T5 Five speed slant six 74 Dart Sport.

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76Scamp

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Hello! Was not entirely sure where to put this, could've gone either here or under the slant six section, but being primarily related to the trans, this felt appropriate. If not, I apologize. So, I (at least at this moment) have a 1974 Dart Sport as my daily driver. I had built the slant in it, and wanting more performance, an axle that won't break, bigger brakes, and the big bolt pattern, I installed an 8.25 with a 3.55 SureGrip. Fantastic decision. But! Being the car was a three on the tree, highway driving was quite.....bad. To say the least. Being most of my 50 mile commute is done at 60+mph, that had to change. Fuel mileage wasn't horrible, but with the dual Flowmasters, it was not a fun drive. So yes, I know, A833. But I wanted performance and economy, so five gears it was. From a friend, I acquired a rebuilt T5 from an 80s Mustang and the chore began. All part numbers for things I purchased, and even the driveshaft measurement will be included. So if you're an idiot like me that wants a T5 behind the hopped up slant six in their Dart Sport/Duster with an 8.25, you'll kinda know what to do.
The parts list:
Fox body Mustang T5
Resurfaced, stock, 122 tooth flywheel
Gill Welding T5 adapter plate and pilot bearing adapter. Unsure if I could reuse the three speed clutch fork on a four speed bellhousing (can't) I had them drill the plate for the three speed pattern.
10" pressure plate #MU15251. Yes, it's a whole clutch kit, but there was not an easy/cheap way to get just a pressure plate.
McLeod #16061 Throwout bearing for a 440 car
McLeod #8606 Ford pilot bearing
Centerforce 10" clutch disc #280490
Hooker Blackheart transmission crossmember/hoop #BHS578
Silver Sport transmission crossmember #XMM-00400
Ford Maverick transmission mount #2253
Unknown Hurst shifter and T-handle found at a swap meet
Mancini Racing steering column collar for floor shift car (not yet installed)
Driveshaft measured at 52" from the transmission seal to the diff yoke, 51 3/8" from output shaft to yoke. Measurement was taken with the car on the ground and jacked up at the center of the diff. If you do this, measure for your driveshaft just to be 100%.
The Ford to Mopar speedometer cable and transmission tunnel patch are part of a kit from American Powertrain and can be purchased separately if you call in.
I tried to cut as little metal out of the car as possible, but it turned out I had to cut a lot more than expected. The transmission tunnel patch is currently just held down with two self-tapping screws; I don't do metal work or weld. That will be the job of whoever I have replace the floor pans in this car. In the pictures, you will see two different crossmembers. I at first ordered the wrong one and had to overnight the correct one; the zinc plated one is the correct one. It did require some trimming on the end, as did the trans mount, but it bolted together and works; also had to widen the holes a bit for the mount to work. All in, from start to finish (once I had all of the correct parts), this took about a weekend's worth of work and then a couple days waiting on the driveshaft. The Gill Welding adapter is for the overdrive bellhousing, but if you call them, they will drill it for the three speed bellhousing as well for a small additional charge. I did this because, although I have a later overdrive bellhousing, I did not know if I could use my original three speed fork with it. Turns out, I couldn't. The overdrive bellhousing uses a ball stud, where the three speed bellhousing has.... well, I'm not sure how to describe what it is, but it's not a ball stud. I did have to enlarge the opening in the bellhousing to clear the bolts on the transmission input bearing retainer, but otherwise it was a bolt together affair. As you will see, I retained the bench seat that was in the car. If I were to do this again, I would probably try to find a Chevy S10 T5 instead; they have the shifter further forward. The car does drive very well, but I have the seat set back one click from where I would prefer it to be and it is a little uncomfortable. So I will eventually get the seat notched for clearance. Although I did cut a substantial amount of the torsion bar crossmember out, I cut it in a way that the bolt in replacement had to be hammered in, and I then I had welded in place after everything was bolted together. There is a picture of a hole I drilled in the floor; that hole is the rear most portion of the transmission that comes through the floor. If I drive the car nicely, it gets 25mpg. 70mph is now 2000rpm. I have not run the car at the local track yet, so I don't know what it will do given everything else that's been done to the engine.

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THat's some nice work you have goin on! I have all the parts gathered to do the same swap on my slant 6 64 Valiant. I'll be utilizing the original A903 3 speed ballhousing as well as using a Gill Welding adapter. My plan is to start on it as soon as the really cold stuff gets here in Georgia.
 
Thanks for the info, I'm following this one. Like RRR I have the parts for this swap, but so far I haven't decided which vehicle to put it in.
 
