'51 Flathead 6 Towing Capacity

[Wood and Steel]

Hi all!

 

I've been thinking about getting a small sailboat and thought it might look nice behind my '51 Cranbrook. What would I reasonably be able to pull at highway speeds? It's currently stock, but I intend to switch to disc breaks and a t10 when I find one for a decent price.

Edited October 20, 2021 by Wood and Steel
Words

[Sniper]

I am currently out of town so my info isn't with me.  But the owners manuals should tell us, if anyone else has one?

[DJ194950]

Lots of questions with no answers, but where do you live?

Terrain to be where transporting this boat?  Distances?  Road conditions?  Overall motor/vehicle condition?  Approx. weight of towed vessel?

 

Last will insurance cover you while towing?

 

I love the idea if this will work out OK!

 

DJ

[Bryan G]

Not much help, but the original owner of my 6 cylinder 51 Ford was a farmer. It had a simple hitch attached to the rear bumper (I still have it, took it off to avoid shin damage.) I imagine it was used to haul a farm wagon or move implements around. My gut tells me your car will be fine towing that boat.

[James_Douglas]

https://www.allpar.com/d3/cars/desoto/suburban-1951.html

 

The answer.

[sidevalvepete]

2 hours ago, James_Douglas said:

https://www.allpar.com/d3/cars/desoto/suburban-1951.html

 

The answer.

What a fantastic narrative. Thanks for posting. Certainly a few things to learn from here.?

[pflaming]

Well, not recommended, but getting the job done! 

[Plymouthy Adams]

you addressed the one concern I have for these old car and towing anything....the attention to the brakes.  Most these are not adjusted with the proper tool and are not as satisfactory as many think.  The plan to swap to disc would be a major safety upgrade for stopping power, suggest this be done prior to testing other towing capabilities.   Second concern is the style hitch you install and suggest a receiver hitch with forward frame ties.

[pflaming]

I fully agree with the above post. I would add that a hitch leveling device also a must for me. I don’t recall the correct term. 

[keithb7]

My friend went all-out with this New Yorker. Straight 8. Have a look at his load. He took his family from BC Canada, on a long tour. Camping. I think they made in into New Mexico and had to turn around when the pandemic broke out. 2019. Pretty brave in a 1948 car in my opinion, but hey to each their own. He did say speeds were pretty bad on hill climbs. Mountain passes. If I recall down into the 20-25 mph range. Hugging the shoulder.

 

You can read all about his story here: 

https://forums.aaca.org/topic/285532-1948-new-yorker-2-year-road-trip/

 

 

Edited October 21, 2021 by keithb7

[keithb7]

[James_Douglas]

I cannot address Plymouth and Dodge, but I can Desoto and Chrysler.

 

The one item that I would change, and did on my '49 Desoto and will on the '47 Desoto is the rear cross member.

 

These things are flimsy and worthless. There only job is to keep the side frame rails at a specific width and to hold a couple of body bolts. What I did was build a thick wall tube to replace it that had holes drilled in it and the holes had thick wall round tubes welded in. This created a place to bolt in a custom designed hitch.

 

I would think about it.  James

[greg g]

Based on recollections of early life, my father had a utility trailer that he built using a pickup truck rear frame section, bed and front axle and springs.  If memory serves it was an IH kb 1 that was the base, these were half ton rated.  In NY at the time your trailer had to be labeled with its empty weight, payload rate, ( you paid your registration  fee based on this weight, and the total weight of the trailer and load.  I believe the numbers were

Unld weight 620

Pay load weight 1200

Gross weight 1820

 

He used this as a dump trailer, parked next to the garage till it got full enough for a trip to the town dump. He used it to haul home improvement supplies, including bricks, cement blocks, mortar, sand and gravel, framing lumber. Siding, shingles,  I did see it with 8 half kegs of beer, and 20 bags of ice hauled for a family reunion.  I believe these are 130 pounds.  I know it was over weight on a lot of occasions. We also used it to haul camping gear etc on fishing trips.

