I’m new here... Not sure I am posting in the correct place. Please correct and advise if I’m not...I’m looking for technical advice. I just finished a 52 ford F1 ... totally rebuilt the truck in every aspect... all original with the exception of dual mater cylinder and front discs...It has a 289 flathead completely rebuilt. Original 3 speed transmission and the ID plate says 3.92 rear ratio. I can reach 45 mph ... barely... is this normal for those specs? Even though I rebuilt the front end, it is not a pleasure to drive..AT ALL . I am at the point where I will put in a 9” rear and replace the front end with aftermarket Independent and keep it as a driver.... or just sell it as is... any advice will be appreciated.. Thank you for any sdvice
my 50 merc has 3.92, stock flathead, it will go a hell of a lot faster than 45. somethings not right.
Agreed, my 49 with 4.11's a 239 and 1 to 1 transmission ratio will hit 70 mph. It will cruise at 55 mph turning 2700 rpm. (A little higher than I want so I'm looking for a t5. ) Will it physically not go any faster? What kind of rpm's are you turning? Can't speak to your suspension question since I don't really know what your expectations are but they do ride like trucks.
My advice is pull the flathead and trans for a future project and sell the truck to me . I am in the market for a truck project.
craig something dosnt add up here , ive two old fords with 3.9 diffs one sedan one pickup is your speedo telling you lies ,I look forward to your answers because mate something is wrong my sedan goes that fast in second gear
First off it's a 239. Did you rebuild the steering box correctly? Did you replace/rebuild the shackles and spring bushings? Did you check and replace king pins if out of spec? Is the steering gear tight to the frame? What condition is the drag link, pitman arm and all the tie rods? Is it greased? Do you have a shop manual so you can trouble shoot these symptoms? What type of tires are you running front and rear? I have one of these. It's wore out but it is a fun drivable truck. A F1 that is truly rebuilt should be a pleasure to drive. Something is not right. My first guess is the steering box followed by steering linkage and king pins. That stuff is fairly simple to fix and I'll be honest...... If you can't get that stuff right, how are you going to get a new front end right? It should do more than 45. Is your vacuum advance working? If you have upgraded carburetors or have the wrong carburetor, the vacuum advance will not work properly. No spark no speed. Another thing could be the clutch slipping. Are the brakes dragging? Are the wheels hot after a drive? This could be dragging brakes or something going on with the wheel bearings. You got a lot of things to look over. Don't give up on it. They really are good trucks.
Thanks for the reply... I used a mph app to make sure the speedometer is correct. Seemed to top out at 50 mph @ 2500 rpm... I’ll dig a little deeper ... if it ever stops raining here....
Any chance someone in the last 70 years did a gear change? I don't know what was available for that rear long ago,but if it got something like a set of 4:88,or 5:12 put in it that would be the end of going fast.
That was something we were talking about this morning... it’s a Dana 41, but absolutely someone over the years may have swapped one in with a different ratio... I’ll be checking that ratio in the morning for sure... thanks for the response...
Let's look at the engine..... In 1948 for the 8RT, 1949 for the 8BA ( both are really the same) Ford went to the LOM (Loadamatic) vacuum only advance. This system requires the use of a carburetor with a spark valve matched to the vacuum only advance distributor. Advance was all vacuum controlled. The only adjustment is on the little springs in the distributor. There are some period publications that go in depth with this system, namely 1959's" Fix Your Ford"...... That book addresses that system in detail. Shop manuals provide info as well. Besides a mismatched carburetor, another source of problems with LOM is a faulty vacuum diaphragm on the distributor. The above is for a stock engine. If you have dual carbs or a 4bbl , the stock distributor will not work. At 45 and less, the driving experience of a F1 should be pleasant. What could cause it to be Unpleasant? In my earlier post I mentioned a lot of stuff. Here's some more. Brakes. The addition of disk brakes complicates this some. You have more variables now. Is it fighting you when you brake the truck? Does it want to wander when you brake? It may not be braking right. There are threads upon threads on the HAMB with disk brake problems......you may want to go through them. Alignment. On a straight axle all you really have is toe in and toe out. If it's incorrect it will drive...badly. Caster and Camber.....that's getting above my pay grade but usually problems here mean a bent axle. This can be fixed but the local tire shop can't do it. A big truck shop can. They are set up for straight axles. You potentially have a mountain of stuff to go through..... Steering..... Suspension..... Brakes...... My attention would be here first as this effects drivability the most. Engine.... Drivetrain..... This effects how it goes down the road. It does not matter what the ratio is right now if the truck is not driving and braking straight. Lastly is the shock factor...... It's a big shock to go from a new F150 to a 70 year old truck. You don't ride in these, you have to drive them. All straight axle vehicles from a new Freightliner to a Model T will have a slight wander. It does take some getting used to.... Look for obvious problems...go through the checks outlined in the shop manual. It may be something really simple and you may have to warm up to it and get used to it.
I’m sorry I should have clarified... and I had a typo in the original post... it’s a 255 CI running all original equipment....including ..an original distributor .. I have some concerns now about advance... and will be checking that... I should have also stated earlier that what I meant by not fun to drive is, when you top out at 45 Mph the morons on the road have no patience or respect.. lol... they just as soon put me into the trees and get to where they are going.. all suspension parts have been rebuilt or replaced... toe and camber... it feels sharp from idle to about 2k.... but then it goes flat... and I mean flat.... there are numerous things for me to check.. as far as handling goes... at 45-50 mph it feels like your typical I beam suspension...a little drift but manageable ...thanks for your detailed responses... One thing I did notice when confirming the gear ratio..(3.92)... the wheels don’t spin in opposite directions when spinning one wheel like most rears .. either wheel will spin the drive shaft but either one can be stopped while the other one still spins... either one spins the shaft.... is this normal ?
Lose the stock distributor. Get one of Bubba’s units or a Mallory...anything but the stock distributor. Going flat sounds like timing. I have found over the years to set the timing by ear on these rather than a light.
What diameter tires are you running in the rear? That affects your final drive ratio as much as your rearend gears. Also, those steering boxes are adjustable if there's any play in it. Both that transmission and steering box are treasured hot rod pieces and certainly shouldn't hold anything back.
Along with the advance in the distributor he hit some valid points. Have you checked to see that your throttle linkage is opening the throttle all the way when you have it floored? There may be a linkage adjustment to be made or even a bolt under the gas pedal designed to limit how far you can open the throttle. Basically a throttle stop Check for anything that might keep the throttle from opening all the way. Hand choke not opening all the way because it isn't adjusted right is somewhat common. Automatic chokes not working right is real common. Restriction in the exhaust pipe? if you slide under the truck and go from end to end on the pipe is there any spot where it is smashed or flattened? On the same token have you checked the full length of the fuel line for restrictions and kinks? If you are running down the road and let off the gas for a few seconds and floor it again will it pick up and go for several seconds before it stalls out again? That would indicate a restriction in the fuel line. The letting off the pedal lets the fuel bowl fill up and you go until the bowl runs dry again. It will put put along at a lower stead speed all day long though. An FIY due to health reasons Bubba aka Jim Linder isn't doing any more distributors until his health comes back enough that he can. In case someone didn't see his thread on here.
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