Great work! I'm looking forward to hearing what it's like floor-shifting with the bench seat, because I have the same setup in a 65 Valiant and have the 5-speed/rear end work on my 10 year plan. Sure would like to keep that seat....
 
Great work! I'm looking forward to hearing what it's like floor-shifting with the bench seat, because I have the same setup in a 65 Valiant and have the 5-speed/rear end work on my 10 year plan. Sure would like to keep that seat....
That's the easy part. Just get the right shifter handle.
 
Nice job, looking great...

i'm in similar position. really trying not to cut the cross member out, so went with standard bell and clutch, an Aussie ford falcon/ holden 10 inch 10 spline plate, an adapter for bell to trans, Dakota roller spigot bearing. I had my t5 input shaft nose sleeved to .750. think the throw out bearing is dakota or jeep as well, a smidge bigger in the bore and fits well

i took an 80s chevy s10 tail housing with mechanical speedo. machined the scroll at the end of the 5th gear flat like a world class one.
Machined an indent into its circumference for the 5th/reverse brake Tab
Cut 5mm off the end of the 5th shift rail.
And then the NWC s10 housing bolted up no probs and i can shift into reverse.
This rail is longer on T5 transmissions that have a stud in the side of the case towards the rear that isn't the torx or hex head pivot bolt for the reveres finger, and isn't the back up light switch a 3rd THING on that side = long 5th shift rail.

I've a RHD car so the shifter from a camaro that is bent to cover the fact that the camaro has the transmission mounted at a 22* angle works really well for me stick bends to driver

i took the attitude that i'd cut bits off the case and use the truck-centric forward shifter position rather than cut a big chunk out of my floor.... will just have to see

This set up work with a bench seat.

But i aint got it in yet so it all just plans that may not work....

i got the idea for the s10 stuff off thi site from a post here t5 trans swap?
"Cageman" is using a first year s10 , trans mount and hydraulic master 84 or something. check em out on rockauto, all of these parts are different on later s10s take that into account if you follow his plan. the 1st year mount and the 1st year offset clutch master are what he is talking about...hydraulic clutch is just added complexity i'm not bothering


and this is what i did to fit on the s10 tail

Technical - T5 Transmission S10 Tail/extension


i.e you do not have to stick with the annoying ford position that needs to have the cross member hump cut out totally if you move the stick so its not in that position
it also means it would clear a bench seat

however the s10 trans in total would be no good... truck ratio and weaker
its the tail housing you want

for none bench seat people swan neck on the shifter?

Dave
 
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Nice writeup! I think a few people over at .org have done the T5 swap
 
nice work....dumb question, you didn't try find an A833OD first? my slant 6 duster came stock with one, and it is a pretty pleasant drivetrain combo. seems like it would have been a lot less work
 
The 833 overdrive transmission sucks. The gear ratios are spread WAY far apart in first and second. From 2nd to 4th it is a close ratio design. It seems like it was designed for a heavy vehicle making very little power.
 
