T56 Magnum Conversion

[72bluNblu]

Nice work! I didn't realize you were doing the swap. Just a quick note, since your interior is out, install some heat barrier in. My Dart expels a lot of heat from the trans tunnel even with dynamat and a carpet.

Yeah, I've always had a quite warm floor before with the 4-speed. I remember leaving my phone on it before and I'd bet it was 110-120F, so maybe 30-40 degrees above ambient. I'll have to look into it. I'm not sure I'll have the interior all done this year since we have maybe 2-3 months before snow is a threat. Not sure how fast it will go from here on out since the mechanical work needs to be done, and I need to get a driveshaft on order.

Today I got the flash rust cleaned off the new metal, some grinding where needed, primer, seat reinforcement brackets welded in, Passenger seat bracket modified to fit correctly, and some unneeded holes in the floor welded up.

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Totally agree on the heat/sound barrier. It makes a big difference. I use FatMat RattleTrap, it's like a thicker version of the standard Dynamat stuff for a much nicer price. Works great! Not looking forward to peeling it up so I can do the tunnel work when I do my T56, but it won't be the worst part of the install.

Looks like you had the same ProCar adaptors that I got, I had to do the same thing with moving that tab on the passenger side. Annoying considering what you have to pay for the bracket to begin with.

Today was kind of a slow day, I applied the seam sealer, this stuff seems to be pretty nice (it's brush-on), however, the fumes are so bad I had to let it air out for the whole day and it had not fully cured in my opinion due to the high humidity so I didn't paint it today.

Once it aired out enough, I installed the pliot bushing. No issues with installing this even though its for an AMC application with a Chevy transmission.

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Nice!

The pilot bushings I bought was made by Hurst, it's a roller bearing with a custom surrounding adaptor for the end of the crank. Not sure it's available anymore, HurstDriveline totally changed their website and pulled a lot of their parts. That bushing seems like a good substitute, still haven't decided if I like the roller bearings in that particular spot. Might have to pick up one of those bushings to compare before I do the install.

 

[goldduster318]

DAMN!!!! That's awesome - I wish I had welding skills like that - One Day!!!
Keep up the good work!

The Millermatic 211 "autoset" feature helps a lot. Those seat brackets were literally the first 5/16" piece of material I'd ever welded in my life. I had to go manual setting for the butt-welding to get it right but it wasn't too far off from the "base" setting under the cover. This was the first big project I did with that welder, but it's a great machine, I really like it. It basically takes the guess work out of settings which is the issue a lot.

Totally agree on the heat/sound barrier. It makes a big difference. I use FatMat RattleTrap, it's like a thicker version of the standard Dynamat stuff for a much nicer price. Works great! Not looking forward to peeling it up so I can do the tunnel work when I do my T56, but it won't be the worst part of the install.

View attachment 1715225134

Looks like you had the same ProCar adaptors that I got, I had to do the same thing with moving that tab on the passenger side. Annoying considering what you have to pay for the bracket to begin with.



Nice!

The pilot bushings I bought was made by Hurst, it's a roller bearing with a custom surrounding adaptor for the end of the crank. Not sure it's available anymore, HurstDriveline totally changed their website and pulled a lot of their parts. That bushing seems like a good substitute, still haven't decided if I like the roller bearings in that particular spot. Might have to pick up one of those bushings to compare before I do the install.

Good tip on the heat/sound barrier. Just painted it tonight anyway (no photos).

Yes, they are the pro-car adapters. I honestly don't know how I had the bolts in that seat before but somehow they were.

I had read your topic trying to find the hurst bearing...and I ordered the wrong one apparently which was sized for a TKO (0.625 iirc), and months ago so I couldn't return it. These transmissions are far as I know are all 0.590 since they are GM input shafts. This is also a good deal for $33 or so delivered. These cars had bushings originally so I doubt its an issue being that it's oilite bronze.

