Newbee 1939 question

[30-9]

Hi I'm new to this site and already am very impressed with, not only the site but the wealth of knowledge and the family type support. Kudos from the new kid on the block.

I recently purchased a stock 1939 Deluxe. I was told by the Owner that for highway driving I shouldn't exceed 50-55 mph. He stated that while the engine is fine for higher speeds the rear is not. This is not a major issue as I'm not a speed demon. But would like to know - Is this true?

[Vic Piano]

That would depend largely on the rear end ratio. If the car is equipped with a 4.11 rear, highway speeds of 55 are attainable but extended driving at that speed could tax the engine. If the car has a 3.78, highway speeds above 55 mph (for extended time)are easily attainable. That said, you should check out the suspension, brakes, etc. before you venture out, even to just drive around the block. I would also suggest that you check the fluid levels in the crankcase, transmission, rear end and steering box, before you do any real driving. Have fun with your '39, by the way, what body style is it?

[30-9]

Vic thanks it's a Deluxe

How can I tell what rear 3.78 or 4.11?

[jake197000]

I agree if the engine is strong,as in not worn out.

[JSeery]

I agree with Vic, I think the engine would be more of a concern than the rear end. These rears were used in racing applications for years and still are with some quick change setups. Don't think it was the RPMs that got them most of the time it was the horsepower/torque. The weak part is the tapper at the ends of the axles and some claim with the proper prep even the tapper will take a lot.

[4dFord/SC]

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Originally Posted by 30-9

Vic thanks it's a Deluxe

How can I tell what rear 3.78 or 4.11?

Here's an article that explains the procedure: http://www.btc-bci.com/~billben/reargear.htm

FYI, you'll find a wealth of flathead technical information on that same site.

[Vic Piano]

What I meant with my question was; what body style, i.e., Coupe, Tudor/ForDor Sedan, etc. Have fun with the car.

[30-9]

Oh sorry - Coupe

[rheltzel]

30-9, I think the old owner of your car was being hopelessly conservative. I routinely drove my '37 pickup which had a 3.78 rear end at 65 - 70 all day long. I must not have hurt it, as it was still going strong when I sold it, after putting 75,000 miles on the engine. I now have a '35 with its original engine (rebuilt about 8,000 miles ago) and I drive it at 60 to 65 almost every day. If your rear end isn't making any funny noises, I wouldn't hesitate to drive it at faster speeds. As to the engine, if it's otherwise sound, i.e., doesn't overheat, isn't making any terminal death noises (e.g. knocking bearings), I wouldn't hesitate to drive it continuously at 60 - 65. Flathead Ford V8's were (and still are) extremely robust engines.

[PeterC]

Agree with Vic but will emphasize that while the 39 hydraulic brakes are very good for 1939 traffic - they cannot compete with modern cars and erradic and crazy driving styles you will share the road with ... so driving at 55 is fine - its stopping on a dime that will be the challange - no matter how pefect your brakes are - big car, skinny tires, instant stop - not good .... just friendly caution to keep in mind.

[Vic Piano]

PeterC is right about the lockheed brakes on the '39 Ford, they can be a PITA to adjust and keep in adjustment. As you gain more driving experience with your '39 Coupe, you'll come to understand, and appreciate, the idiosyncrasies' that make the car an adventure to drive within its limitations. I'm sure you'll enjoy it, I love driving our '39 CS, and I drive it everywhere.

[30-9]

thanks folks some great advise!

[adileo]

Hi - I'm curious what rear was typically put in a 39 deluxe coupe? They actually had two options?

[rheltzel]

It was probably pretty evenly split between 4.11's and 3.78's. There was also a 3.54 ratio. There were even numerically lower rations for special applications like high speed police patrol vehicles. I have a 3.54 in my '35. Pro: it's very happy at freeway speeds; con: it's a little sluggish around town because of the tall gearing. My '37 had the 3.78 and it was a better compromise between relaxed cruising and good acceleration. But that's just my opinion. I'm sure others will weigh in with different thoughts.

[jerry grayson]

Originally Posted by adileo

Hi - I'm curious what rear was typically put in a 39 deluxe coupe? They actually had two options?

Most 85 hp cars had 3.78 gears in the axle.