Hello! Was not entirely sure where to put this, could've gone either here or under the slant six section, but being primarily related to the trans, this felt appropriate. If not, I apologize. So, I (at least at this moment) have a 1974 Dart Sport as my daily driver. I had built the slant in it, and wanting more performance, an axle that won't break, bigger brakes, and the big bolt pattern, I installed an 8.25 with a 3.55 SureGrip. Fantastic decision. But! Being the car was a three on the tree, highway driving was quite.....bad. To say the least. Being most of my 50 mile commute is done at 60+mph, that had to change. Fuel mileage wasn't horrible, but with the dual Flowmasters, it was not a fun drive. So yes, I know, A833. But I wanted performance and economy, so five gears it was. From a friend, I acquired a rebuilt T5 from an 80s Mustang and the chore began. All part numbers for things I purchased, and even the driveshaft measurement will be included. So if you're an idiot like me that wants a T5 behind the hopped up slant six in their Dart Sport/Duster with an 8.25, you'll kinda know what to do.
The parts list:
Fox body Mustang T5
Resurfaced, stock, 122 tooth flywheel
Gill Welding T5 adapter plate and pilot bearing adapter. Unsure if I could reuse the three speed clutch fork on a four speed bellhousing (can't) I had them drill the plate for the three speed pattern.
10" pressure plate #MU15251. Yes, it's a whole clutch kit, but there was not an easy/cheap way to get just a pressure plate.
McLeod #16061 Throwout bearing for a 440 car
McLeod #8606 Ford pilot bearing
Centerforce 10" clutch disc #280490
Hooker Blackheart transmission crossmember/hoop #BHS578
Silver Sport transmission crossmember #XMM-00400
Ford Maverick transmission mount #2253
Unknown Hurst shifter and T-handle found at a swap meet
Mancini Racing steering column collar for floor shift car (not yet installed)
Driveshaft measured at 52" from the transmission seal to the diff yoke, 51 3/8" from output shaft to yoke. Measurement was taken with the car on the ground and jacked up at the center of the diff. If you do this, measure for your driveshaft just to be 100%.
The Ford to Mopar speedometer cable and transmission tunnel patch are part of a kit from American Powertrain and can be purchased separately if you call in.
I tried to cut as little metal out of the car as possible, but it turned out I had to cut a lot more than expected. The transmission tunnel patch is currently just held down with two self-tapping screws; I don't do metal work or weld. That will be the job of whoever I have replace the floor pans in this car. In the pictures, you will see two different crossmembers. I at first ordered the wrong one and had to overnight the correct one; the zinc plated one is the correct one. It did require some trimming on the end, as did the trans mount, but it bolted together and works; also had to widen the holes a bit for the mount to work. All in, from start to finish (once I had all of the correct parts), this took about a weekend's worth of work and then a couple days waiting on the driveshaft. The Gill Welding adapter is for the overdrive bellhousing, but if you call them, they will drill it for the three speed bellhousing as well for a small additional charge. I did this because, although I have a later overdrive bellhousing, I did not know if I could use my original three speed fork with it. Turns out, I couldn't. The overdrive bellhousing uses a ball stud, where the three speed bellhousing has.... well, I'm not sure how to describe what it is, but it's not a ball stud. I did have to enlarge the opening in the bellhousing to clear the bolts on the transmission input bearing retainer, but otherwise it was a bolt together affair. As you will see, I retained the bench seat that was in the car. If I were to do this again, I would probably try to find a Chevy S10 T5 instead; they have the shifter further forward. The car does drive very well, but I have the seat set back one click from where I would prefer it to be and it is a little uncomfortable. So I will eventually get the seat notched for clearance. Although I did cut a substantial amount of the torsion bar crossmember out, I cut it in a way that the bolt in replacement had to be hammered in, and I then I had welded in place after everything was bolted together. There is a picture of a hole I drilled in the floor; that hole is the rear most portion of the transmission that comes through the floor. If I drive the car nicely, it gets 25mpg. 70mph is now 2000rpm. I have not run the car at the local track yet, so I don't know what it will do given everything else that's been done to the engine.

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That's some nice DIY there!

Glad to see you maintained a strong upper transmission crossmember, really essential with a torsion bar car. That crossmember bears all of the suspension loads for the car.

For the shifter, I would think that there are some aftermarket shift boxes that would move the location of the handle some? I see American Powertrain makes one that's really expensive, but I would think there has to be some other options out there...
White Lightning Street Rod Edition Shifter for TREMEC T5

As fas as the tunnel goes, when I ran my 4 speed conversion I did something similar. If you're going to be driving the car for awhile before you have it welded in, I would suggest using a foam tape or similar on the underside of the panel, and running self tapping sheet metal screws every 6-8" or so. Your welder can use those holes for spot welds on the later install after removing the foam tape. In the meantime you'll be a lot happier cutting down on the noise and fumes from the underside of the car.


The 833 overdrive transmission sucks. The gear ratios are spread WAY far apart in first and second. From 2nd to 4th it is a close ratio design. It seems like it was designed for a heavy vehicle making very little power.

It was intended for /6's and light trucks for the most part, so, yeah. Kind of a "band aid" for fuel economy when it went into use.

The 833OD isn't a bad transmission at all, but it's definitely not set up as a performance transmission. I would say that it works well for a driver and it's quite a bit more cost effective than doing a full 5 or 6 speed conversion. But it's kind of a half measure for a more performance based build.
 
Anyone that reads the ratios knows that the 833 OD is not a performance transmission but I had to try one for myself.
My Duster....

Duster 1.JPG

Started off a slant six automatic, I swapped in a rebuilt 360 and 833. Later I wanted to try an overdrive just to see how I'd like it.
It was a poor match for the car.
Sometimes the best impression you'll ever get is the one you felt directly from experience.
I've driven several 83-85 Camaros with the T-5 5 speed. They shifted well and the gear spacing felt great. They can't handle immense amounts of power but a slanty isn't a big block so this ought to work out well.
 