 

[goldduster318]

Here's the paint:

I didn't have enough paint apparently to do the whole floor, but that's OK, I got all the spots I touched and also have the bottom painted up nicely in black (I use gloss because grease doesn't stick to it as well as flat)

The last couple of days after work, I've been working on installing the hydraulic clutch master cylinder. I'm not sure I have the firewall angle or inner fender hole right yet, so no pictures, but what they don't tell you is that the pedal ratio of the stock pedal is no where near enough for the clutch master cylinder. I had it all hooked up last night and there isn't near enough pedal travel. My calculations showed the pedal was 11.5" long -> and the pin was approx 2 5/8 from the pivot center, giving an approximately 4.3:1 pedal ratio. The clutch slave needs somewhere between 5.5:1 and 6.25:1 to have the correct travel and pedal modulation.

I cut the original piece off, welded on a piece of 1 1/4" x 1/4" bar stock lapped over the original and drilled a hole at approx 1.9" from the pin to get a 6:1 pedal ratio. I left everything on the other side for the down stop and also for the clutch interlock switch. We'll see how it works tomorrow, but it appears that the hole travels in a straight line about 1 1/8" which should be perfect. This has been a bit frustrating if I'm honest, even the bracket on the firewall needed grinding and I also had to tack weld it on there, which I would also recommend.

In other news, since it's not published anywhere, the shifter stub on the T56 Magnum is threaded 3/8-24. I also have my SST shift handle and white shift knob. Carpet should arrive tomorrow - I bought the ACC carpet with the heat/thermal backing so we'll see how that goes.

 

[goldduster318]

Okay, today, I finished the install on the master cylinder. The 6:1 pedal ratio change from the above post worked quite well. I did not use their rubber spacer that they provide, instead I used some washers. The play is non-existent in the linkage, and there is no rubbing or binding. I had to bend the clutch interlock switch bracket lightly so it wouldn't hit at full travel.

You can also see the cut in the wheelwell. This is a section that doesn't do much supporting (not welded at the bottom), I can install the AN fitting to the master cylinder with this installed, and later the hydraulic line.

Next on deck is dialing in the bellhousing using the Quicktime plate.

 

[goldduster318]

Today I worked on Dialing in the bellhousing, measuring for the driveshaft, wiring, and test fitting the shifter and boot.

I found that the 0.014 offset dowels I had were too much, I have ordered some 0.007 offset since that should get me in a good place easily. Below is a picture of the dial-in plate.

I also measured for the driveshaft and placed my order with Strange. The shaft should ship by Friday.

When I was wiring, I found that the connector is actually a Ford connector (Standard Motor Products S699), so I had to order one of those as well. I have my reverse lockout solenoid wired to the megasquirt through a relay and also the reverse lights fully wired.

The shifter is the SST offset shifter with a TwistedShifterz knob and the original style boot.

The X-pipe and everything (TTI 2.5" system) fits fine. I have to decide if I need to move my O2 sensor bung or not.

 

[Deceus]

Do mine next haha. Looks good, I really want to do this conversion as well but my CRT 904 is running good and this does NOT seem like a great first fabrication/welding project. I've done most of the work on my car so far but it's just been wrenching, this is definitely on a different level.

 

[goldduster318]

Do mine next haha. Looks good, I really want to do this conversion as well but my CRT 904 is running good and this does NOT seem like a great first fabrication/welding project. I've done most of the work on my car so far but it's just been wrenching, this is definitely on a different level.

Thanks man, yeah not a first project at all. If you felt pretty comfortable with a mig welder in general, and maybe did some level of sheet metal work before (I did some body panel patching on a couple vehicles with my friends), then it wouldn't be that big of a deal. You would absolutely need a 220V mig machine with gas (no flux core) as well.

I wish there would have been a little more info out there before I started, but that's the point of this topic. By the time its running, I'll have a realistic cost and what to do to pull it off, hopefully making it a bit easier!

I'm not sure you'd guess, but I have a desk job for my real gig! lol.

 

[goldduster318]

Got working on the carpet and interior. The front seats are in, carpet in (it doesn't fit perfectly, some lumpyness near the tunnel in spots but good enough I think).

The console is either going to need some modifications at the front or I will have to do something different.

I also got the 0.007 offset dowel pins and the VSS connector in the mail today. I wanted to finish the carpet before I started on that.

