Hydrive conversion/swap

[cbosman1]

I'm a newby on the forum and I'm restoring and updating a 1953 Plymouth Belvedere for my dad. My next project is to take out the hydrive and replace it with a GM 700R4 4 speed automatic that I already have (sorry, to all the purists out there, but it will make it easier for dad to drive.) Wilcap makes the conversion plate for it, but my question is, since the 218 flathead is set up for a hydrive can I just take out the tranny and plug the oil ports in the back or is there more to it? Has anybody out there taken out a hydrive and replaced it with something else? I know the oil pressure is very high because of the hydrive, and I would actually like to keep it that high if possible (40lbs at idle.) Also if anyone out there has put a 700R4 behind one of these engines I'd love to hear what it took and how it turned out. By the way, great forum! It's been an invaluable source for fixing up this car for my dad.

[John Burke]

A 350 turbo would be an easier swap. I have one behind my Desoto flat 6....With the 350 turbo you dont need the kickdown cable hooked up. All you need to do is run a vacumn line to the tranny and it will work just fine...With the 700R4 you will definatly need to rig up a kickdown linkage or you will burn up the trans. pronto...Just my $.02 worth...John Burke

[cbosman1]

Good advice. I have swapped in 700R4 before on other engines so I'm pretty sure I can rig up the throttle cable on the flathead. Did you use the Wilcap adapter for the 350 and if so how did it work?

I'm still curious if anyone out there has taken a hydrive off of a flathead and knows what I need to do regarding the oil system on the engine?

[PatS....]

Welcome to the forum. I'm pretty sure that you just have to plug off the supply to the trans on the engine. That was the only trans that needed oil from the engine, so the engine will be fine with those holes plugged off.

How about some pics of your project?

[cbosman1]

Here is the fun part of the whole thing. My dad's first car was a 53 Plymouth Belvedere he got for his 16th birthday. Ever since he sold the car (and the next guy totalled it,) he has wanted another one. So 53 years later I went searching and I found how hard of a car that is to locate. After months of searching I finally found the right car at the right price and it was only 4 hours from my house in California. We bought the car and surprised my dad with it for his 70th birthday! He just about fell over! He's like a little kid again anytime he drives it or talks about it. Since then I have been going through the car with my dad and updating everything because he wants a reliable daily driver. It has really been a great father son project. The car was originally from Nevada and is super clean with no rust! I bought it from a classic car dealer and he didn't know any history on it. There can't be to many of these in Nevada, anyone recognize it? The next project is the automatic tranny to make it easier for dad to drive every day. I've attached a couple of pictures.

Great forum, I've learned a ton about this car over the last few months of just looking at posts.

[John Burke]

Good advice. I have swapped in 700R4 before on other engines so I'm pretty sure I can rig up the throttle cable on the flathead. Did you use the Wilcap adapter for the 350 and if so how did it work?

I'm still curious if anyone out there has taken a hydrive off of a flathead and knows what I need to do regarding the oil system on the engine?

Yes I used a wilcap adaptor...remember I used it on a Desoto 6 that I put in my hot rod...so I did'nt have clearance issues

[PatS....]

Here is the fun part of the whole thing. My dad's first car was a 53 Plymouth Belvedere he got for his 16th birthday. Ever since he sold the car (and the next guy totalled it,) he has wanted another one. So 53 years later I went searching and I found how hard of a car that is to locate. After months of searching I finally found the right car at the right price and it was only 4 hours from my house in California. We bought the car and surprised my dad with it for his 70th birthday! He just about fell over! He's like a little kid again anytime he drives it or talks about it. Since then I have been going through the car with my dad and updating everything because he wants a reliable daily driver. It has really been a great father son project. The car was originally from Nevada and is super clean with no rust! I bought it from a classic car dealer and he didn't know any history on it. There can't be to many of these in Nevada, anyone recognize it? The next project is the automatic tranny to make it easier for dad to drive every day. I've attached a couple of pictures.

Great forum, I've learned a ton about this car over the last few months of just looking at posts.

That's a beauty! Factory carpet? Or is it a restoration? Talk about makin an older fella feel young again! I bet Dad's happy with this, it's just like new!

Just curious, what about the Hy-Drive makes it tough for Dad to drive? I've never driven one, just the M6 semi auto.

[greg g]

cap off the tranny feed, and half the amount of oil needed for and oil change.

