4spd swap checklist for a 68 Dart GT 318/904

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there was a 8 and 3/4 sure grip center recently listed here for I believe $900.00. It was a good gear 391 if I remember right. 355 is my favorite but depending on what your looking for maybe it would work for you. I did the Coronet R'T in 1982. but I had a complete donor car and we made the 440 body into an R/T. I sold it years later after doing an old school lacquer mopar "electric blue" paint job with white vinyl top. Dude did some tach wiring to it and it burnt to the ground along with his garage and it caved in on top of the car. I should have never sold it to him.
 
There's a diagram on the web with dimensions so you can check the pilot hole depth. Pretty sure it came from Brewer's.

I'm using a 78 360 in my car and it was drilled deep enough but I had already bought a Dakota bearing so I just went with that instead of driving in the bushing.

FWIW it seemed more difficult to get the input shaft shoved in far enough with the bearing than I remember it was for a bushing. Yes I used a splined alignment tool. If you run into difficulties, loosen the pressure plate bolts a little (equally on all) to let it move around a little so it all lines up and retorque after it's in.
 
There was a post here showing the correct position to weld on the frame ball stud for the z-bar. Maybe someone can chime in.
 
pntastar69 said:
There was a post here showing the correct position to weld on the frame ball stud for the z-bar. Maybe someone can chime in.
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I think hole is there on all cars, automatic cars had a rubber plug and stick cars had the bracket added. My car as the hole. Guess the rubber plug disappeared over the years. I just need to weld the bracket in place
 
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Uncle Bob said:
I bet it is. It's a factory, they don't want to be switching cranks for a common engine based on what transmission is behind it.
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After scouring the internet in dozens upon dozens of forum threads.. some have said they’ve never seen a small block that wasn’t, others have said that all pre-70 small blocks were drilled.. and some have said it’s a mixed bag..

The alignment tool I have is from brewers, it’s essentially an input shaft cut down to be used as an alignment tool so.. if that fits, I should be covered..
 
FlamesAreWicked said:
After scouring the internet in dozens upon dozens of forum threads.. some have said they’ve never seen a small block that wasn’t, others have said that all pre-70 small blocks were drilled.. and some have said it’s a mixed bag..

The alignment tool I have is from brewers, it’s essentially an input shaft cut down to be used as an alignment tool so.. if that fits, I should be covered..
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That's one way to do it I guess, but I don't know how you would know you are shoving it in the hole far enough. Too far doesn't really matter. I found the diagram:

1724269799801.png
 
FlamesAreWicked said:
I’m compiling a list of all parts needed to do a 4spd swap in my 68 Dart GT 318. It currently has a 904 automatic. I’m trying to cover all bases parts wise for when I go to do the swap (once the heat of summer time starts to drop some). The trans and clutch was sourced from a 71 Swinger with a 340

I just bought a big pile of parts from Brewer’s that arrives tomorrow that should cover the literal nuts and bolts of the swap.

Cast iron 23 spline A833 4spd with small block bell housing.

Shifter linkage and shifter

Clutch fork and boot

Mcloed street clutch disc, pressure plate, throw out bearing, and flywheel. The flywheel has been resurfaced and I picked up a new throw out bearing.

Z Bar with service kit from brewers (pivot balls, bushings, keepers, and hardware

Brewer’s pedal assembly

Rod from pedal to Z bar and firewall boot

Rod from Z bar to clutch fork

New steel floor hump

30 spline yoke for 7260 joint and new replacement joint

Shift boot and ring that mounts to the floor

Pivot ball bracket that’s welded to the frame rail

New ARP bolts for flywheel, pressure plate bolts, bell housing to engine, and from bell housing to trans

Speedo gear O ring kit to reuse the gear in the 904. I probably need a new Speedo cable too since my current is either stuck or broken

Lower dust shield that goes under the bell housing

Bell housing starter seal

Later model pilot roller bearing

I will need new carpet of course but as far as the installation goes, it’s not technically required. I will put new carpet and also replace the current old style starter with a later starter from a magnum engine. I’m also gonna go head and put a new trans mount since mine is 50+ years old.

Am I missing anything? Any help would be appreciated. I also have a new reprint copy of the 1968 service manual.

