by Keith Bettencourt
Have you ever wished for one more gear in your Tiger? After you have pulled out onto the freeway, accelerated up to cruising speed, do you have to turn the radio up because you can’t hear over the exhaust? Do you come home from trips tired and with your ears ringing? Would you like to cruise the freeways at 2000 RPM instead of 3200 RPM? Does a 20% increase in highway fuel economy interest you? Would you like to cut a second (or more) off your 0 to 60 times? If you answered yes to any of the foregoing, then you may be a candidate for a Mustang 5 speed transplant. The Mustang 5 speed, and its heavy-duty cousin, the Ford Motorsport 5 speed are both adaptable to your Tiger. I’ve go one in mine and I have met two other guys (at SUNI) who had done it also. The difference between their transplants and mine is that they grafted in late model 6 bolt 302’s with the Mustang 5 speed bellhousing, and I used an early model 5 bolt 289 (same bolt pattern as the Tiger 260) with a custom made bellhousing to transmission adapter.
If this idea appeals to you, here are the basics:
- You will have to CUT your car at the body brace that is directly under the ashtray. There is no way around this. The 5 speed shifter is integral with the transmission, and it comes through the center of the floor 4?1/4″ further back than the stock hole. There is not enough room to move the engine forward or backward to avoid the “C” word. The cut is approximately 4″ wide and 8″ long and will weaken the body somewhat, but I have ridden in a Tiger with a 5 speed and a 450 HP, nitrous fed 302 that runs high 12’s in the quarter, and it does not flex any more than any other Tiger I have ridden in.
- A new transmission mount cross member will be required. The 5 speed transmission mount is 1?3/4″ further forward and lower than stock so that no matter what you do to the stock mount, it just will not fit.
- A transmission mount “wedge” will have to be fabricated because the 5 speed mount is angled about 5 degrees from horizontal when the transmission is aligned on the bellhousing. You can’t tip the transmission to compensate because there is not enough room (see #9 below).
- Use the stock Tiger rubber transmission mount but rotate it 180 degrees and file one of the mounting holes a bit.
- A short straight custom shifter is required because the Mustang unit is too tall, leans the wrong way and (even if reversed) ends up in the wrong place at the wrong time.
- A new speedometer “driven” gear will be required. It will clip right onto your existing speedometer cable. Choose one that matches your choice of rear end gears and tires.
- The driveshaft needs no modification. Slip it in and bolt it on.
- The clutch needs no modification, the 5 speed input shaft is the same size and spline count as the Tiger unit.
- The engine will have to be removed to perform this transplant. You need a lot of “wiggling room” to slide everything into place. The 5 speed is wider toward the rear of the transmission and that is exactly where it fits into the tunnel that is at the center of the frame X-member. I slid mine in from the bottom (with the radiator and front end removed) and that worked fine. I do not know how easy it would be to try this from the top, but my guess is the angles may make it difficult to impossible.
- You will have to fabricate a new sheet metal tunnel cover for that 4″X 8″ hole in the floor.
- A custom carpet piece will have to be made since your old 3″ circular hole is now exposed, plus you now have a new floor contour around the shifter.
- Kiss your console good-bye. You can use part of it if you remove the ashtray and cut about 4″ off the back. It really is not too tough, but if you are new to mechanics, better get some help.
As you can see, the Motorsport 5 speed has ratios that are very similar to the Tiger II transmission plus the addition of that lovely cruising gear! With a stock 2.88 rear end and either transmission you will get better dig out of the hole, eliminating the dreaded “Tiger Bog”, plus you get the cruising gear. Even if you go all the way to a 4.56 rear end, your effective final ratio will only be 2.87. The Motorsport 5 speed is a good choice if you have a high horsepower engine or “big” gears. The Mustang 5 speed has the “lowest” first gear, so it’s a good choice if you want to run the stock rear end or a radical cam because it gives better torque multiplication. You can also pick them up at a bone yard for about half the price of a new Motorsport unit. Such a deal!! I really cannot think of a single performance drawback with this swap, but you will have to decide if you want to cut your Tiger to have the benefits.
Editors note: This description gives a good overview of installing a stock Mustang T-5 in a 260 Tiger. There are now many other installations on the road using 302 Mustang engines, 302 Motorsport crate motors and even 345 stroker motors. Some T-5 transmissions are modified and rotated so that the shift lever comes out near the original position and cutting of the body is not required. Some use a very rare AMC tailshaft, some use a Chevy S-10 Pick-up shift tower and there are modifications of all the above. I’m sure at any TE/AE event, the owners of these cars will give you a complete verbal description of their installation.
The use of the 302 Mustang T-5 transmission with its clutch, flywheel and 6 bolt flywheel housing simplifies the installation but requires cutting the center crossmember and shortening the center console by 2 1/2 inches.
It is recommended that if the center crossmember is cut, that a box section be blended into it directly behind the cut section to maintain the strength of the body.
The complete powertrain without the water pump is easily installed from the top.