1952 mercury m3
 

I have the flat head v-8 with a 4 speed in my 1952 m3 wondering what the best way is to get more speed she is a little slow for the highway. I am trying to post a picture can't get it to work

Good looking truck! There are endless ways to go faster. Most depend on the size of your wallet. What rear end do you currently have in your truck?

My wife has a 52 with a V8 and HD 3 speed. Has a Ford 9' with 3.50 gears and she can do 65 to 70 on the freeway. Don't like to do that much as I feel it's pushing the engine a little hard, 55 to 60 is just fine. We just changed the engine and trans so shouldn't be a problem now.

Welcome to the forum! Very nice looking truck.

Rimrock hit the most common modification, a more highway-friendly rear axle ratio. That won't make the truck any faster or quicker (it slows acceleration a little).

There are hundreds of options for getting more HP out of a flathead, but mostly depend on having an engine in good shape to begin with. A compression test is a good place to start, if you don't know your engine's history.

I have the same truck, and I agree screaming down the highway at 45 mph is no fun.
I am planning on doing the 68-72 F250 rear axle, and the T5 Transmission (if I can ever find one) swap. That should at least get it up to a reasonable speed without over revving the flattie.

The two common ways to speed up an F-2 or F-3 are to change the rear axle ratio, or to change the whole rear axle.

Changing the rear axle ratio can be done using a kit sold by Chuck's Trucks. Chuck also can make up the brackets necessary to bolt in an early 80s Ford pickup overdrive four speed (I recommend this over a T5 since you don't have to cut your cross member. With the T5 you have to cut your cross member). Website here: Chucks Trucks LLC., Ford Truck Parts and Restoration, Chuck's Trucks, Chucks Trucks

A rear axle swap is another common change. The axle that is swapped in is a Dana 60 from a 65-72 Ford F-250. If you are lucky you can find one with the ratio you want, typically either 4.10 or 3.73. If you are not lucky you get to swap ratios in the Dana 60. Also note that the Dana 60 has a carrier break between 4.10 and 4.56 ratios.

Really it depends on what you plan to do with your truck. If you want a nice driver and you are not going to haul anything heavy you will want to set up your truck differently than if you are planning to really use your truck as a work truck. Where are you going to drive the truck, how fast do you want to drive the truck (50, 60, 70, 80?), and how stock you want the truck to be.

I am interested in this swap (in bold), as finding a T-5 for a reasonable price is becoming a quest for the holy grail. Is this a standard or auto tranny and can you point me to a thread where this is done.
Thanks

There is a junk yard in GA that specializes in Mustangs. You might try there for a T5. They sell them right out of a wreck or rebuilt. Can't remember exact name but should be able to find them on net. Have fun.

Georgia is a bit of a jaunt for me. The shipping alone would be a killer:-hair

The early 80s four speed is a manual transmission. I am not aware of a thread that discusses it. I have talked to Chuck about that option, but I am not personally interested since I want a transmission with a "granny" gear.

Fred is right. The changing the rear axle or the ratio is the best way to give you a quieter highway ride. But at the expense of performance. So, as many of us can tell you one thing leads to another. Your Mercury should have a better flathead engine but headers, Holley 390cfm (no larger) 4brl carb, Offy intake manifold and Pertronix Ignitor (slickly replaces points and condenser) will make a big improvement. Also the electric choke on the Holley will make even cold starts excellent. Once you make it go better, particularly on the highway, then you might want it to stop better so disk brakes for the front will fix that problem.

On the other hand "Alice" is a pretty nice looking, rare truck just as she is. There are those on here that would tell you not to mess with her.

I'm not sure where you are located (it helps if you add at least your location to your profile) but if you are out west where you have longer stretches of open highway you will have a decision to make.

He's from Newfoundland/Labrador, Canada.

Your 52 M3 is an awesome truck in any form.
I Do Not see much if any difference in the price
of them today. Weather they are bone factory stock
or with some safety and drive ability upgrades. They
are both selling for about the same.
If it was me, (and you are asking for opinions) I would
do the 9 in or 8.8 rear in a higher popular gear. Than a
duel res master and a 12 volt electrical and that is about
all. This would give me the old school ride and look with
just enough modern upgrades to be safe at today's road
speeds and traffic. I would not do the power brakes unless
I planed to tow with it. Self adjusting drum brakes is all that's
needed. I can slide all 4 tires on the 62 Uni in my Avatar with
an auto transport trailer loaded behind it. With no power brakes.
I just have to push harder and know how to keep them cool on
a down grade so I have them when needed.