Assembling the Engine/Trans as a Unit



When Ma Mopar assembled these cars on the line they installed the engine and transmission as a unit from underneath the chassis. I intend to do exactly the same thing so this update will show some of the special work that had to be done for this to happen.

Chrysler products mount the engine on a removable "cradle" which simply bolts to the chassis. This cradle is a pretty simple unit that also mounts the lower control arm, torsion bar front mount and strut rods as well as the steering box and idler arm. I'm not going to install all the ancillary parts at this time for a reason that will become evident later. Suffice to say that at this juncture just the engine will be installed on the cradle.

Before that happens I'm going to do a custom modification to the driver's side motor mount. Big block Mopars have historically had a problem with breaking driver's side mounts. Probably because even a slightly modified 383 or 440 can easily approach or exceed 500 foot pounds of torque. That in combination with a motor mount design that must have been done on a Monday by an engineer with a hangover creates a design that needs some help to function properly.

Back in the day a "torque strap" of one form or another would have been installed to keep the motor mount from pulling apart. The home grown way would have been a piece of chain in combination with a turnbuckle or even by itself. Today you can buy commercially available torque straps and specially engineered motor mounts from several aftermarket companies but they can be a little pricey. I am going to do an inexpensive mod that will solve the problem without spending a more than a couple bucks.




This is typically what happens. Above is the motor mount that came out of the car when the original 383 was removed. Below is a brand new unit.

The solution to this is to use some grade 8 hardware to pin the two halves of the motor mount together so they can't pull apart. This is not rocket science and is an easy job. This mount is not under compression when torque is applied, it is under expansion so the idea is to limit this expansion.




This is a 1/8" plate that has been drilled to fit the chassis side of the mount. That's the two bolt side. There are a couple extra holes drilled to accept two 3/8" grade 8 bolts as well. These are the holes at the corners.




Next the plate was fitted on the motor mount and two holes were drilled through the rubber and engine side plate to accommodate the additional bolts. Sorry I don't have any pictures of that... so shoot me. Once finished the plate was removed and two grade 8 bolts with their heads cut off were inserted into the holes and welded in place. I don't have any pictures of that either... sorry. The welds were then ground smooth on the chassis side so the mount will sit flat on the cradle. This is what you see in the above picture.




Here you can see the studs sticking through the engine side of the mount. Just a couple lock nuts needed to complete this job.




And here you see the finished mount (engine side) temporarily bolted to the cradle. Now you see why I think this design was done by an engineer with a hangover. It certainly could have been designed better, but with this mod the mount should last almost indefinitely.




The passenger's side is much simpler and needs no modifications at all.


With the motor mounts taken care of the engine was taken off the stand and mounted on the freshly painted cradle and the whole unit was set on a couple furniture dollies. Then a new flywheel, clutch, pressure plate and throw-out bearing were installed along with the bellhousing. I didn't include pictures of this because there was nothing out of the ordinary involved. It was a simple matter of just bolting everything together.

Before I could move on I had to open the A833 heavy duty 4 speed for inspection and below is exactly what you want to see when you open up a used transmission.



The original owner told me the trans had been rebuilt recently and he was telling the truth. Every syncro and gear were in perfect condition and there was absolutely no play in the input shaft. All that's needed is to button her back up and do a complete exterior cleaning of the trans and the factory Hurst shifter unit.




And with a little help from my better half the trans was mounted to the engine and this unit is basically ready to go in the car. That said there are several things I need to do in the engine compartment before that can happen so give me a while to get those things done.

I mentioned earlier that I was not going to add all the ancillary equipment to the cradle before installation. This is because once the engine and trans are in position I will use the engine hoist to lift them into position and there is no reason to add the extra weight at this time.

As you can see in the picture below I have removed the stock exhaust manifolds and installed a set of headers. These headers were the first thing I purchased for this car 15 years ago.




These are brand new Headman headers which have been sitting in the box for God knows how many years. I bought them off E-bay for a crisp $100 bill. They obviously need to be blasted before paint and that is one of the things that needs to be done before the engine and trans are installed.

You may wonder why I'm not going to have these coated. The reason is that ceramic coating wasn't done 53 years ago. Headers were painted plane and simple.




One thing about headers on a Mopar. Generally speaking you are going to have to "massage" them somewhere in order for them to fit properly. Now days they do make very good headers that need no dimples, but trust me they cost about 8 times what I paid for these, and my budget just wouldn't handle that large of a hit. Here you can see where a "dimple" was required to clear the mini starter. There were also a couple others needed here and there to clear spark plugs and torsion bars, but they all were relatively minor.





So here you have the completed unit. I really feel like I got a lot accomplished this month. Next month hopefully I'll get the engine and trans installed along with the master cylinder and all the engine compartment brake lines.



That's it for this month....check back often for more updates...





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