42RH / A-500 in a Duster with pictures.

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Yep my bolt circle measures 10.0" so I should be good with the ATP Z196. Specs say that one is a 10.0" bolt circle as well. Incidentally that part number goes all the way back to 1967 on 273 and 318. Heres pix of that V6 plate with hall effect trigger ring. Notice all the punched out holes on one side for balancing. I am showing this pic so people know not to use this one on a neutral balance V8

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So there was a u shape machined into the bellhousing on my 42RH for the hall effect pickup that gets triggered by the old flexplate I dont intend to use. What did everybody do to theirs. I figure tight welding a piece will warp things a bit. What about filling it in with JB weld just to get rid of the cut out? What has everybody else done. I know JB in there wont have a bunch of strength. It was more for aesthetics to get rid of the cut out.
 
So, what has everybody else done about this flywheel sensor cut out in the bellhousing?? Did you leave it, have it welded up, or JB Weld fill it.

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I would make a 1/8" thick piece of metal in a shape that completely covers the hole and either epoxy it in place or drill and tap a couple of holes to screw it to the housing. That way you don't get oil slinging all over the place as the seals wear. The screw holes don't have to be very deep since the screws don't have to hold much.
 
I am in the process of rebuilding ta 46RH myself, going into my 1968 Barracuda. How many degrees are you guys running the transmission/driveshaft at? This is all I had to cut out, an no massaging to get in there.

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Will be doing this very mod with a 42RH in a 69 barracuda. If I can suggest, you probably need to strap the cutout to box it in. I am going to use 1/8" steel flat stock bent into a horseshoe shape. Mine will probably be easier to weld in since I plan on modding the crossmember when I have the floor pan out for replacement.

As far as the down angle on the trans. Your carburetor mating flange on your intake should sit level. If you notice, intake manifolds have a slightly wedge shape from front to back because the driveline angles down and yet the carb sits level.

My recommendation is level the car front to rear on jacks with bubble levels taped to the doors rocker panels with the aluminum sill plates removed. With the car leveled, then remove your carburetor, and tape a bubble level to the carb flange on your intake manifold. Now set the angle of the drivetrain where the bubble on the carb flange is level. Now build your mount to that height.

If I am wrong here, please someone step up and provide other information since this was how I was going to go about it with the trans crossmember mount I will be making.

Hope this helps
Matt
 
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I have a 3/16" piece of flat steel that I bent into place to fit the cut out. I just did not take a pic at that time. But yes, that is in the plan before I build the crossmember.
My engine is set at where it was from factory, I am just curious of how many degrees down the driveshaft is to make sure that the Ujoint needle bearings function properly to eliminate any issues there.
 
If the engine is set where it was angled at from the factory, then go with it. The more critical angle is on the rear axle itself. That's where the most degree of movement is going to come from and will be exerted on the rear u joint anyways. If you havent messed with the rear axle pinion angle, I would say wherever the trans is at with the engine at its stock angle is fine.

Since I have no drivetrain in the 69. I will mock it up the way I mentioned in my last post.
 
What's the thread size of the 4 torque converter to flex plate bolts used on the 42RH ? I'm at work, and want to load ARPs up in my summit shopping cart at lunch break. Already have the crankshaft to flex plate bolts loaded up in my cart.
 
That 3/16" might be a better way to go actually. I have both that and 1/8" in sheet form in my shop. jrlegacy23 , are you planning on just eliminating the inner 2 bolts for the crossmember, or moving them outward and relocating them. They definitely need to be chopped out of there to get the trans to fit since it is quite wide. Heres what somebody else did in pix below, which I will probably copy.

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moparmat2000 said:
That 3/16" might be a better way to go actually. I have both that and 1/8" in sheet form in my shop. jrlegacy23 , are you planning on just eliminating the inner 2 bolts for the crossmember, or moving them outward and relocating them. They definitely need to be chopped out of there to get the trans to fit since it is quite wide. Heres what somebody else did in pix below, which I will probably copy.
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I plan on the same, those are some nice pics for reference. I figure that if the factory wanted 4 bolts, so do I. I did eliminate the inner 2 bolts, but the passengers side looks like it has enough clearance to weld the stock one back in and use it without issue
 
I thought so too on the pix, which is why I copied them into my phone. I have one folder in my gallery labelled 42-46RH install. Whenever I come across pix of how different fabo members tackled this trans install with an idea I like, I make a copy of whatever it is and archive it.
 
Hi gang. Would this wiring scheme work and protect my solenoids and vacuum switch using a Bosch relay?

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I cannot really read your diagram as it's too small and too dark but in a word, "no." The way the solenoids work, is that power is applied to one terminal not through a switch, but powered with ignition. Then whatever function you want, either OD or lockup, is activated by a switch or relay which GROUNDS one of the other two terminals.
 
Thanks. I should redraw this I think. No wonder it looks incomplete. I left out the Hobbs pressure switches on the od & lu ground triggered by the governor pressure. I already deleted an earlier post today with a drawing that didn’t make any sense at all after I really looked at it. Back to the drawing board.
 
jrlegacy23 said:
Should be easy enough to add a second switch with the same concept
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Anyone have a part number for a 80" speedo cable? Just ordered one correct length but the thread on connector at the trans is way to small.
Thanks
 
gdonovan said:
This thread is for detailing the install of a 42RH or A-500 in an A-Body. This should also apply to either an A-518 or 46RH as well since they have the same overdrive unit as a 42RH.

IIRC the Dakota RT manifolds are 2 1/8

The car in question is a 1974 Duster with a late model 1994 5.9 with Enginequest heads, CompCams .510 roller & Edelbrock RPM intake. The car currently has 318 manifolds which are going in the trash since I had to cut off the front section of the dual exhaust and H-pipe anyways. The manifolds will be replaced with a '73 340 manifold on the drivers side and a early magnum Dakota manifold on the passenger side with 2.5 inch outlet.

The purpose of the 42RH swap is to improve the launch of the car (2.74 first gear vs 2.45 in the 904 and better converter,) improved mpg (1900 rpm at cruise vs 3500 rpm,) higher top speed and less cabin noise at speed due to the lower operating rpm.

The 42RH is pretty much just a slightly newer version of the A-500 from a local yard (1994 Dakota 3.9 application in this case) It had a 4/4 clutch setup which will be updated to a 5 clutch setup with either a different drum or thinner steels.

Pictures and more details will proceed this post! Gary

PS: Please do not inquire in this thread about weakness or strengths of the 42RH / A-500, transmission upgrades or how it will be shifted into overdrive and lockup. The narrow focus of this thread is how to install one in a car, period.

Trans upgrades and shifting of the overdrive unit and lockup will be covered in their own threads and I'll request moderators to remove any non thread related posts so things remain concise and to the point for your reading pleasure

Thanks!
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moparmat2000 said:
That 3/16" might be a better way to go actually. I have both that and 1/8" in sheet form in my shop. jrlegacy23 , are you planning on just eliminating the inner 2 bolts for the crossmember, or moving them outward and relocating them. They definitely need to be chopped out of there to get the trans to fit since it is quite wide. Heres what somebody else did in pix below, which I will probably copy.

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That looks a lot like this one. I'm putting an A-500 in my 67 Barracuda. If I use this transmission mount will I still have to cut the tunnel and reweld a u shaped plate in it's place? Have you or anyone else used these transmission crossmembers?

518 Crossmember Kit - 67-75 Dodge Plymouth A-Body 1967 Plymouth Barracuda Transmission Crossmembers | X-Parts X395-1067-3 (autometaldirect.com)
 
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