Another gear ratios question
 

as you all know I have a super deluxe new engine goes perfectly and quiet.
My son bought a 1950 custom 4 dr. another silent V8. My 46 rides like a
town car No rattles at all. The last time I drove a 1949 the car was young and
so was too. Now I drove the kids car and its like a 2020 something car? This
is a silent rocket. My 46 is too a rocket BUT its comfortable normal at 55 mph
which is fine but the kids 1950 does that in second? what in the world gears
does that 1950 have? It doesn't lug taking off in first but its gone off the
line in second then to third its like idling at 50 with no noise & no OD. I am
not into math or axles but correct me; my 46 may have 3:78s so whats
his 1950 got 2:92 or 3:1's ? I know its cabin fever but for conversation,
we both have the 100hp engine and off the line before I go in 2Nd he is gone.
Like me second him still in first? both cars are original not messed with.
Oh well I'll stick to machining that I know. sam

Re: Another gear ratios question
 

Have you looked for a tag on the rear end differential? I'm not a mechanic at all, but I've just started learning about differentials for my 52 F1 -It has a Dana 44 with a 3.92 gear ratio. There should be a tag bolted to it with two numbers and a line between them (Mine is 47/12)

Divide the first by the 2nd and you'll get the gear ratio. At least assuming no one has replaced the gears inside. I confirmed mine by going for a ride and comparing the tach to my speed and using an online calc. and it's a 3.92

Here's the link
https://spicerparts.com/calculators/...rpm-calculator

BTW - i have a 239 flathead. Cruises comfortable at about 60 to 62 - seems to be the sweet spot for it.

Re: Another gear ratios question
 

“BTW - i have a 239 flathead. Cruises comfortable at about 60 to 62 - seems to be the sweet spot for it.”

Total agreement, I have same setup on my 52 F1.

Re: Another gear ratios question
 

I have 3.55's in my '51 (no overdrive). I had no problem cruising at 60-65 with the somewhat tired original engine. With the new 255 Merc, a 70 mph cruise is easy, except in heavy traffic. This is not a problem with the car, but with other drivers.

I am in the (lengthy) process of installing an overdrive, but find that the 3.55's are optimum (unless you live in the mountains).

Re: Another gear ratios question
 

It is possible the axle in the 50 was swapped years ago for one from an automatic transmission car. The auto cars had either 3.31 or 3.54 ratios. Sounds like your son's car has the 3.31s.
Also, engine speed can be very deceptive. A really well balanced engine will feel like it is running much slower than other engines at the same speed.

Re: Another gear ratios question
 

I’ve got two ‘50’s and a ‘51..... all 3.73 rears. My 50 cruises real well on the roads I drive. I use it a lot in good weather...... Mark

Re: Another gear ratios question
 

3:31's thats a thought last time it was up on the lift I didn't even think
to look for a tag because we haven't driven it yet but when we did it was
a wow factor......

Re: Another gear ratios question
 

One more questions, have you driven the cars together? It is not impossible the speedometer in the 50 is reading much higher than actual road speed.

Re: Another gear ratios question
 

No I didn't go by speedometer more like the feel and sound and the trees
going by LOL

Re: Another gear ratios question
 

I downloaded a speedometer app onto an old android phone and use that to check my speed, I tested the app against several newer car speedometers plus a dedicated GPS and it it accurate.

Re: Another gear ratios question
 

Quote by big job:


"I know its cabin fever but for conversation,
we both have the 100hp engine and off the line before I go in 2Nd he is gone.
Like me second him still in first? both cars are original not messed with."


Really sounds like more than just a gear ratio thing. I wonder if a good checking of all tuning and adjustments (does the throttle open all the way?) of both cars might shed more light. Of course, I may be full of you-know-what! :)


Terry