Any feedback on a 518 in a Fusey?

I know the 518 is the way I'm going. I already have the transmission and a JW Ultrabell so that is non-negotiable.

What I'm wondering is what kind of fitment issues have been found when installing the transmission in a 69-73 barge?

My 72 Imperial is meant to be a road trip machine and I've already driven it form Dallas to Detroit. It's an awesome ride but I wanted to drop the RPM.

The 440 is currently out so I can go through it with an eye on low to mid rpm torque. The rear is carrying a 3.23 TrueTrac and the car wears 255/70-15 tires that are 29" tall. Toss in the OD and this should become one of the greatest road trip cruisers of all time.

Anyway, have you guys done this swap and if so what problems did you encounter?
Any updates on swap?
 
Any updates on swap?

Nope!

I tend to dig into things and get stuff laid out well in advance. That really helps when it comes time to do the work.
The motor is still apart at this time.
 
I would keep my 727 someplace handy. The A518 in question was designed for a relatively low torque small block engine (based on the small block 727 or 904 transmission). I think it will be unlikely to live very long behind a high torque big block pushing around a 4000lb car. Let us know how this conversion works out. Hot Rod magazine did an article on this conversion a while back. You will need to fabricate a new rear cross member and cut out part of the drive line tunnel and fabricate a new one. Drive line will need to be modified to fit the longer transmission. Article is at:
www.hotrod.com/articles/43323-mopar-overdrive-transmission-swap/

Dave
Dont think a 518 can handle a 4k lb car? Ever put a 92 Dakota on a scale? Mine is 4100 lbs.
 
Dont think a 518 can handle a 4k lb car? Ever put a 92 Dakota on a scale? Mine is 4100 lbs.

Right about the weight, most likely your Dakota has a 318 small block putting out something like 250lbs of torque. A 440 of that vintage is in the area of 375-400 lbs of torque. With some ignition tweaking and an aftermarket carb, this number will jump to the 450 range or higher. The 518 was designed for a small block. Still think it will be iffy behind a big block because of the high torque differential. Good potential to smoke the clutch packs or break an input shaft. Anyway, his car his money, hopefully he will report back on how it worked.

Dave
 
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What tranny do you think is behind all these 390 and 408 strokers?
The stock 318 is 230 hp and 310 lb/ft torque and lived behind 360s. Its a 727 with OD in the tailshaft. More than capable.
 
They used them for a long time until they built something better. What's the main difference between the 46 and the 47 used behind the Diesel's? The 46rh/re is the 518
 
The thing I'd be concerned with is the sub-2300rpm power. On many current vehicles, that's where things are in OD at 70mph cruise. Then how easily it would be to get a kickdown into direct for hills and such. AND how the manifold vacuum levels were at these rpms and such. At which degree of "grade" would it be best to downshift into direct to keep the manifold vac up so the fuel system did not go into the enrichment phase of things.

To me, IF the governors and pressure switches are correctly matched/calibrated, then manual over-ride would be minimal. Keeping it locked in OD might result in lower vac levels and then get into the fuel enrichment situation, which is not the best for fuel economy. Not that the engine would not pull OD in those situations, but at what level of intake manifold vacuum?

It's going to take some "on the road" testing and recalibration, I suspect, to get things dialed-in.

As for dyno curves, Comp Cams has a neat program for predicting those.

Enjoy!
CBODY67
There is now dash mounted electronic module available that you can program to control convertor lockup and other features. Have not actually seen one installed yet, so I do not know if the darn thing actually works or not. Be nice if it did. Available at www.hgmelectronics.com.

Dave
 
Dont think a 518 can handle a 4k lb car? Ever put a 92 Dakota on a scale? Mine is 4100 lbs.
Actually these Imperial's weighed in at closer to 5k.
If you're looking to get great fuel mileage with a 73 Imperial, you shouldn't even be owning one of these.
You're throwing good money away. The money your wasting on all this bs, could be spent on recovering the front seats or a paint job, re chroming the bumpers whatever.
What are you going to gain? An increase of 1.5 mpg? Lol You can buy a lot of gas with the money your going to waste on this project.
You said yourself,
My car is nothing to look at. It's just a big old barge badly in need of paint
Spend your hard earned cash on making it look good and never mind the rest of this nonsense. IMHO
 
As a California car, this thing was equipped with a factory electric fuel pump. There was a rubber fuel line coming out of the tank, over the axle hump, and attaching to the fuel pump. The pressure line went from the pump back over the axle hump and connected to the same fuel line used on all the cars. There was an oil pressure switch that would turn off the pump if the engine died (collision, rollover, etc).
This was all done because the only place to put the smog pump was on the lower right side of the engine and it blocked the mechanical fuel pump mount.