My main concern is the pilot depth may not be deep enough. It’s possible that it’s deep enough but not the right ID, that’s where the roller bearing comes in. I’m looking at the possibility that the input shaft may need to be shortened slightly. I did buy a Brewer’s clutch alignment tool that’s basically made from an input shaft. It wasn’t much more than the usual plastic ones. If that thing seats properly then theoretically the trans will too since it’s the same shaft essentially.

I plan to document it all and I’ll take as many photos of the process as I can.

As far as the adjustment rod for the clutch, is there a general starting point it needs to be adjusted to?

How long would the average two guys take that’s mechanically inclined to do this swap?

I’ll have to figure out the neutral safety switch and the reverse light indicator. If they aren’t a must to have it running and driving, I’ll add that after the fact. I’m really hoping my rear main isn’t leaking because if it is, I may just pull the engine and trans out in one unit so I can fix that while I’m at it.

Anyhow, I’m super stoked to finally see this dream come to be and I’m also a little intimidated about it out of the lack of experience of this specific job.
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Maybe buy a shifter kit with new spring clips and washers. Check for slop in the shifter. I had to install an extra plate in mine to have a firm shift. Took out of a part shifter. Note: I find I can shift quicker with the ball, instead of the pistol grip. If you want to change anyway, I would do it while the transmission is out of the car, to make it easier for the install.
 
Swinger 340 said:
Maybe buy a shifter kit with new spring clips and washers. Check for slop in the shifter. I had to install an extra plate in mine to have a firm shift. Took out of a part shifter. Note: I find I can shift quicker with the ball, instead of the pistol grip. If you want to change anyway, I would do it while the transmission is out of the car, to make it easier for the install.
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I ran it through the gears with the handle popped in.. it shifts really well. I love the look of the pistol grip but I also find the ball handle better for comfort.. with the prices of the pistol grip alone, I may just swap the shifter to the hurst competition shifter. Since mine has the bayonet style shifter, I’d need to swap that part alone to go to most any other handle. I did find an E body pistol grip that is the slip in style. It wouldn’t save me much money going that route. With the Hurst Comp, I’d kill two birds with one stone. I’d also have the freedom to experiment with different bolt on shift handles.

I suppose I could roadkill mod mine and just drill the holes to use a bolt on shifter but.. if I went with a hurst comp, I’d sell my stock OE hurst unit. Someone out there may be on the hunt for one..
 
Just curious if you bought the trans out of AZ? The pics look like a complete unit that was for sale out here recently and I didn’t pull the trigger on it soon enough before it was gone.

If you decide to sell the Hurst unit I’d be interested. Then I just need to find literally everything else. lol.

Anyone know if any 5.9 Magnums have drilled cranks? IIRC you could only get a manual in the trucks with a 5.2 and not a 5.9. Not sure if that was only 1/2 tons or not though.
 
JTinAZ said:
Just curious if you bought the trans out of AZ? The pics look like a complete unit that was for sale out here recently and I didn’t pull the trigger on it soon enough before it was gone.

If you decide to sell the Hurst unit I’d be interested. Then I just need to find literally everything else. lol.

Anyone know if any 5.9 Magnums have drilled cranks? IIRC you could only get a manual in the trucks with a 5.2 and not a 5.9. Not sure if that was only 1/2 tons or not though.
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I did..I bought it from Venom Classics in Mesa, AZ. I took the plunge since finding one locally wasn’t really an option. Shipping was reasonable and the trans came out of a rotisserie restored 71 Swinger. Their customer wanted to put an automatic in it. My 904 needs a rebuild so, rather than spending the money to rebuild that and the headache of pulling it for the rebuild.. I’d pull it and replace it with a 4spd. It was my plan anyhow when buying the car.. I’m just doing it first than other stuff first. I was gonna do brakes and rear axle upgrade. I’m still gonna do those things, just the order of which I do them was changed up.

I wanna say that the 5.9 was available maybe in a 3/4 ton with a 5spd? I’m not 100%. That’s the era that used the roller bearing that goes in the crank register. So long as the hole is deep enough for the input shaft, it’ll work.
 
I've got an untouched 5.9 that came out of a 98 3500 dually that was a straight drive truck. When I get home from the beach, I will try to remember to check it and report back. It's sitting on an engine cradle where I can get right to it, and compare it to my 273 that was factory drilled and has a pilot bushing already in it.

