not lose it’s splines
Still a great story, and very interesting for those who want a T-5 for their V6.
Nice work!!!!!!! How about a CC on the rig with locking hubs in the background??
Great job! You really did your homework on this. I love how you fabricated your own spacer by cutting down another transmission case.
I like doing these kind of re-engineering exercises too. I looked into adapting an A518 4-speed auto in place of my A727, but the tail shaft is so much larger that there wouldn’t have been room for my console shift linkage. I wound up adding a Gear Vendors OD.
*VERY* nice article ! .
Thanx for the details , your tranny spacer solution is simple and effective , the very basis of true Hot Rodding .
-Nate
I was going to say the same thing — nIce job DS. Look forward to hearing how the car did on the trip.
I’m very impressed. It’s such a complete write up, it really doesn’t allow for any questions. I really can’t imagine doing all this work on a driveway using only jack stands, out in the desert heat, but that of course, just adds to the accomplishment. Very cool.
I admire your energy and enthusiasm and determination, not to mention calling Australia!, but it’s too much work for me now. I could (and did) do something like that decades ago, but I wouldn’t even think of starting something like this now…*sigh* getting old sux.
I am reminded of a phrase that was attributed to a Mercedes Benz engineer, but that’s probably apocryphal…”Why do it the easy way when it’s just as easy to do it the hard way”
I commend you for doing all of that with primitive working conditions…anything is possible, given enough resources, but your ingenuity and ability to get this done without spending a fortune is impressive.
What an awesome project! The motor installation looks stock and not kudged at all! I’m glad that you made it work for your Mustang, ’cause that year is my favorite one of the II generation. I do wonder why you didn’t swap in a AOD automatic from a ’79 Ford? It might have been simpler.
Here’s the gear ratios.
First: 2.400:1
Second: 1.467:1
Third: 1.00:1
Overdrive: 0.667:1
Reverse: 2.00:1
Presumably he wanted to continue to row his own gears. In that car, I would too.
I’m not sure the AOD ever bolted up to the Cologne V-6. The Scorpio came with an A4LD, which has a so-so reliability reputation. However, the Scorpio and Ranger PCMs would run the torque converter lock up solenoid, so it would be the obvious choice for an overdrive automatic.
Above and beyond my preference for row your own, I also had no idea how well an automatic would fit in the tunnel. D/S
Great writeup; thanks!
Kudos Dave! That is TRUE hot rodding…and re-engineering! My hat’s off to ya…
“So you may ask, was the effort worth it?”
These kind of conversions never make economic sense. They are done to make the vehicle what you want it to be, and easier to live with. You have achieved that goal admirably.
I have a friend who, years ago, did a 5-speed conversion on a Jaguar XJ-S. You may as well have backed the Brinks truck up to his house, plus he took a bath on it when he finally sold it. But, it’s what he wanted.
I remember reading about the debate over whether to fit a 5 speed to one of the European Fords, economically it didnt make sense because people would only use the fifth gear x% of the time (not very much) and it would therefore only save a small amount of fuel. It would of course make the car more pleasant to drive and much more saleable instead of having it struck from consideration lists with only a four speed. I suspect not much has changed!
Nice write up and very nicely done job! I’m glad you didnt need to find the top Group A Commodore input shaft, you would have been chasing one of less than 2000 cars built!
What rpm did you end up with? I’m guessing around 25-2700 rpm for 75 mph which would work well.
FWIW I’ve just done a 500-ish mile trip to Bathurst in a Hillman Imp, using about 4000-4500 rpm cruising speed (no tacho in the car). Also no easy 5 speed option but at nearly 40 mpg all it would achieve would be a change in engine notre pitch and the need to change down more often for hills!
I am deeply impressed. Me? I’m still congratulating myself on changing a Cortina head gasket in a supermarket car park 30 years ago!
MK3 Zephyr gearbox in a drain roadside was a lovely job we had the parts in the car it let go on the way home from the junkyard too many engine mods and the cases warp.
Quite a mission fitting that well done I love backyard bogan engineering but you need a good shop. I noticed the group A on your list yeah as John said quite a rare car to source parts from A neighbour of mine had a T5 equipped 253 VH Commodore with strut brace and race suspension and the moment the relaxed the rules around that race class out came the T5 and in went a Toyota Supra box apparently stronger he said.
Dave, great perseverance seeing this project through. Somewhere out there, your research and hard work will be of great benefit to someone who one day will think “I wonder how my Mustang II would run with a 5 speed in her?”
Job well done! American Backyard Engineering at it’s finest!
Dave how about a video of the engine running and maybe a quick walk around of the car?
How did you make such a nice, clean cut in the old transmission (to create your spacer)?
Good question-
I handed it to a guy at the machine shop, and then handed him $125. Probably overkill, but there’s no telling how true the faces need to be for this application. Because of this, I paid for the cleanest cut possible. The machine shop option was still cheaper than having an adapter built to specs.
According to the machine shop guy, he used a deep throat band saw for the initial cut, and then milled the face flat.
You are one smart guy. Nice job. On behalf of all of us late 50 old farts, I say, what do you think about that, junior?
Your project got me curious about Mustang IIs so I did a little research. Sounds like a set of “subframe connectors” from a kit or custom made will really transform your car.
