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I upgraded my 72 Mach 1 with an AOD from a C6. I preferred to go with a 4 speed toploader not only because it is a virtually indestructible but a stickshift is a built-in anti-theft device and most of all......a hot rod should have a stick! I costed all the parts and compared them with a simple auto to auto changeout and of course the AOD was definite cost savings. I really wanted a stick but economics ruled it as it was 3K more than the AOD. Also, had I known that the TV cable system is such a pain to deal with, I would have gone with a stick. Anyway, the pricing seems fair to me since I had priced all the materials two years ago. The one thing I question is the use of a clutch cable. When I was researching all the parts i needed for the changeout, I downloaded an exploded parts list for the OEM clutch system. There is a series of springs, levers and other gizmos that will give you a solid yet easy way to push the clutch pedal without fatiguing your left leg in traffic. The question is how will the simple clutch cable method translate to force needed to push the clutch pedal down. You might research the use of cable vs the use of a hydraulic clutch system. A hydraulic clutch is more to buy and install but the results may be worth the expense especially if you want to make your Stang a daily driver..
As a feedback, with my cable system with MD it takes some strength to do. Obviously, this is very subjective. It is fine around town and most of the 98% driving I do. When in heavy traffic it can be tiring after a while (HRPT traffic). I have never tested a linkage system to compare. Just comparing to my previous two 4Runners, it id heavier. However, if I compared to my 1978 Land Cruiser it would have been on par or lighter.
I think a hydraulic clutch system would be nice but I was already stretching my budget back then.
 
My experience is different than Tony's ^^.

I suspect Tony has a higher performance pressure plate which requires more effort given his higher performance 408 stroker motor. Am I right Tony?

I have two other Mustangs ('69 & '70) with factory Z bar clutch actuators.

The cable clutch I installed in the '73 requires significantly less effort than either of those cars. So much so that when I first did my conversion I was worried that something was wrong and I wasn't engaging the clutch.

If I was stuck in stop and go traffic I'd much rather be in the '73 with the cable clutch. YRMV.
 
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$4,382.77. Add in all the labor. Not considering the decrease in wear on the engine with the O/D, I wonder how many miles you'd have to put on the car for the gas savings to pay for the build?
As a DIYer, I have to factor in the enjoyment of retrofitting the 5-speed into my car, the satisfaction of the completed job, and the pleasure of driving a manually shifted classic Mustang. It adds up to very worthwhile! Fuel efficiency doesn't factor in for me since I'm currently running a 3.89 gear and AOD.

Also, as a DIYer, I enjoy tracking down good used parts I can rebuild or restore and use in projects like this. In my case I'll be using a WC T5, factory shifter and bellhousing I've had in my shop for a while. I'll source whatever parts I need from MDL and others, as needed to complete the project.
 
My experience is different than Tony's ^^.

I suspect Tony has a higher performance pressure plate which requires more effort given his higher performance 408 stroker motor. Am I right Tony?

I have two other Mustangs ('69 & '70) with factory Z bar clutch actuators.

The cable clutch I installed in the '73 requires significantly less effort than either of those cars. So much so that when I first did my conversion I was worried that something was wrong and I wasn't engaging the clutch.

If I was stuck in stop and go traffic I'd much rather be in the '73 with the cable clutch. YRMV.
I guess it boils down to the spring strength of your chosen pressure plate as to which clutch system you would want to use.
 
I've done two toploader 4 spd to T5z conversions and I've loved both! I used the factory flywheels, bell housings, and transmission cross members, but used the adapters between the transmissions and the bell housings. The factory shifter arms even bolted up directly to the T5 shifters. I changed the slip yokes but didn't have to modify the driveshafts. Both cars had 351Cs putting out around 350HP, and I beat the hell out of both of them. The T5z's never failed, even through dumping the clutch at 2000 rpm and power shifting throughout. I can't say the same about a regular T5 though. I tore two of them up. As for clutches, I agree with 351c1971. The Centerforce clutch 11" clutch kit with the stock linkage is the way to go. Like he said, the pedal is very light and feels like it has a hydraulic assist. All in all, that is the "best bang for your buck" IMHO. It is so much easier if you already have a standard setup though. I've seen kits to easily add the clutch pedal to an existing automatic pedal support. Then all you need is the clutch rod and the Z bar setup. Here are the cars I converted.



1973mustangmach2015.jpgIMG-7611.JPG
 
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My experience is different than Tony's ^^.

I suspect Tony has a higher performance pressure plate which requires more effort given his higher performance 408 stroker motor. Am I right Tony?

I have two other Mustangs ('69 & '70) with factory Z bar clutch actuators.