[cbosman1]

Yep, he is really having fun with it. The hydrive isn't so bad once you get used to it, but the car seems to be geared pretty low, so the 4th gear and automatic will be nice for a daily driver. If it had been the overdrive model we probably would have left it.

No it's not factory carpet. Before I bought it someone repainted it, reupholstered the seats and put in a new headliner and carpet. Other than that the car is all original and really is a great driving car.

It's great to hear all we need to do is cap off the oil supply on the back of the engine. Thanks for the help.

[Normspeed]

Welcome to the forum. Great looking 53. I've always liked red/black paint schemes. Your dad must be on cloud 9.

Regarding oil pressure, a good tight flathead 6 will run 40 lbs, that's where the relief valve opens and bleeds off the excess pressure. If that motor is fresh, even 40 at idle is possible. Usually once they're fully warmed up they might drop off a bit from 40 at idle.

There are plenty of modified Mopars here so you aren't likely to catch flak from purists about the tranny swap. I can't think of a better reason to swap it than making it a better ride for your dad.

[cbosman1]

The motor sounds real tight and has great oil pressure, but I had low compression on #1 cylinder. So I took the motor apart to replace the #1 exhaust valve that was burnt. Much to my surprise it was still the standard bore with very little wear,but I threw a set or rings in it anyway. The con rod bearings also had very little wear, but I replaced them as well. Overall I was pleasantly surprised how little wear the engine had inside and that it had nerver been overhauled. It runs like a champ now.

With the help of this forum so far I've been able to: Rewire the whole car and convert it to 12volt, put disc brakes on all four corners (no power, but not really needed,) convert to electronic ignition, and install AC. The only two things left are the 4 speed automatic, and power steering.

After installing the AC, I'm tempted to switch to an electric puller fan. However, there is very little room between the water pump pulley and the radiator. Anyone have any advise regarding an electric fan to help with the potential extra heat from the AC and the AC condensor? Should I just keep the conventional fan and add a pusher instead, or is there a fan that will fit between the motor and the radiator?

[Don Coatney]

I am running a pusher fan only. I do not have air conditioning. Check my Photobucket link below (go to the radiator album) for pictures.

One of the reasons valves "burn" in these engines is incorrect valve adjustment. Better to lean on the loose side than to adjust them too tight.

[RobertKB]

Re the carpet. Your car is a Belvedere and they came with a carpet in the front and not the rubber floor map the other models had. I have a '53 Plymouth Belvedere 4-Door and it came with its original carpet. I have replaced it because it was very badly worn. Usually, the cars with the carpets have better floor boards as it was easier for the horse hair undercarpet to dry out rather than trapping water under the rubber. My floor still has most of the original paint on it and no major rust at all.

[cbosman1]

Don, thanks for the tip on the pusher fan. It was great to see your pictures, that was a part of the forum I didn't even know existed!

Robert, nice clean Belvedere. I love the colors. The original carpet thing would explain why my dad's floor board still looks so good.

Chuck

[RobertKB]

Thanks, Chuck, for the compliment. The colours are factory as the paint is original. Car has its share of gravel rash and a few minor scratches but they don't show in the picture. Incidentally, I really like the black and red on your dad's car!

[cbosman1]

That's amazing that it is the original paint still. This is the first time I've seen those rocker panel guards and they look great on the car. Have you ever run across anyone that is selling a pair? I would imagine those have to be extremely hard to find.

[RobertKB]

I do have a '54 Canadian Dodge parts car. The body is the same as a 53 and 54 Plymouth. I'm not sure if it still has those rocker mouldings or not and if so what condition they are in. They will look a little different than the '53 trim but should fit without any problem. If you want, I can go look, take measurements, and PM you. Let me know.

[cbosman1]

I'm interested. That would be great if you could take a look and a measurement and let me know. It's really hard to tell from that picture if it even has them. Thanks

I'm also looking for an extra crank pulley from a 218/230 (thin belt.) Any chance you have one from your parts car? I want to weld the pulley to my existing crank pulley for the AC. Right now I have the AC running off of a double waterpump pulley, it works great but I'm not real sure what that will eventually do to the water pump.

[RobertKB]

I did reply to your PM. Looking closer at the picture in the original format it does have the chrome on the driver's side but will have to check the passenger side and condition of both. I will PM or email you.