The 833 overdrive transmission sucks. The gear ratios are spread WAY far apart in first and second. From 2nd to 4th it is a close ratio design. It seems like it was designed for a heavy vehicle making very little power.
to each his own....never had an complaints with the ratio spread on mine....granted it's a stock slant 6 in front of it. acceleration is adequate to keep up with modern traffic. the 3.09/1.67/1/.73 ratios are just a touch wider spaced than the 2.74/1.45/1/.69 of a 42RH, granted you don't have the torque multiplication of a torque converter with the A833OD....

depends on how the motor is built. dual plane/longer runners, mildish cam (something in the [email protected]) with a wider lsa and installed advanced (something like a 114* LSA installed on a 106-108* centerline) should make good power down low, and trade off some peak torque for a flatter torque curve that extends higher in the RPM range....
 
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Anyone that reads the ratios knows that the 833 OD is not a performance transmission but I had to try one for myself.
My Duster....

View attachment 1716164561
Started off a slant six automatic, I swapped in a rebuilt 360 and 833. Later I wanted to try an overdrive just to see how I'd like it.
It was a poor match for the car.
Sometimes the best impression you'll ever get is the one you felt directly from experience.
I've driven several 83-85 Camaros with the T-5 5 speed. They shifted well and the gear spacing felt great. They can't handle immense amounts of power but a slanty isn't a big block so this ought to work out well.
I cannot deny that the 833 OD isn't the most optimal regarding the ratios. It's a sad fact. I think Chrysler did the best the could in terms of compromise there. If they had made it a 5 speed instead, it would have been fantastic.
 
to each his own....never had an complaints with the ratio spread on mine....granted it's a stock slant 6 in front of it. acceleration is adequate to keep up with modern traffic. the 3.09/1.67/1/.73 ratios are just a touch wider spaced than the 2.74/1.45/1/.69 of a 42RH, granted you don't have the torque multiplication of a torque converter with the A833OD....

depends on how the motor is built. dual plane/longer runners, mildish cam (something in the [email protected]) with a wider lsa and installed advanced (something like a 114* LSA installed on a 106-108* centerline) should make good power down low, and trade off some peak torque for a flatter torque curve that extends higher in the RPM range....
What engine and rear gear did you run? I agree that a torquey engine with 3.55 and numerically higher gears help tremendously.
 
What engine and rear gear did you run? I agree that a torquey engine with 3.55 and numerically higher gears help tremendously.
my duster is 100% stock, slant 6 1bbl, stock iron case A833OD, 3.23 rear. it's not a speed demon, but it keeps up with traffic better than my daughter's 2014 KL cherokee...if I want speed, I have my late model hemi charger RT....

back in the early 2000's, I built up a 5th avenue with 3.55's, a 42RH with an 1800 RPM lockup converter, and 3.55's. the first engine was a stock bottom end, reringed 360 with headers, and edelbrock air gap, 600 AFB and a comp XE262. replaced that with the original 318 bottom end, lightly ported magnum heads, same intake, carb, headers, but a custom grind on the stock roller cam that was 208/212 @.050, but with more duration @.200 lift than the XE262 and like .050" more total lift on the stock cam's factory 112 LSA, installed at 106. butt dyno, the 318 pulled at least as hard as the 360, but had much better manners, especially off idle, under 2K RPM cruise, and gained like 4 or 5 MPG....
 
my duster is 100% stock, slant 6 1bbl, stock iron case A833OD, 3.23 rear.

back in the early 2000's, I built up a 5th avenue with 3.55's, a 42RH with an 1800 RPM lockup converter, and 3.55's. the first engine was a stock bottom end, reringed 360 with headers, and edelbrock air gap, 600 AFB and a comp XE262. replaced that with the original 318 bottom end, lightly ported magnum heads, same intake, carb, headers, but a custom grind on the stock roller cam that was 208/212 @.050, but with more duration @.200 lift than the XE262 and like .050" more total lift on the stock cam's factory 112 LSA, installed at 106. butt dyno, the 318 pulled at least as hard as the 360, but had much better manners, especially off idle, under 2K RPM cruise, and gained like 4 or 5 MPG....
That's probably pretty snappy right off idle. And that's exactly what the slant 6 in stock form is good at. They came in D500 dump trucks with NP435 transmissions and BIG 2 speed rear axles. Chrysler knew what they were doing.
 