The cable clutch I installed in the '73 requires significantly less effort than either of those cars. So much so that when I first did my conversion I was worried that something was wrong and I wasn't engaging the clutch.

If I was stuck in stop and go traffic I'd much rather be in the '73 with the cable clutch. YRMV.
Correct. My clutch is rated up to 600hp and it is from MD. I dont have data related to the pressure plate.

Edit: Modern Driveline MD-KS7-1016, 10.4" kevlar/organic w/steel back facing
 
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With all this going on about manual transmissions and such, I have a question. Way back when I owned my 78 Mustang II, I changed the clutch disc and pressure plate several times. The original reason was the disc was worn out and I did a full change out…..disc pressure plate and throw out bearing. All was well for the first few weeks then it felt as though the clutch was slipping. Lots of vibration when transitioning from a dead stop onward in first gear. Shifting the other gears had no issues. What caused the vibration? When I bought the car, it had only 18K miles on it and shifting was a breeze. I got fed up and changed out the pressure plate again and had the same results. A guy at work has a 78 corvette and he has the same problem. Any ideas??
 
Possibly an issue with the flywheel. Was it resurfaced?
No. The flywheel looked to be in good shape with no grooves or pits. My Mustang II had only 35K miles on it. I thought maybe it was a bad pressure plate. When I changed it out the second time, the disc was still near perfect and so was the flywheel. I did the same thing with my 75 Granada with a 3 speed stick. The flywheel was chewed up and I did get that one resurfaced....luckily there was one parts house in the area that could do it. Also with a new pressure plate and throw out bearing. That job went well with no issues and it drove well when I sold it. My thoughts were that the pressure plates were shoddy rebuilds since I bought the replacements at Hi-Lo.
 
My mechanic put in 2 aftermarket stock clutch kits from different brands in my 2001 GT. Both pressure plates failed in less than 200 miles. I finally gave him a CenterForce, made in the USA, dual friction clutch kit to install. That fixed the problem. BTW the dual Friction kit does have a VERY positive engagement which plays well with my Prothane motor mounts.

There seems to be quality issues with many replacement aftermarket clutch kits, even in the professional channel. I had 140,000 mi on the OEM clutch before replacement, so it was definitely not a driver issue.
 
Did you check to make sure the bellhousing is aligned when installed on the back of the block? If the bellhousing is off center of not square with the block then the transmission input shaft may be under stress, either off center or not perpindicular to the flywheel. Either of these could cause uneven clutch engagement.

 
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Did you check to make sure the bellhousing is aligned when installed on the back of the block? If the bellhousing is off center of not square with the block then the transmission input shaft may be under stress, either off center or not perpindicular to the flywheel. Either of these could cause uneven clutch engagement.
This is a very important point often ignored. Thank you for bringing this up. I spent a lot of time aligning my bellhousing to the block per Tremec TKO requirements. I had to install some very thin shims to align. I forgot the thickness of these shims but they were very thin and there were a chore to keep them in place when installing the bellhousing. As a reference, Tremec instructs to keep the run-out to within 0.005" fo the TKO.
I am attaching a document with instructions and Tremec's instructions.
 

Attachments

  • GM Dial Indicating - RobbMC instructions Revised 6-15-09A.pdf
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  • TKO Installation Tips 02052018.pdf
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My experience with installing the TKX has taught me to check and correct the engine block/flywheel parallelism to the bellhousing first.
After reading and recording the out of center runout, it was reduced into the acceptable range by installing (very thin) shims between the separator plate and bellhousing.
In my case they were installed at the 12 o clock position.
Boilermaster
 
The bellhousing is located with 2 large dowel pins. I assume that if the block, bellhousing and transmission are OEM and the components that the car was born with, there should be no alignment issues. Does this make sense, or am I missing something?
 
351c1971,
Not true,
The toploader 3 and 4 speeds use a straight roller bearing input shaft bearing, whereas the newer Tremecs (T's too,I think) use a tapered roller bearing, very different tolerance.
IMHO all of the straight roller bearing transmissions will also run smoother and last longer with the bellhousing (dialed in)
think of this as blueprinting for your transmission.
Boilermaster
 
The bellhousing is located with 2 large dowel pins. I assume that if the block, bellhousing and transmission are OEM and the components that the car was born with, there should be no alignment issues. Does this make sense, or am I missing something?
Think of it like when you blueprint engine components. In theory all should align perfect but in practice there always is tolerance stacking or aging that makes things deviate. Thinking about it, I used 0.0015" and 0.005" shims to align my bellhousing to meet the 0.005" spec. This is a very small amount and it probably would have worked okay without going through the trouble but life expectancy and shifting smoothness would have suffered. The smoothness of TKO's are known to be very sensitive to this spec along the lines of what @boilermaster alluded above.
 
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