I've never heard of a factory installed electric fuel pump. I think someone put that in there. I just looked it up and the FSM clearly shows the air pump on the CA Imperials was under the power steering pump on the driver side.
 
Actually these Imperial's weighed in at closer to 5k.
If you're looking to get great fuel mileage with a 73 Imperial, you shouldn't even be owning one of these.
You're throwing good money away. The money your wasting on all this bs, could be spent on recovering the front seats or a paint job, re chroming the bumpers whatever.
What are you going to gain? An increase of 1.5 mpg? Lol You can buy a lot of gas with the money your going to waste on this project.
You said yourself,

Spend your hard earned cash on making it look good and never mind the rest of this nonsense. IMHO

In addition to what has already been spent on the adapter, you are looking at about $2000 to $2500 for a rebuilt transmission, and another roughly $1000 to make the rear transmission mount, shorten the drive line and fabricate any necessary linkage parts. If your going to use an electronic 518, you are going to need an after market control. Figure on another $250 to $500 for that by the time you get someone to set it up. This has the potential to be a real money pit.

Dave
 
I've never heard of a factory installed electric fuel pump. I think someone put that in there. I just looked it up and the FSM clearly shows the air pump on the CA Imperials was under the power steering pump on the driver side.

I'd never heard of those Imperials having or NEEDING an electric fuel pump, either. Even after I validated it was possible, I then suspected it had to do something with fuel handling on CA-spec vehicles. BUT when I looked in the parts book, the Imperial ONLY in that ONE year had something mounted under the alternator that was right smack where the fuel pump would have otherwise been. Factory block-off plate included. Not sure what they were trying to accomplish or why, but it was there in the parts illustrations.

As much as we tend to rely upon the FSM for information, the reality is that they are edited in June or July prior to vehicle introduction. I've noticed that, in some cases, the pictures/illustrations can be for the prior model year and don't exactly match what actually went into production. It gets even worse with some of the Chilton manuals, by observation, which are more "representative" than "exact". The particular editors might not have been aware that Imperials would have a different set-up than regular Chryslers?

On the other hand, for that special (low-production) Imperial situation, getting those unique parts orchestrated for the Imperial applications probably had to have the specs/bids approved even earlier in the 1972 calendar year! Especially when considering getting the vehicle assembly manual printed. Lots of lead time can end up being a part of that total equation.

CBODY67
 
In addition to what has already been spent on the adapter, you are looking at about $2000 to $2500 for a rebuilt transmission, and another roughly $1000 to make the rear transmission mount, shorten the drive line and fabricate any necessary linkage parts. If your going to use an electronic 518, you are going to need an after market control. Figure on another $250 to $500 for that by the time you get someone to set it up. This has the potential to be a real money pit.

Dave
Cant count everything with money. If would do so, we should crush these cars to tuna cans and buy smallest Toyota, Huyndai etc... that would be best for money wise.
 
Since we are somewhat off-topic now anyway, who would care to take a stab at a 518 problem?

Started out as late upshift in my 5.9/518 Mexican Ramcharger. Experience and the innernets say to adjust the Throttle Valve (TV) cable, aka kickdown linkage. Late shifts mean add slack to cable.

After doing that, and a slight over-topping with ATF+4, I'm now having a flash/overrun shift (I think the 2-3, haven't driven it in a while). As soon as I felt it, I stopped driving it. (Also, road salt.)

The over-topoff would be less than a quart, since it was slightly down and I added what I thought was less than a quart. (poured from larger container)

Or I may have added too much slack? But the adjustment range was very small. Haven't had this before on any TF, but this is the 1st 518 I've ever adjusted.

Thoughts? Haven't re-adj yet because

IMG_20171213_150427.jpg
 
Someone has a lot of balls to suggest I don't know how my car was built despite the fact that I'm the one who has gone through the engine and fuel system.

