VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Rolling Chassis Upgrade 1937 MD

Last Sunday I took the 37 for a long drive and while mechanically everything went well, I was certainly the tortoise among many rabbits. Part of my drive required that I use the freeway and I started thinking about maybe upgrading the rolling Chassis to a more modern version, something from the 50’s or early 60’s. I’m looking at the second knee action rebuild, over heating in traffic, etc. I’m afraid if I don’t do something to make this car more practical I’m going to drive it less and less. I’ve had this car for over 50 years and she’s part of my DNA. Any thoughts?

Thrasher, if it was my car I would keep repairing it and stay off the freeway.

An option is to find and install a 3.73 gear set in the rear end. I can easily run 65 with my '38 Master.

I also agree, back in the day when the speed limit in Iowa was 70 mph on most highways that is how fast I drove my
37 Master with the 3.73 gears and I have had it over 80. I am not saying it was good for it but I did it and it is still alive today. It does have flat top aluminum pistons and insert rod bearings and a later model head other than that it is pretty stock.

I drive my 1950 at 65 to 70 MPH and get run over by all the modern traffic. Unless you get a car that can hold 80 MPH wou will be a turtle.
After I installed 3.73 gears drove the '39 at the same speeds and was a 100% dependable car.

Stay off the freeways and keep your sanity...........those nuts are all crazy with speed and tailgating and aggressive driving. Police don't do anything....guess they are out catching the drug dealers and rapists.

Good idea, would you give me some ideas where to start looking?

Hello Tharsher,

I have a '37 4dr. MD. I originally wanted to do what you are contemplating. Of course it costs money to make these up-grades so I drove the car as is, with the 4.22 rear gears and stayed away from the highways because of the fear of losing the engine. The original engine had been destroyed because the owner prior to my Uncle tried to keep up with today's speeds.
A guy I worked with mentioned this site and I learned about the Master having the "economy" 3.73 gear set. Further reading and I also found, to my disappointment, that 3.55's were not available for our rear differential and the cost of doing so was, at least for me, prohibitive.
Fast forward to today. I scored a 3.73 rear differential and trans from a guy in Pa. that was hot rodding his '37 2dr. sedan for all the same reasons you are considering.

I have driven my car to Franklin Lakes, New Jersey twice, once in 2017 and 2019. I have never driven my car faster than 60 mph. I have been given thumbs up, air high 5's and video of my car in the right lane cruising. Ever local highway here in Ma, and the surrounding states, drivers have allows given me plenty of room when they pass.

I have been to a variety of cruise nights and charity car shows. In everyone of them the fact that my car is still stock and it is a Chevrolet amazes people.

So I say to you, don't change history to fit the times, change the gears so that history is alive and in motion. Amaze the millennial with the simplicity of what we are entrusted to maintain so that the history of true paper and pencil engineering makes them wonder how it was possible without a computer or calculator.

We can only give you our opinions on why you shouldn't "modernize" your ride, but ultimately, it is up to you.

There is a way of upgrading the end of the driveshaft to use the 3:55 gear set that fits the 1940 to 54 rearend. It requires using the pinion socket from the newer driveshaft. I actually purchased those parts but I am not going to install them. I am going to retain the 4:22 gears in my 38. I intend to sell them and make some space in my parts storage area.

You’re right and your thoughts have helped me come to the same conclusion. I think there was some fear that if the engine gave out I would be stuck with a problem I could avoid by upgrading but in reality the upgrade would actually be a bigger problem. Thank you for keeping me on the the right path!

I agree, I would be doing the same thing when it came down to it.

Upgrade to a 3:73 if it is practical for you,

Keep in mind that if you are poking along at 50 mph in a modern car people who pass you may feel annoyed in having to do so. Those in the fast lane will not even notice more than a blur as they whip by.

I most stated the minimum is 50 MPH or even less. NC is 45. People will notice your old car, appreciate the fact that they were not designed to scoot along at 85 or so, and will understand. They are not offended except on back roads where a tour may be holding them up from safely passing.

If you can do the minimum then do so and do it on the interstate if you want to. It is not the problem as many suggest.

Best,

Charlie

It is not worth the extra work of adapting a 3.54 for a 1937-1939. There is only an 5% difference between a 3.73 and 3.55. At 60 MPH that is a 3 MPH difference.

Upgrading does seem to be it's own can of worms, after hearing from you and other members I`m going to stay with what works. Thanks!

You`re right, I`m overthinking what people are thinking.

I guess I initially thought about the 3:55 upgrade because it was available to buy new. Original 3:73 gears almost never turn up for sale, at least on Ebay and in local publications.

Thrasher,
I think you really need to step back and think about what you're shooting for (I think you've already done this...but commenting anyway)
You can spend a crap-ton of money and build an ICON derelict type car that can go 150 mph, starts first time because it has fuel injection, etc, but looks pretty much bone stock. Or you can work at having a car that is pretty much stock and go 55 mph like my great grandmother (Minnie Roberta Jones in Gilmer, TX) did. For me, each time I get in my 41 SD to go for a drive, I'm amazed that the car is running pretty much the same way it did almost 80 years ago. I plan to keep it that way for as long as I can. Like others have noted, I get tons of waves/thumbs up when I venture on the highways in the slow lane. I plan my outings with my old car so that I won't be sad if "Minnie" fails me.

Yep, I’m with you. I have a story to tell you…years ago I got the radio fixed after probably 30 years not working. As I turned it on for the first time it warmed up and without looking for a station Patsy Cline started singing, I felt like I was in the Twilight Zone! I’m all in for keeping it original and living the mystery!