A833-to-727 Conversion

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340-4spd

340-4spd

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So I picked up a SB 727 for the Duster. Guy I got it from said it came out of a truck. So anyways, since the 4sp is on it's last legs now want to try that for awhile, see how it does, just for something different. Looks to be in good shape, so I'm thinking I'll get a flexplate and torque converter for it, pull the pan, inspect, replace some seals, throw it in, fill it up and see what happens. If it does OK maybe I'll install a shift kit.

Couple things I'm wondering about at this time:

1) Torque converter suggestions?

2) Flexplate/flywheel issues? Do I need to replace the flywheel with a flexplate that has a ring gear for the starter?

Thanks, guys.
 
340-4spd said:
So I picked up a SB 727 for the Duster. Guy I got it from said it came out of a truck. So anyways, since the 4sp is on it's last legs now want to try that for awhile, see how it does, just for something different. Looks to be in good shape, so I'm thinking I'll get a flexplate and torque converter for it, pull the pan, inspect, replace some seals, throw it in, fill it up and see what happens. If it does OK maybe I'll install a shift kit.

Couple things I'm wondering about at this time:

1) Torque converter suggestions?

2) Flexplate/flywheel issues? Do I need to replace the flywheel with a flexplate that has a ring gear for the starter?

Thanks, guys.
Click to expand...

1) I don't clame to know that much about ATs, but your torque converter will depend on what gear and tire height you plan to run with it so that you will know the RPM range that it will usually be at on the highway. I was always told that your cruise RPM range needs to be higher than the converters stall range is.

2) The ring gear is attached to the converter as one unit.
 
I recommend the B&M Flexplates, they're nice and beefy pieces.

Aside from that, you're gonna want the Neutral Safety Wiring Harness and you'll have to modify the wiring a little bit if your car is a factory 4-Speed. I did on my '74 anyway. I was running a '72 340 4-Speed Interior Harness (with 3-Speed Wipers, A/C, Rear Defrost, Map Light, ect) with a '74 318-A/C Engine Harness. Had to change some stuff at the bulkhead for the Neutral Safety to work/connect.

Also, hang on to your 4-Speed Pedals.

When i converted my '74 Duster to a 727 i traded my 4-Speed Pedal setup for an A-Body Center Console that needed restored. Figuring the 4-Speed Pedals weren't worth crap/dime a dozen pieces, when i later found out they were highly sought after ](*,)

It's ok though, i later bought a car ('72 340 4-Speed Demon) from the guy, and my pedals were laying in the trunk when i picked the car up :toothy7: He forgot to remove them from the trunk when he was cleaning the parts out of the car. I built 2 sets of 4-Speed Pedals based/designed off those ones :toothy7:
 
74Dusted said:
Also, hang on to your 4-Speed Pedals.
Click to expand...
The first response to this post was somebody offering to buy the 4-speed stuff. Go figure.

But anyway, this car was originally a 318 column-shift automatic. I installed a manual column and scrapped the auto column, so that's the only real stumbling block I see right now. I suppose there must be any number of aftermarket floor shifters available I could make work with a little persuasion. I am also considering what to do about the kickdown. Should be straightforward, assuming I can obtain a few bits and bobs of that linkage somewhere. I recall seeing something about lokar kits, etc. Any recommendations on the kickdown? I like reusing cheap, stock scrapyard parts, but if anybody has any experience comparing the two, I'm open to suggestions.

Not too worried about the the wiring, although I noticed the harness/wires is still on the trans, so I will have to hook that up to at least get the backup lights working. But thanks for the heads up, anyway. :yawinkle:
 
You don't have to much on the wiring. The neutral safety switch comes right up the back of the engine, and regardless of the original harness, there will either be a connector from the center of the NSS that will fit right onto the starter relay, or you may have to extend the harness and add a spade push-on connector for it.

If your starter relay only has one "push on" connector, it's the older type for stick shift with no clutch safety, you'll have to buy a starter relay for an auto

If this TF is a 2wd trans, it should be the same length as your 4 speed, and your driveshaft should fit. Be sure to yank the speedo gear out of your 4 speed if it was correct.

Most guys on here seem to like the Lokar aftermarket kickdown, something I'm gonna have to deal with, or install a man. valve body I have.
 
OK, I'll continue to cheap out on this project, since the Duster is basically just my beater toy anyway. Gears are optional, I have three sets I can use: 3.23, 3.73 (currently installed) and a set of 3.91s waiting to build whenever I get around to it. Rear tires are 27" tall. What's anybody think of this converter?

http://cgi.ebay.com/ebaymotors/ws/e...515822&ssPageName=STRK:MEWAX:IT#ht_852wt_1165

Will it do the job? Worth the money?

Wish I knew more about the autos...
 
So I got the converter for $65, and picked up some ARP flexplate bolts and a pair of low-profile 16" wide plate coolers I'll run in tandem mounted down in front of the radiator near the top of the bumper somwhere.

Looks like all's that's left for parts collecting for this project is a shifter, flexplate, and some kickdown linkage. I like the looks of the Lokar stuff and will probably go with that for the shifter and kickdown. Odd, the trans itself ends up being one of the lower cost parts. :-s
 
Looks like this project is just about in the bag. Parts breakdown:

Trans $75
Converter $65
Bolts $9
Cooler(s) $26

Still to buy:

Yoke $70 (est.)
Flexplate $30
Shifter $200 (est.)
Kickdown $90 (est.)
New DS Work/Parts $150 (est.)
Various Materials $100 (est.)