What a fantastic tech article. I thought of buying a V6 Pinto and then swapping in a rwd Ranger 2.9L V6 and attached five speed. The ratios probably wouldn’t have ideal. Would have perhaps meant a conversion to hydraulic and perhaps the shifter wouldn’t have come out in the right place. Yours is done right but lots of research and work. Nicely done.
Well done. You sweated the details and got a superb result. I guess you will write about the engine swap.
This project reminds me what I had to do to revive my Isuzu Impulse back in ’05. Isuzu never officially sold cars in Venezuela.
When I bought the car, the transaxle was in pieces sitting in the boot. I had one of the mechanics from the shop check the whole mess and after spreading the bits on the footpath he declared “it’s doable”. However, the output shaft had some teeth with “dents”. I pointed to that and said “that will get replaced” to which my friend said “no worries”.
We were scratching our heads on how to source the remaining parts, mostly hardware, when the 2 magical letters showed themselves in the diff carrier: “GM”. One car sold by GM should have something we could use… if we were lucky.
After some investigation… the car appeared. The 2.2lt Cavalier did have the “same” tranny. The inconvenience was that the FDR was 3.57 instead of the original 4.117. So off to source one…
When I finally found it, we started the repair process. My friend reassembled the gearbox (he was very talented at that and as machinist) and we fitted it to the car. Which lasted a couple of minutes because a bolt was loose and chewed the 5th gear :(. No worries, we pull the Cavalier 5th gear and… the bloody thing didn’t bolt right up, he had to make a spacer to fit. And then, done.
I don’t know how much acceleration was killed with the mod (it could still smoke the tyres), but the little thing could go easily at 80MPH at 3K RPM. Perfect for what would become my daily commute some months later.
I hope that you’ll have a lot of enjoyable miles from your one-of-a-kind five-speed Mustang II. I’ve done a couple of mods longer ago than I really care to think about, but they were mere kludges compared to your work on this project. Congratulations!
You have my lifelong admiration for the quality of your driveway engineering. Maybe you are the guy to supervise a conversion of the son’s Grand Marquis to a 5 speed. Or better yet, a 3 on the tree with an OD unit. Kidding.
It sounds like a ton of work, but you came through it all with exactly what you wanted. Very, very nice.
Good job but it looked to be quite a hellacious project. I still have dreams of replacing the 3-speed column shift on my ’65 Belvedere slant 6 with a T-5 but I’m not sure if it will be more of a nightmare than anything.
Now ya need to put a 427 in front of that 5-speed. 🙂
Been there, done that- Jack Roush built a 460 powered Mustang II back in the seventies.
Link:
http://www.hotrod.com/featuredvehicles/hrdp_1009_hot_rods_past_feature_cover_cars/
Excellent work and write up Dave. You have a lot of intestinal fortitude to complete a daunting project like that. I was going to convert a 2003 Subie Outback from auto to 5 speed (which will bolt in as long as you have the manual driveshaft) but the electronics/wiring were the ‘no way’ moment. The ECU, wiring, cam sprockets, etc. were different and I could find no examples of anyone doing it without having engine light issues. Since we have emissions testing here in CT, I finally said uncle.
I’m not sure if your Outback ever came with a 5-speed manual, but if the manufacturer built the car with your desired driveline, and you have a different driveline, the best option is to trade in your car, and find one with the driveline you prefer.
You’ll lose money on the transaction, but I’m sure it’s cheaper than doing the job yourself.
I’ve been thinking for fun that I would put a late (67 Ford) Borg-Warner T86 with overdrive into my 71 Maverick with the mighty 170. My project is much easier though, as the transmission case is six bolt, as is the pattern on the back of the 170 bellhousing, and the input shaft length and spline count matches the three-speed in there now. Even the front bearing retainer is a match to the hole in the bellhousing. Basically a bolt in. Being a truck driver, the non-sync first gear is no problem! I’ll let you’all know.
That’s essentially what I did with my ’66 F-100, with the 240 six. And since the OD in mine is manually engaged, I can use it on all three gears. Plus, the free-wheeling makes shifting into first a bit easier than when OD is not engaged.
I did have to shorten the drive shaft. I suspect you will too.
Nice job! I put a T5 and a 2.6 in my 71 carpi this year and I agree, lots of time invested on the internet researching. I went the same route as you minus the spacer. How did you get the starter work with out being engaged all the time?
thanks again for the article
robbyj
Robby J-
I just noticed your post, so sorry for the lengthy wait to reply. The spacer goes between the the transmission and bell housing, so it does not affect the starter to bell housing depth.
I did recently discover that the starter for the 1990 – 96 Ranger 4.0 V-6 (Automatic only) bolts up to the 2.9. This starter provides greater torque and better starting.
The manual transmission starter physically matches the bell housing, but the bendix drive does not extend out far enough to mate with the flywheel.
Thanks for the reply Dave and the info for the ranger automatic starter. For my setup I used 4.0 manual transmission starter and a 1/2″ starter shim for a ford V8. Does your 2.9 have a spacer between the flywheel and crankshaft? I believe the 2.8 Mustang II had a spacer. I bolted the 4.0 flywheel directly to the crankshaft. This might be why I had an always engaged problem.
thanks
robbyj