 

He pulled this with his 54 Meadowbrook 230 with fluid drive and three speed.  He never worried about getting or staying going, but he was always concerned with stopping as under 2000 gross weight, trailer brakes weren't required. The hitch was a bumper style.  I do recall He installed helper springs on the car when the 2 bedroom addition he and a friend put up, most of the supplies arrived via that trailer.

 

He built it in 1955 or so, last time I saw it it was full of fire wood.  By then axle had been reinforced. 8 ply truck tires were on it, the tongue which had been schedule 20 pipe had been swapped for 3 inch channel and triangular braces. He added barge boards for more capacity but still no brakes, but it was behind his Ford pickup during this use period.  Don't know when or where it disappeared. Probably he was still only worried about stopping. 

[Los_Control]

Just now, keithb7 said:

He did say speeds were pretty bad on hill climbs. Mountain passes. If I recall down into the 20-25 mph range. Hugging the shoulder.

New Mexico is tough on  cars with a carburetor. Albuquerque is over 5k feet altitude. So you tune your car to run with that spec.   First time I drove to Santa Fe  I fouled 4 spark plugs and had to limp home. It is over 7k feet. Just driving to the edge of town in the Sandia foot hills the altitude changes 500' and affect the way it ran.

Go south of town and you drop down to 3k feet altitude.

This was with my 1987 Ford work Van with a 351/C6 trans .... 500cfm Holley 4brl. It ran great around town, but the constant changes in altitude messing with the air/fuel ratio was murder.

 

I just suspect your friend was fighting the same issues, not really under powered but fighting altitude issues. Northern New Mexico into Colorado is beautiful country.

[pflaming]

I believe an electronic distributor solves that timing problem. Am I right about that? 

[Los_Control]

Just now, pflaming said:

I believe an electronic distributor solves that timing problem. Am I right about that? 

Paul I do not think it is the distributor. The 1987 Ford had a carburetor but it did not have points. It was electronic.

I think the principle is proven when drag cars go to the track and the weather or humidity really has a factor in how well the car will run that day.

 

We fine tune the air/fuel mixture but when we live in a area where the altitude changes the lean/rich on your carburetor also changes.

Denver Colorado is touted as the mile high city. Fact is Albuquerque is higher altitude ... by a few hundred feet, Santa Fe is higher by a few thousand feet, Denver is recognized as mile high city because it is exactly 1 mile high. It is not the highest.

So Cruising around New Mexico in a old car you will find carburetor issues.

 

@pflaming how is your move going? Hope it is smooth.

[keithb7]

Think about the weight of air. Think about miles of air above us, the weight of it pushing downward. Creating atmospheric pressure. At sea level 14.7 psi natural atmospheric pressure. Sort of like having a turbo, boosting the air pressure down into our carbs and into the cylinders. A free boost assisting the pistons, sucking down this air. A little 14.7 psi boost. Then we tune our carbs so they run just right. The right amount of fuel is jetted and dial'd-in to create the best combustion and horsepower in our engines where we live and drive.

 

Now travel up a mountain 5000 ft. The layer of heavier air above you is now 5000 feet thinner. Now you have about 12 psi. You have less free air boost. Each time the piston draws in a gulp of air, it gets less in the cylinder. Now you need less fuel to match up with the lower amount air coming into the cylinders. Your carb was tuned for sea level. Now you're running rich, cylinder air intake is down. Compression is down probably down too. Suddenly your horsepower is down. 

 

Fuel injected vehicles can compensate pretty well. Carbs cannot. 4 strokes are less sensitive to elevation changes than 2 stroke engines. 2-strokes really run like crap when you run them at these various altitudes with the same jetting (air/fuel ratio). You lean out 2 strokes to go higher in elevation. If you come back down to sea level and forget to re-jet, the two-stroke seizes the engine. Too much air, not enough gas/fuel mixture. Runs hot! Bet performance ever! Briefly, then the engine seizes!