It ends going over $800 for this little job. :rolleyes:
 
340-4spd said:
So I picked up a SB 727 for the Duster. Guy I got it from said it came out of a truck. So anyways, since the 4sp is on it's last legs now want to try that for awhile, see how it does, just for something different. Looks to be in good shape, so I'm thinking I'll get a flexplate and torque converter for it, pull the pan, inspect, replace some seals, throw it in, fill it up and see what happens. If it does OK maybe I'll install a shift kit.

Couple things I'm wondering about at this time:

1) Torque converter suggestions?

2) Flexplate/flywheel issues? Do I need to replace the flywheel with a flexplate that has a ring gear for the starter?

Thanks, guys.
Click to expand...

I'd adjust the bands, raise the pressure, and change the filter while the trans is out and pan is off. If you have a standard "A" body 4 speed you will have to shorten the driveshaft.
 
I have the complete setup you need in my 69 dart. good console and shifter.727 with 2500 stall .driveshaft.Im wanting to go 4 speed. if we could do some tradeing let me know
 
The trans will get a band adjustment, filter, rear, shift and dipstick seals. Not sure about the front pump seal. I'll leave that alone if it looks clean when I pull the old converter off. It will also be getting a whole new drive shaft built.

Sorry Don, but I'm keeping all the 4-speed stuff so it can can go back to being a 4spd after I rebuild that trans in case I ever decide to do that.
 
Looks like I'm approaching the point where I'll be ready to actually install the transmission. Completed mock-up of the coolers/remote reservoir, and relocated the battery to the trunk to make room for a good place to install an external filter.

Should be about another day's work getting the cooler mounts fabbed up fitted and bolted in. Depending on when and how much time I get to work on it, a launch date for the 727 of sometime in the first half of SEP seems reasonable. One thing I'm still not too sure about is the trans mount. It's a long tail-shaft, so there's going to be something unusual required there...
 
The supporting mods I decided to do for the auto are pretty much finished:

http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_57.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_58.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_59.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_60.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_61.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_62.jpg

I'm trying to improve on the stock cooler without using it at all to keep the heat sources from the engine and trans separated. I think the coolers are power steering units from a Nissan truck. The coolers and remote reservoir (aluminum tube, which also acts as a heat sink) will be daisy chained back through the filter sitting where the battery used to be. I used #2 welding cable to connect the battery from it's new location above the rear axle back to a bus block with a jumper lug just below the starter relay on the inner fender.

I plan on capping the reservoir tonight, pressure test it, get the correct hose barbs installed at various points and put the bumper back on. Things still to purchase are tubing, clamps, temp gauge, driveshaft, shifter, kickdown linkage and a transmission jack. I'm pretty sure the total price tag for this swap will exceed $1k after I go back and tally it all up.
 
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_64.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_65.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_66.jpg

Some things I wanted to do with this setup were improve on the stock cooler, while keeping cost down. Using the low profile plate coolers mounted down low blocks very little of the main radiator airflow, so cooling should remain good or better than stock all around. I think I have maybe a total of $50 in parts including fittings and clamps. The coolers came from eBay for $10@.
 
So the 4sp and all associated hardware is out as of yesterday. The 727 is ready to go in, probably starting on Monday. I noticed the overall length of the unit from the block mounting face to the tailshaft seal is only maybe a couple inches longer than the A833/bellhousing unit. Should be an easy fit.

In the process of removing the clutch and pressure plate I spied an un-used 3-pin plug on the wiring harness up along the top of the firewall that I suspect is for the transmission electrics - neutral/safety and backup lights. Anybody have a clue as to the wiring color/stripes for this thing? I'm hoping l can rig it up to plug into the trans I have, because the neutral/safety switch has a 3-pin socket.

This car was originally a column-shift 318 automatic - soon to be a floor shift 340 automatic.
 
I am running the Lokar kickdown in my car and I love it. I had a hell of a time trying to get the right mechanical linkage to work with the four barrel. I also went with the Lokar accelerator cable and it looks very nice.
 
Yes, I am going with the Lokar kickdown and shifter - looks like nice upgrades to the stock parts. Just not sure about which shifter, trans mount or floor mount. I'm leaning towards the floor mount since it would seem to offer the most mounting flexibility.
 
So the trans is in. Plumbing, shifter & kickdown and driveshaft is all that's left. This turned out to be a huge job including "un-flipping" the spring hangars to get rear end back up where it's supposed to be. You need one of these, or something like this to put a long tailshaft tranny in an a-body:

http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_67.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_68.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_69.jpg
http://stuff.is-a-geek.net/PhotoAlbum/Cars/Pics/duster_70.jpg

There were a few reasons I decided to go with the long tailshaft. There's millions of them around, with used ones going pretty cheap. The short tail transmissions tend be somewhat rarer, in my experience. Plus the long ones are available from trucks with the stouter 4-pinion planetary. You also end up with a few inches shorter driveshaft. Paired up with the 8.75 in my duster, the driveshaft measures only 46" joint center to center.

Ordered that today, should have the car back on the road next week. :cheers:
 
Aiight, the results are in, to mixed reviews. Got everything back together and went for a few test drives yesterday. Trans is good, shifts as expected, loved the Lokar stuff. Now for the bad: Looks like I got boned on the eBay torque converter. Car exhibits a bad pulsating vibration in all gears at anything near or better than 2k rpm. When will I learn to stop buying stuff off eBay? :banghead:

So looks like it's coming apart again sometime in the near future. How about some torque converter recommendations? Engine appears to be a stockish forged crank 340 with 3.73 gears and 27" tall tires.
 
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