:thumbsup:
 
FlamesAreWicked said:
I did..I bought it from Venom Classics in Mesa, AZ. I took the plunge since finding one locally wasn’t really an option. Shipping was reasonable and the trans came out of a rotisserie restored 71 Swinger. Their customer wanted to put an automatic in it. My 904 needs a rebuild so, rather than spending the money to rebuild that and the headache of pulling it for the rebuild.. I’d pull it and replace it with a 4spd. It was my plan anyhow when buying the car.. I’m just doing it first than other stuff first. I was gonna do brakes and rear axle upgrade. I’m still gonna do those things, just the order of which I do them was changed up.

I wanna say that the 5.9 was available maybe in a 3/4 ton with a 5spd? I’m not 100%. That’s the era that used the roller bearing that goes in the crank register. So long as the hole is deep enough for the input shaft, it’ll work.
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Thanks for the info!
 
Maybe it was mentioned but I did not see it,,,, and having the motor out will make this easier, dial in the bell housing with the bell mounted and torqued to the block.
Manual transmissions are much more sensitive to alignment than automatic transmission are.
There are several sources for offset dowel pins if needed.
RobbMc has good ones.
And just because a crank bore is drilled to depth that does not mean it is honed to size for diameter. Ask me how I know that.
With a crank that did not have a bushing in the crank bore I will always carefully measure the diameter prior to pressing a new bushing in.
 
my68barracuda said:
Maybe it was mentioned but I did not see it,,,, and having the motor out will make this easier, dial in the bell housing with the bell mounted and torqued to the block.
Manual transmissions are much more sensitive to alignment than automatic transmission are.
There are several sources for offset dowel pins if needed.
RobbMc has good ones.
And just because a crank bore is drilled to depth that does not mean it is honed to size for diameter. Ask me how I know that.
With a crank that did not have a bushing in the crank bore I will always carefully measure the diameter prior to pressing a new bushing in.
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I’m gonna be using the later roller bearing. The clutch alignment tool that I bought from Brewers is just a repurposed 23 spline input shaft from a transmission.. I would think how that fits should give me an idea how well it’ll fit or it at all for that matter.

It’ll be a bit more work but I figure it would give me a good opportunity to deep clean and regasket the engine. It looks like it has had a valve cover leak on both sides for several years. I’m sure the gaskets are rock hard by now. They could have been changed but even if it has been done a couple of times through the years, it’s 56 years old so.. time to start fresh. I’d much rather try stab a trans outside of the car than under it. Hopefully it won’t open a can of worms that keeps the car down for months.. lol fingers crossed
 
I measured the depth of the pilot bushing hole in the 1998 5.9 Magnum and it is 2" 35/64 deep. This was measured with a straight edge across the OUTSIDE edge of the flywheel register as in the pic below. My 273, which has a 72 318 crank that was factory drilled measures exactly the same! I did not measure the diameter of either hole. I am guessing the roller pilot bearing is made for factory diameter of a Magnum motor. Hope this helps!
23395F26-D9DB-4364-8AA4-CF5780903F8F.jpeg
 
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JDMopar said:
I measured the depth of the pilot bushing hole in the 1998 5.9 Magnum and it is 2" 35/64 deep. This was measured with a straight edge across the OUTSIDE edge of the flywheel register as in the pic below. My 273, which has a 72 318 crank that was factory drilled measures exactly the same! I did not measure the diameter of either hole. I am guessing the roller pilot bearing is made for factory diameter of a Magnum motor. Hope this helps!View attachment 1716296140
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Great info, thanks! Now you wanna sell me that 5.9? Lol.
 
JDMopar said:
I'm hanging onto it for now. I'm sure you could find one close by to you for a lot less than what shipping would be on this one if I gave it to you for free....lol.

:thumbsup:
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What’s the usual going rate for one? I found one near me and they wanted 1200.. I dunno if that’s sky high or about the usual.. think it has 150k-ish miles
 
I would think you could pick up a core for a couple hundred bucks. Shop around and see how prices compare. I imagine it will depend on whether you want a known good motor or just a core to rebuild. Mine was a core I bought from a fellow FABO member who lives a few hours away.
 
This particular one was a known running engine pulled from a Ram pickup. My lil 318 seems to run pretty good but I plan to do probably a magnum 5.9 at some point. Hard to believe that the 5.7 hemi has been around 20 years now.. magnums are getting tougher to find..
 
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