I just fitup my 9 inch rear axle on top of the original rebuilt springs in my 49. It is a bare chassis at the moment. As a bare chassis I only have 2 1/2 inches of travel from the top of the axle tube to the bottom of the frame. I would expect over an inch less (maybe 2") with the truck assembled. Who else has been down this road? I am concerned that even with "C" ing the frame I still will not have enough suspension travel. Any ideas/experience or meaurements out there?

 

flipping the rear end above the leafs will give you about 5" of drop in the rear. 2.5" of travel is plenty. I'm assuming your running the rubber stoppers on the frame? It also depends on what shocks and the condition of your springs. We did the flip on my friends 50 F1 and we didn't have to C section the rear frame. He did have to relocate the shock mounts and welded them to the rear end housing. My concern was the rear end housing coming up and hitting the wood bed. But he hasn't had that problem either.

 

I only have 2 1/2 inches of travel WITHOUT anything above the frame and without the rubber bumper . 2 1/2 inches is my steel to steel measurement. I expect that I will lose most of that 2 1/2 inches with the truck fully assembled. Do you know what your friend has for travel with the fully assembled truck? nI did not think that my spring need to be rearched, but maybe they do. Does anyone have a good (poerhaps new) spring off the truck that the could measure the free arch?

 

Personally, I'd want about 3 to 3.5" inches of travel, but I'm no expert.

What you could do for rubber bumpers is weld a flat square section about 2 inches square off the outside side of your frame rail about an inch up from the bottom and then put some triangular gussets from it to the sides. Drill a hole in the center and mount your rubber bumper to that. I think you'd want an inch of bumper usable at minimum though....

Just a thought.........

 

I had not considered relocating the bumpers, thanks, it is a good thought.

 

49- My buddy measured his and he has 2 3/4" clearance from the top of the housing to the metal frame. He also told me he purchased red urethane stoppers that are about 1/2" thick which mount with a screw stud and nut. He bought them through Summit Racing. (check suspensions). He kept all the leafs in his leafsprings for the added stiffness, I think he said he has 7 leafs in the rear. He also used Gabriel air shocks on the rear in case he decides to tow or haul something or raise the rear a little. He usually leaves all the air out and keeps the low stance and claims the truck rides nice. Hope this helps ya.
BTW- I know he's running 12" wide wheels and he did tub out the rear section wheel wells to accommodate the wheel width. I don't believe it has anything to do with the flip or suspension? I know he left the frame original. Here's a couple pics.
https://www.ford-trucks.com/user_gal...104754.520.390
https://www.ford-trucks.com/user_gal...104755.520.390

 

imlowr2, thanks for taking the measurement. As I understand it, your buddy (nice truck-my color) has 2 3/4 inches with the fully assembled truck. That sounds about right to me. I think that my springs must be a little tired since I have 2 1/2 inches without anything mounted on the frame, just a rolling chassis. If I keep the rear on top of the axle, I will need to re-arch the springs back to original specs. I have the complete original springs-10 leaves and it is all set up with new pins and bushings. My other option is to reverse the eyes, flip hangers and remove a maximum of every other leaf. Since I will run a Jag xj IFS, I wanted to get the rear down about as much as possible and maintain the truck as a good driver capable of carrying some load. I am trying to get the rear about where it is going to be before mounting the jag since the rule for mounting the jag is to make sure that the crossmember is parallel to the ground to maintain proper geometry. I had not thought of an air shock for towing. I towed a car trailer several times in the 80's to and from Hersey with a friends station wagon with air shocks. It worked well. Any other thoughts/experience out there?

 

I'm with Ferg on this one. I think a minimum travel of 3 inches would be about right. Even then, you would have to be careful about what you hauled in the bed and be sure you have the proper bump stops. My axle is above the springs and I have 5 inches right now without a bed or fenders but I am running Chrysler rear springs which have more arch. I suspect mine will drop a couple of inches when the bed is added.

Vern

 

the 7 leaf pile-up is the answer here, if you are planning to remove a couple of leaves to soften it up I would recommend a little more clearance.

 

Well I did a load test on my bare chassis to see how much deflection would occur in the rear. I put 500# (5 bags of black beauty) on the frame right over the rear axle. Remember that I am talking a bare rolling chassis. My flipped axle clearance to frame went from 2 1/2 inches to 1 1/4 inches. Clearly I need to alter my planned approach. Does anyone have specs on the original F-1 springs or better yet have a new rear spring not yet installed that you could measure the free arc?

 

Correct my previous post to 600#-6 bags. I called a spring rebuilder to try to get specs on the original F-1 springs. Success! The original specs call for a 6 inch arch (spring unloaded sitting on the shop bench). I removed my springs and measured 5 1/2 so they are a little tired. I then remounted the 9 inch under the original 10 leaf springs. Results were 8 3/4 inches "steel to steel" with a bare chassis and 7 1/2 inches with 600 # over the rear axle. the deflection under load as you would expect was the same at 1 1/4 inches for 600 # or a spring rate of 240# per inch (both springs taking the load). Are you all still with me here? So where I come out on this is if I want to flip the axle and have 3 inches of travel I will definitely need to re-arch or buy new springs (I am a bit like Bobby and that is real money).The other option which I think that I will go to is to reverse the eyes, flip the front spring hanger and remove 3 or 4 leaves. That had been my original plan but I wanted to investigate the axle flip. As a side note, my measurements with a 9 inch indicate that the 9 inch housing hump will contact the bed floor if it was necessary to C the frame for suspension travel. The other option would be to block up the bed a bit on the frame to get clearance over the axle housing hump.

Anyone see this differently than I have seen it?

 

Sounds like your on target! You may want to consider another option with the flip kit, the fact that you can also use blocks to lower the rear end. If you have 10 leafs and plenty of clearance after the flip, you can alway adjust by adding lowering blocks between the leaf and rearend. You can't use the lowering block method on the original set up. It will raise the rear end. Something to consider?

 

My head started to hurt about halfway through that, but;

With the rear end still under the springs and every second leaf out( maybe an inch there), you could gain a bit (that is get her down a little more) with extanded shackles. Probably one to 1.5 inches. They're about $90. at Sacremento-Vintage. Reversed eye main leaves at about $65. each would get you another inch to 2 inches...or forget both and stick the rear end above the springs......

Or based on the math - any combination of the above, and the raising the front hanger/shackle......

 

you are right on the money

 

Thanks for your responses. On my last post I indicated that the axle flip for me was out unless I bought new springs (note my comment on being a little like Bobby on spending money). With my existing used springs I can't get enough suspension travel if I flip the axle. I found by the measurements listed in a previous post that with my existing springs about a 4 inch drop from my stock suspension position is about all that I can do and retain a comfortable suspension travel distance. Flipping the axle by my measurements with the 9 inch rear resulted in a 6 1/4 inch drop-too much for me.
I have given some thought to cold working my existing main leafs to reverse the arc yielding a pair of reversed eye main leaves. I am thinking of trying to do it with my hydraulic press. I believe that it can be done either with a piece of channel or railroad rail on it's side with a big hammer or working it gradually along the arc with a hydraulic press. I think that I will experiment on the press with an extra old leaf first. Has anyone done it that way?
What effective total drop has anyone else out there acheived using the reversed eye, flipped hanger, leaf removal and maybe hanger relocation on an F-1. (the F100 is a bit different). I am looking for a 4 inch drop.