 

[goldduster318]

I worked on the bellhousing alignment today, with the 0.007 offset dowel pins, my total indicated runout was 0.004", so a really good measurement, so they are locked down now and I moved on to do the final install on the transmission. I got the flywheel all torqued, clutch with new GM 26 spline disk installed, and bellhousing back on. I still have to put all the bolts back in and the starter, and then it will be on to measuring the depth for the throwout bearing, setting the shims, and connecting the line to the master cylinder. At that point, the transmission can go in for good hopefully!

I also found out my driveshaft shipped from Strange so hopefully I'll see that in a few days as well.

 

[72bluNblu]

I worked on the bellhousing alignment today, with the 0.007 offset dowel pins, my total indicated runout was 0.004", so a really good measurement, so they are locked down now and I moved on to do the final install on the transmission. I got the flywheel all torqued, clutch with new GM 26 spline disk installed, and bellhousing back on. I still have to put all the bolts back in and the starter, and then it will be on to measuring the depth for the throwout bearing, setting the shims, and connecting the line to the master cylinder. At that point, the transmission can go in for good hopefully!

I also found out my driveshaft shipped from Strange so hopefully I'll see that in a few days as well.

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Nice!

Wanna sell your alignment plate?

What did you end up with for a driveshaft length?

 

[goldduster318]

Nice!

Wanna sell your alignment plate?

What did you end up with for a driveshaft length?

I think I'm keeping the alignment plate. You never know what you might need (or want) to do in the future. Same with the clutch alignment tool that I bought from RAM which is metal and seemed to be quite good.

The "A" length (back of transmission to center of U-joint) was 47 3/4". The paperwork said 44 7/8" c-c on the u-joints. Mine is the "Chevy" T56 Magnum, so if you have the Ford one, the bellhousing is shorter IIRC, and so is the input shaft on the transmission.

 

[72bluNblu]

I think I'm keeping the alignment plate. You never know what you might need (or want) to do in the future. Same with the clutch alignment tool that I bought from RAM which is metal and seemed to be quite good.

The "A" length (back of transmission to center of U-joint) was 47 3/4". The paperwork said 44 7/8" c-c on the u-joints. Mine is the "Chevy" T56 Magnum, so if you have the Ford one, the bellhousing is shorter IIRC, and so is the input shaft on the transmission.

I figured you would! I know I’d keep it, worth a shot though.

Thanks for the measurements! I have the “Chevy” length T56 magnum also and the same bellhousing. It should be pretty close, I’ll be measuring mine anyway but it’s nice to have another number to compare too.

 

[goldduster318]

Today I got the hydraulic clutch throwout bearing setup - apparently the kit I have wasn't drilled right to get the lines to go out the correct hole, so I had to drill and tap my own hole for the stud (didn't take photos), put the transmission in, bled the clutch slave, and continued to work on the interior.

 

[goldduster318]

Getting closer by the minute here. Today my driveshaft arrived from Strange (took about a week from the order), and so did my "Deluxe" Package tray with speaker cutouts from Classic Industries. I was able to put my 5-way pioneer speakers under the package tray by using some 1/2" speaker spacers. This makes it look pretty OEM. In any case, I have the interior all assembled and ready to go, the driveshaft installed, the speedometer re-calibrated (I have an adapter that threads on a speedometer takeoff that I ran with a drill), the VSS connected for good, and the transmission filled with Dexron III (it takes about 3 3/4 Qts). I still have to install the exhaust and test out the clutch action tomorrow before it goes on the ground.

 

[goldduster318]

Well today I finished putting it together and started it up. I'd say most things are OK, had an exhaust leak that was pretty bad at the ball flanges, got that fixed. The big issue currently is that when I release the starter, I get this horrible chirp/grinding sound, it seems to be gone once the engine starts. I tried loosening the bolts and pushing the starter over to no avail. Since this is a different spacer than what was on the block before, I'm wondering if its over-meshed into the flywheel and doesn't retract fast enough. The only other thing I could think of is the bendix may have gotten some grinding dust in it that needs to be cleaned out. I'd say otherwise it seems test drive ready.

