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I see a company that makes an adapter plate to mount a GM transmission behind a Packard 288, 327 or a 356 straight 8 engine. Anyone done this?? I would th8ink this would be a big improvement over the Ultramatic transmission, especially a 700R4 with lower first gear and overdrive up top.

John

If you mean Bendtsen's GM adapter, there have been some installs on V8s but AFAIK, only one that has been mentioned here on an inline 8. There may be others. The more common conversion has been to the Chrysler TorqueFlite. From the accounts of those who have given feedback, the GM conversion works quite well and may become more popular since it has been reported the people making the Chrysler adapter apparently stopped making them.

The V8 GM conversion requires few other changes but downside to the Bendtsen adapter for an inline 8 is the requirement for the modern small hi torque starter and 12v. Some have no issues with going to 12v -- particularly those who also want to add AC -- but others that would consider the transmission don't want to change other aspects of the car any more than the minimum and particularly don't want to mess with electrical.

That may be one reason more of the inline 8s have not been done but another reason is properly maintained and driven, the original 50-54 Ultramatics used with the inline 8s are much less troublesome than the late 54 Gearstart which transitioned into the V8 Twin Ultramatics. Behind the low torque, low HP inline 8s the Ultramatic is actually quite robust as long as it isn't driven like an indy car.

I was thinking more along the lines of improved gas mileage and relaxed rpms in overdrive for the long stroke straight 8 engines.
The early Ultramatic was pretty trouble free.

John

I got mine from speed gems if I remener right it was around $900 maybe less its been about 4 years since I bought it and it is the plate mini high torque starter and flywheel. I didn't do the 700r4 I went with a standard trans, because I didn't want to mess around with trying to figure out the kick down cable. The guy is in Minn if my memery is correct and he makes them there in his tranny shop you give him any motor and trans that you want to meet up and he'll make it. His site istransmissionadapters.com/

Although the Chrysler crowd waxes and croons about the 727 Torqueflite, I think the Borg-Warner 3 speed was a better unit.

The 700R4 is a superior choice to the TorqueFlite except for the cussed 12 volt conversion which I detest.

However, you can still buy the old 6-12 dual voltage battery that will run the starter on twelve and the car on six. That makes the 700R4 a drop in as long as you can still get batteries. If they come empty then buy three for the next 21 years.

The only thing that makes Ultramamtic attractive is that, if not abused, it does hold up very well.

I attended a Hamlin presentation on the 727 conversion and he said it made a dramatic difference in straight 8 cars. And I don't think the Packard 8 is powerful enough to stress the TorqueFlite either so it should be even more reliable than the Ultramatic.

I would never attempt conversion without gaining an overdrive on any hiway vehicle expected to run over 50 mph.

Hi I did a Chrysler 518 od trans behind my 327 thunderbolt with a 288 head
Today's the first day it's been running
Ok major headaches ,wish I'd stuck with the ultramatic but I'm in it now
Challenges ,it's longer than the stubby ultramatic
Cso you not only have to shorten the shaft ( easy) but you have to tunnel the x brace ( tough) plus putting the motor trans in and out of the car with a thing that long is tough
Then you have switch issues
The 518 has 2 switches a ODD and a torque converter lock up these are 12 v - gr and your car is 6 v pos gr they are run by hydrolic pressure at two taps on the tyranny
also there is a vacuum switch
You also have to make the hump higher
I did all of this
Today first run the car didn't know what gear to go in and over heated
Oh well
I had a module that isolated itself and supplied 12 v neg to the tyranny and kept all of my pos gr 6v stuff ,it was really hot today so I guess it's shorted out ,also the vacuum is off of a carb port and may not have been strong enough to do the switch
I may go 12 v to fix this do I have to get a new starter?

I have a Bendtsen adapter to put a GM 700R4 transmission on my 356 engine. I have not driven it yet but the adapter is a work of art. I've converted to 12 V since I want an Air Conditioner and an XM radio.

I've fabricated an engine rear mount as the 700R4 only has a rear mount and I think the aluminum transmission case might be a bit over-stressed at its front flange.

You can run your original starter on 12 volts but you might want to have it 'converted' to 12 v to ensure its life.

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It might be wise to investigate converting the starter. In the last year there were several reports within a fairly short timespan of cracked and broken starter end castings. Different models, years and reports from different countries. The only thing in common was all were running 12v on the original 6v starter. Best guess is the increased speed and torque provided by the 12v was slamming the pinion into the end housing with enough force to break the cast iron.

Hi Im a happy convertee ,I have a chrysler 518-a behind the mighty thunderbolt ,,so its the 727 thats got an overdrive and torque converter lock, up that 727 users would convert to ,
theres a great how to by a company called PATC easily spotted on google

boy right about 62 you can feel it slip into overdrive i can go 70 at 1700 rpm!
it pops out back down if you go over an overpass or accelerate but settles back in after ,nice ,
on my 6-12 I just got a bolt in powergen AND A PERTRONIX 12 V POINT REPLACEMENT and went plug and play .i havent blown the starter yet but the headlights went without warning right away so im putting in 12 v bulbs and got a resister on ebay for the 6v tube radio
maby ill get a starter and have it rewound to have around for when the peppy 6 now12 v starter destroys itself ,right now all i have to do is look at the key and the thing starts !
I have a rebuild on the thunderbolt so the engine is stiff now ,we;l see how she feels after break in .
I also had gone for the 2 bbl to the 4 bbl 1951 option ,which was a big help going up hills ,but lusting for raw power , now have a dual 2 bbl intake on the car with the 288 head for compression jump
a dual exhaust would be a nice touch ,I heard legends about a dodge ram exhaust manifold that could be jimmied on with a little flange grinding
i should be gt od as long as we can get gas,maybe someone will come up with a nuclear steam engine attachment ,we have put probes on venus after all
getting front discs is a good nod if your freeway cruising especially if any city type drivers on the road with you