 

One time I was in the mountains of Peru. 13,000 feet up. My head spun at every movement. My body ached in spots. Tingling. My heart pounding & chest burning after climbing a simple set of Inca steps. 8.29 psi approximately. Less oxygen in every gulp that I took. The vehicles still drove. The lamas still grazed. Yet I was feeling it. Big time. 

 

Wait! Now I know why the special crown & pinion gear sets are listed for specific flathead era Mopar cars sent to Bolivia. 4.89 or something crazy like that. They needed it to work at those elevations and climb hills! Power was probably lacking.

Edited October 22, 2021 by keithb7

[Sniper]

I've driven thru Albuquerque many times with a carbed car back in my sailor days.  Can't say I recall any issues.  Now if I lived there the tune might matter more, but just passing thru wasn't an issue.

[DJ194950]

19 hours ago, keithb7 said:

One time I was in the mountains of Peru. 13,000 feet up. My head spun at every movement. My body ached in spots. Tingling. My heart pounding & chest burning after climbing a simple set of Inca steps. 8.29 psi approximately. Less oxygen in every gulp that I took. The vehicles still drove. The lamas still grazed. Yet I was feeling it. Big time. 

Your supposed to buy a bag of coco leaves from the locals to chew on before and while at those altitudes or so tells me my nephew who has relatives (wives side) that live in Peru!  Solves the issue mostly.  He tells me!

 

DJ

[keithb7]

You know what comes from Coco leave....No pain from any illness would be felt! Lol.

[Sniper]

Well, I dug out my owners manual, not a word about towing.

[chrysler1941]

Don't know what your highway speeds are, but my 41 towed this converted vintage all metal horse trailer 470 Miles several times for the Old Style Weekend rally in Sweden doing 62 Mph with no issues other than frequently stops at gas stations. 

[Bryan]

Only thing I learned about towing is when I changed the ring and pinion set on my 1992 Dodge Dakota.  In the manufacturer's info it had tow ratings..said 3.2 ratio "not recommended". Then it listed higher ratios..towing capacity increased for higher ratios  3.9 etc.  Also seen other info where rear tire load ratings were important, plus ratings on the hitch. Bumper alone had a rating, then higher would be a rated hitch attached to the frame.  That's all I know..

[greg g]

U haul has been renting trailers since just after WWII. Give them a call or visit.  If they don't go back far enough perhaps the have something similar like a 63 belvedere with slant six and manual trans.  A friend had a 63 Dodge crew cab pickup that he towed his modified 4 cylinder dirt track race car around with.  That with tires, tools, and fuel in the bed.  It had a receiver style hitch welded to the step bumper.  The tongue weight was such the both of us could lift it if necessary.  It was a slant 6 automatic.  Wouldn't get over 60 but always got him to and home from the track.

 

If your car has collector or historic tags, you should check what motor vehicle laws and you insurance  carrier for what coverage limits apply to your situation.  I have been told but never enquired further that it's illegal to tow a trailer with a Historic registration in NY.  

 

Since it's illegal insurance won't cover the towed vehicle or any damage attributed to it or its contents.  So if the trailer flips spilling full beer kegs which damage other vehicles or crash through someone's front door, you are on your own as far as paying damages, fines, and costs involved.

 

It may be more complicated than will my car or truck pull it?

 

[laynrubber]

I have towed this for a couple trips, 1974 Boler camper. Estimated with gear inside to be around the 1600ish pound mark. Now the only places we have dragged this is around Saskatchewan which is “mostly” flat but there is some elevation changes in the north where I am. I could keep it in 3rd overdrive and stayed at the posted limit which here is 110 km/hr on double lane any faster and it felt like I was pushing it too hard. I have upgraded the brakes to dual system disc front.