Might be the exact opposite. The 833OD can work well with a lot of low to mid range torque. It's like everything else. If it's built around a certain combination, it can work.
I think you're missing the point.
The deep first gear is followed by a second gear about half the ratio. The rpm drop from 1 to 2 is tremendous. For stock engines with a wide torque curve, this is fine. For an engine with a narrower power band, (Like most 340s or 360s with a long duration cam) the shift to 2nd puts the rpms at the bottom of the torque curve instead of in the middle of it. Close ratio transmissions are ideal for performance engines. The 833 OD is fine from 2nd through 4th/OD if you have some decent axle gearing. The OPs slant six would do fine with a 3.23 or 3.55 gear and this T-5 transmission as well as an 833 OD.
 
nice work....dumb question, you didn't try find an A833OD first? my slant 6 duster came stock with one, and it is a pretty pleasant drivetrain combo. seems like it would have been a lot less work
The main reason is I couldn't find one at a reasonable price, and for what my engine is and how I drive, the gearing in the A833 is subpar at best. The other thing is, with the T5, I have four gears to have fun in vs. only three. And then highway cruising on top of that. I've never dyno'd it, but I would hope I have at least 200hp out of it. Long rod 225, 10.25:1 compression, Clifford cam, header, intake with a Holley 390 double pumper. The head is stock, but I have another that I'm building for it. As it was with the three speed, the car was in the 14s in the 1/4 mile.
For the shifter, I would think that there are some aftermarket shift boxes that would move the location of the handle some? I see American Powertrain makes one that's really expensive, but I would think there has to be some other options out there...
White Lightning Street Rod Edition Shifter for TREMEC T5
That looks like a very nice piece. But I don't think my wallet thinks the same way. I drive this car every day; it is my only vehicle and sees up to 100 miles per day on average. I've gotten adjusted to how it is, but I would like to get the seat notched around the shifter. Seat needs some new springs anyway, might as well have that done while it's at the shop. Only problem being I need another car first.
 
I think you're missing the point.
The deep first gear is followed by a second gear about half the ratio. The rpm drop from 1 to 2 is tremendous. For stock engines with a wide torque curve, this is fine. For an engine with a narrower power band, (Like most 340s or 360s with a long duration cam) the shift to 2nd puts the rpms at the bottom of the torque curve instead of in the middle of it. Close ratio transmissions are ideal for performance engines. The 833 OD is fine from 2nd through 4th/OD if you have some decent axle gearing. The OPs slant six would do fine with a 3.23 or 3.55 gear and this T-5 transmission as well as an 833 OD.
No I get it and I agree to a certain point. The trick is to not puss out on the gear, like Chrysler did. They used the 3.23 and the 3.55, both of which are sorry gears for an OD transmission. More like 3.91 or 4.10.
 
The 833 overdrive transmission sucks. The gear ratios are spread WAY far apart in first and second. From 2nd to 4th it is a close ratio design. It seems like it was designed for a heavy vehicle making very little power.
What you say is true,
but the fix for a streeter, as I found out, is to put Second gear where you need it, and let the rest fall where they may, then put a hi-torque 360 in front of it.
A good Second gear on the street with a 360 is not more than ~6.80.
The 833od has ratios of 3.09-1.67-1.00-.73od. To get 6.80 Second you need 6.8/1.67=4.07 rear gears, rounds to 4.10s Thus the Road Gears become
12.67-6.84-4.10-2.99, and 65=2400rpm, about perfect for a hi-torque cam.
While the 12.67 is pretty low, it is however a perfect parade gear, as 4mph=630 rpm ,
and the hi-torque 360 will pull that 6.84 Second gear from 2000 to 6000 all day long which is ~26 mph to 80 mph; and street tires are gonna be boiling most of the way.
I mean I really liked it, especially when I installed 4.30s, (but that novelty was short-lived) except I kept forgetting it was a 3+1, and so the od gears had a habit of shattering...................................... lol
But what you say is absolutely true. Every word.
 
No I get it and I agree to a certain point. The trick is to not puss out on the gear, like Chrysler did. They used the 3.23 and the 3.55, both of which are sorry gears for an OD transmission. More like 3.91 or 4.10.
A 3.91 or 4.10 would be good and still deliver decent highway rpm with the A833. With a 27" tall tire and a 3.91 gear, you would be almost 2600rpm at 75mph; about 2700 with a 4.10 with the A833 overdrive. With my slightly smaller tire (26.85") and the slightly better .68 overdrive, I turn almost 2300rpm to do 75mph; engine sounds very happy there. It used to turn about 3300 for 75mph before. I drove it two hours to the Don Garlits Mopar show last weekend and got 30mpg holding 75mph the whole way. I am unaware of what the other gears in this transmission are, besides 4th of course. Just did some math to figure out what OD was and haven't gone any further. This transmission was in a 65 Mustang that kicked the driveshaft out at 150mph, but only cracked the output housing. Guy decided to upgrade to a TKX instead of fix the T5. He said the T5 had an upgraded gearset, was rated for 400hp, and cost him $3500 at the time he bought it.
 
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