The smog pump was UNDER THE ALTERNATOR ON THE IMPERIAL. It blocked the fuel pump. Would you be happier if I showed you the mounting brackets and pump block off plate?

Yes, I will be putting an OD in my car to help with economy AND engine wear. Mostly, it is for peace of mind when I'm on road trips.
Why? It is MY CAR and I will build it how I want.

Yes, the Imp tops 5100 lbs. Yes, the 518 will survive JUST FINE behind the 440. The transmission in my 1992 D250 is a 518 with minor differences (yes, 618) but it has survived 299,600 miles so far. That includes abusing the 5800 lb diesel doing donuts, going airborne, off roading, and towing in overdrive.

Guess what? The gasser 518 I have is built just like my 618. The only differences are the bellhousing bolt pattern and the governor weight.
How do I know? I've been into the truck's tranny to replace a seal for the OD and I've torn down the gasser transmission.

Amazing bunch of keyboard jockeys around here. I didn't think the "I know better than you" Moparts crowd hung out here.
 
In addition to what has already been spent on the adapter, you are looking at about $2000 to $2500 for a rebuilt transmission, and another roughly $1000 to make the rear transmission mount, shorten the drive line and fabricate any necessary linkage parts. If your going to use an electronic 518, you are going to need an after market control. Figure on another $250 to $500 for that by the time you get someone to set it up. This has the potential to be a real money pit.

The transmission was free.
The adapter was $300 about 10 years ago and I still have it.
I build my own transmissions for a few hundred bucks.

Fabricate parts? That's what my home based machine shop is for. I fabricate things.

All told, I'll be into the OD for about $1k after I pick up the converter I want.

You never get your money back out of an old car like this. Instead, you build it to be what you want it to be. What makes me happy is likely different than what makes you happy.
 
The transmission was free.
The adapter was $300 about 10 years ago and I still have it.
I build my own transmissions for a few hundred bucks.

Fabricate parts? That's what my home based machine shop is for. I fabricate things.

All told, I'll be into the OD for about $1k after I pick up the converter I want.

You never get your money back out of an old car like this. Instead, you build it to be what you want it to be. What makes me happy is likely different than what makes you happy.


Very well put

Dave
 
I hate to do this, but f-it I get yelled at for more stupid stuff. Carmine your TV cable is sticking/sluggish the lever may be gunked up also. There is a spring that connects TV cable and to the lever check to see it is not streched because of fouled lever. Basically clean everything on trans end, should get rid of early downshift to 2nd. Make sure to readjust when clean and correct to keep 2-3 upshift crisp.
 
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The transmission was free.
The adapter was $300 about 10 years ago and I still have it.
I build my own transmissions for a few hundred bucks.

Fabricate parts? That's what my home based machine shop is for. I fabricate things.

All told, I'll be into the OD for about $1k after I pick up the converter I want.

You never get your money back out of an old car like this. Instead, you build it to be what you want it to be. What makes me happy is likely different than what makes you happy.

For whatever it is worth, I would go with the heaviest duty convertor I could find. We worked on a lot of fleet carry vans/cube vans with this transmission. They were mostly in rental fleets and lead a tough life due to lack of service, abusive drivers, overloading and in some cases a lack of adequate routine servicing.. The transmission failures usually started with the friction material in the torque convertors breaking down and clogging the filter. Once the filter was partially clogged, the oil pressure to the transmission dropped. This caused the friction components to slip and eventually fail. Loose friction material is also highly abrasive and it does a number on the hard parts in the transmission which is one of the reasons commercial rebuilds are so expensive. My 2 cents.

Dave
 
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The transmission failures usually started with the friction material in the torque convertors breaking down and clogging the filter. Once the filter was partially clogged, the oil pressure to the transmission dropped. This cause the friction components to slip and eventually fail.

Holy cow!

Someone else knows why the 518 got such a bad rap for having a "weak" OD?
Everyone is quick to bash the transmission but so few know that the converter clutch is the blame.

I do plan on using a lock up converter and have a substantial transmission cooler. I've been checking with the diesel boys to see which ones they prefer for stock-ish trucks. Those things make the same torque the Imp will and tend to haul far heavier loads. Something like that should work fine for my application.

I believe in keeping a transmission cool. My truck even has the "super cooler" package with the fan mounted cooler under the bed to help keep it cool under load.
 
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