 

[goldduster318]

I did get the shim, which I ordered from Ebay from Van's Auto. You will have to trim it some for the scattershield and the small block, but it fixed the problem with the starter rubbing. I took it around the block yesterday, most things seemed pretty good, so I washed all the dust/slag, etc off the car last night. Tonight I took it for a ride and I found that somehow I must have flipped the blocks inside of the pot coupler so the column has to come back out, and also no matter what the internet says, the transmission is 12 pulses/ rev on the VSS, not 17. I originally programmed it for 17 - and it was showing 37 mph when I was keeping up with traffic that was going 50ish. I already reprogrammed it to 12.

First impressions are...this thing really makes the car...and the car does better driving at low RPM than I originally expected. Runs fine at 1300 rpm in 6th. The transmission has way less gear noise than an A-833, so the car sounds significantly more refined.

 

[goldduster318]

And finally, the final tally and BOM:

Now, for most people, you have to remember that my car also had a manual transmission to start with so an auto conversion would need an entire clutch kit and pedals, but not the driver's floorpan patch. I also didn't deduct what I think I can get for my 4-speed - which will take some of a bite out of this.

 

[GoodysGotaCuda]

I may be interested in that bellhousing alignment plate, if you wanted to sell it?

When I bought, SST told me that my QT bell didn't need to be aligned. Tremec/SST have since changed that position.

 

[Deceus]

And finally, the final tally and BOM:
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Now, for most people, you have to remember that my car also had a manual transmission to start with so an auto conversion would need an entire clutch kit and pedals, but not the driver's floorpan patch. I also didn't deduct what I think I can get for my 4-speed - which will take some of a bite out of this.

 

[goldduster318]

I may be interested in that bellhousing alignment plate, if you wanted to sell it?

When I bought, SST told me that my QT bell didn't need to be aligned. Tremec/SST have since changed that position.

No I'm keeping it just incase something happens to the engine at some point. They're about $80 most places from what I remember though. It does need to be aligned. In my case, a lot of it may be due to the block being align bored.

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You gotta pay to play! At least I was honest. It will cost most people around $2500 to do a swap from auto to 4-speed though. We also live in the world where the MotorTrend Channel guys seem to use $4000 4-speed automatic transmissions like candy.

 

[Lil Demon]

Great write up! I'm in the shifter boot opening of my swap. I confirmed my idea by seeing what you did. Definitely am going to copy your setup. You may have mentioned so sorry as I skimmed over a few of the posts. How do you like the way the 6 speed drive and feels?

 

[goldduster318]

Great write up! I'm in the shifter boot opening of my swap. I confirmed my idea by seeing what you did. Definitely am going to copy your setup. You may have mentioned so sorry as I skimmed over a few of the posts. How do you like the way the 6 speed drive and feels?

First part would be I think perhaps having a more straight up and down shifter would be better, it feels a little far back compared to most manual cars, but I think I'm OK for now. The shifter boot doing it exactly like I did is a really tight fit to the transmission and also to the edges of the tunnel. I couldn't have spared a 1/4" on the pattern on the outside.

Otherwise, it's really great, car drives amazing, really makes it enjoyable to drive at speed (everything quieter, very smooth), shifts nice, didn't get a chance to put the break in miles on it to be able to rip it through the gears though.

The one thing is it does make some chattery type noises idling with the clutch out, but I believe this is normal for this transmission. The rest of the time, it's pretty much silent (way quieter than my A-833 when under load in a low gear). My case, the 2.97:1 1st was the right choice, and also so was the 0.63 OD.

 

[Lil Demon]

What exhaust system is that btw? Are you running catalytic converters?? I'm also going EFI but am considering using cats. Don't feel like having that fuel smell on my clothes.

 

[goldduster318]

Its the TTI 2.5" X-pipe system with the TTI full length step headers. I am not using catalytic converters. I would suggest NOT doing that, I think they will be too close to the floor and cook you to death. I also don't know how you could put them close enough for them to light off. It will still stink at cold start if it did before.

You won't smell like fuel unless you stand behind the car while it's warming up. This engine with the EFI and previously carb (and my previous 360 with magnum heads) ran pretty clean. If you're running the old school open chamber heads and/or a giant cam it might be a different story.

 

[Lil Demon]

Thanks for the advice. I am also running the TTi headers may just use that exhaust. Looks great!