Thread: mII spring rate.

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hi all. new guy here looking for a bit of advice. i have a 1953 ford mainline 2 door with mII front suspension, 302 4 speed auto with a/c and power brakes. car is for the most part complete (i.e. paint, interior and the like. power steering is next). i put new springs in it for a mII with v8 and air. i think the spring rate is 375. anyway, after installing, and allowing it to settle, i seem to be right back where i started from. yes i know i need a weight for the car to more accurately decide where to start from, and no i didnt get one due to the fact there really isnt a convenient place to get a weight near me, i am having to go by best guesstimate which im thinking is in the 3200 lb range.
just looking to pick somebodies brain on this subject. there are a few dirt modified racers near me, but i dont know any of them and i doubt they all would have individual wheel scales.
any help would be appreciated.

Welcome---

A couple of things---there are several truck stops or farmers grain elevators down that way for weight--

Also--is it a salvage yard front end off a M2 or an aftermarket type thing??? the spring rate will depend on where the spring is mounted on the control arm as the mechanical leverage is what effects the rate at the wheel---check Height's and the QA 1 sites/cataloques for some detailed help

from the receipts i got when i purchased the car, it listed heidts as the mII supplier. it is mounted on a fatman stub frame. of course, when calling heidts, they advise they dont make any such animal for my particular car. otherwise, ive been very happy with the car as it stops steers and tracks well. was/is very nicely put together, but i need stronger springs. at time of new springs, i also instaled gabriel heavy duty gas shocks. all was right with the world for approx. 3 months.
will check on the grain co-ops or get to a truck stop soon. kind of disappointing to put all that work into it just to get same results. not like it was a ton of work, but like most, i dont enjoy having to redo what i just did.

the car in my avator gave me fits on the spring rates--springs weren't what they were supposed to be--finally bought every spring in the chicago area ( about 30) and worked my way thru them--only took about 4 changes to get the car where it wanted to be---

also found the same issues with a late model dirt car I was involved with--several springs before the car is rite but then you can make changes and get preditabal results.

so when i built my last race car, I mounted the coil over exactly above the rear axle so the spring rate is the spring rate--not something multiplied or divided by some factor --

Eaton Detroit Spring makes 23 different rate springs for the MII system. I'll bet if you'd call 'em up, they could suggest the perfect spring from experience.
http://www.eatonsprings.com/m2coils.htm

thnk you jerry and thank you tech inspector. hopefully inspectors suggestion works better than jerry's

The dirt modified racers will have individual scales or will have access to a shop that can scale them. Ask around and you will find someone there that can scale your car in a matter of minutes. The modified guys can't race competitively anymore without scaling their cars at least once a month. Lots of guys have them around here.

X2 on Richard's suggestion.

That being said, the heaviest of MII (v8, auto, air, hatchback, T-Tops) tipped the scales at approx. 3200#, and that's with the engine weight pretty much centered over the front axle/spindle line. Not sure where the engine in yours sits relative to the axle center line, but if it's back from the original configuration of the MII then there's even less weight bias to the front springs (probably only slight). You didn't exactly describe what the "problem" is other than to say you're back where you started from (or did I miss something?) Are your springs bottoming out (which might also bring the shocks into question), just sit too low for your liking, or are you getting noticable spring bind (which would go to Jerrys comments)? If it's a fatman stub setup then you might want to check with them to get the install specs and make sure the unit was put in correctly.

the "problem" i am/was having is/was tire rub on the right side of the car as i turn left. occasionally will rub on left side while turning right, but rarely if ever. not enough actually to even mention. i replaced the springs that came with the kit that was installed on the car. i believe they were aftermasrket as they didnt have the flattened end on one end. they look like they were cut from a coil of wire that was continuosly wound. i went to a napa (auto zone, orielly's etc) and ordered up a set of MII springs, v8 w/air. all was good for about 3 months when they finally settled and seem to be back where i started at. while springs were still shiny and new, i didnt get rub of any kind. i should mention, it is rubbing the top of the wheel well. if you were to remove wheel, as in a brake job, stick head into wheel well and turn your head to where you would be looking straight up. i like em low, but i also like em driveable. a couple 2 or 3 inches raised would be sufficient, and wouldnt detract from the looks. other than this sorting of the front springs, i havent found anything about the car i dont like. well, no power steering is another project to be done this winter as well.... i hope.
a coworker knows some roundy round dirt racers, and 1 of them has the scales needed to get the car weighed. just a matter of catching them at home during this holiday season.
as far as shocks, i put in gabriel heavy duty gas shocks (new) at time of new spring install.
i wont be able to really get a best guess on where to start til i get the vehicle weight, and that may be a few days. hope this freinds buddy's shop is heated.
as far as engine location, it is pretty much centered over crossmember. i think it has a nose heavy weight bias to it, but i could be wrong. power steering could make that feeling disappear completely.
i appreciate all the good advice.

Does this front end have dropped spindles? You need to look at the upper spring pocket and see if it uses the flat upper spring end, which it probably does. Afco and Eibach both make a huge selection of spring rates for the 5 1/2" and 5" coil spring with one end ground flat. If you have dropped spindles you can replace with a standard spindle and gain about 1 1/2". Are the lower control arms level and parallel to the ground?

as i read down thru the latest posts about the tire rub, I thought about dropped spindles also

And the comments about the springs not being ground flat----usually if you don't get the end of the coli in the right place the spring will rotate til it gets there and then viola sets much lower!!!!!

lower control arms are level and parallel to the ground, and no dropped spindles. i looked at the spindles when i had front apart for spring replacement. i didnt notice if the top had a spring pocket for the flat of the spring, but i do believe the lower a frame had the pocket your talking about. will check afco and eibach as well. according to afcos website, i have what is considered type 3 spring. flatend on one end, open on the other.

This thread tweaked my memory banks a wee bit and if I recall, a post I made a year or so ago.

I took a look at the Heidt's and QA1 sites and if I'm reading them correctly, my coil over springs are much too light. While I haven't done any further research yet, a Model 'A' roadster has a weight distribution of 1400 pounds front and 1300 in the rear. One site says I should have 400 pound springs in the front, the other 350 with both saying, I believe, 250's in the back. Since my TCI chassis is set up more like a '32 with the gas tank in the rear, probably should look at 300# springs. I'm not going to do anything about purchasing replacements until I can actually check the installed angles and measure the wire diameters to see what I really have. Supposedly they are color coded, but I've never found TCI's paint dot. My records do show fronts @ 250 and rears @ 200 and a phone call to the mfr said that as well. After a "spirited" drive yesterday on a winding road, the car still wallows - badly and the shocks are turned up as far as they will go (and with F&R sway bars). Of course, the ride was during a snow flurry at 34-35 degrees.........


12/12 - The spring rates are actually 200# front and 250# rear done via calculation using a formula found in a book in my "library". Factoring in the the installed angle of 15*, they then become 186 and 232 which in my opinion is very light

i also need a sway bar. at least a front anyway. im sure that would also be a huge help.

Originally Posted by dwaynerz

i also need a sway bar. at least a front anyway. im sure that would also be a huge help.

ADDCO, Hellwig, Hotchkis as well as many race car suppliers make aftermarket sway bars, but on something other then a stock suspension, anything you do will be "home engineered" to fit. Since it sounds like you don't know the Mll manufacturer, I would probably try to find a '54-'56 version, add some adjustable links and go that way. You probably couldn't use a '53 as they were still a kingpin suspension, going to ball joints in '54, but the frame remained basically the same.

As far as weight bias, as you said way back, a 302 actually weighs a few pounds less (~40) then a flathead V8.