Hey all, Trying to order some new rear leaf springs for my 74'. It's a 2dr, 347 V8 aluminum heads, No AC, small bumper conversion. My plan is to lower the front a little with coil overs for a very slight front rake, and have a good street/autocross/transam style car. I obviously don't want it to ride like a truck in the rear, but i don't want it slammed to the pavement either. I have 2 problems I'm running into: 1) It's a 1974 2-door that came from the factory with the "Heavy-Duty Suspension" (4-leaf). However, It now has the small bumper conversion on it, and I never had the original bumpers but i read it was somewhere around ~70lbs for one? If so, I assume the factory spring rate would be incorrect for this config. 2) Every site is out of stock of the supposed 4" shackles and bushings that, apparently, only the 1974 model used. It appears everything else use 3.5" shackles for some reason. Will this be a problem? Note: I wish i could use my old spring parts for reference, but they're not correct for the car. I found 5-leaf springs under this thing with literally zero rate, 2" lowering blocks, and 3.5" shackles. What would you do? 4-leaf HD springs? 4-leaf HD springs with 1" drop? 3-leafs? Use the springs for a 1972 Maverick with small bumpers? I've called a few of the big spring companies, but no dice on what would be "best" to go with since they aren't Ford Maverick experts.
I think the 4" shackles were to set the bumpers just a tick higher in order to get the bumpers are the required height. The shorter shackles won't interfere with anything, don't worry about it too much. If you're going to lower the front a bit I'd go with the 1" lowering springs in the rear. That said, I like cars that are slightly lowered and not a lot of rake.
I'd order a set of 1973 rear springs (3-leaf) with at least a 1-inch drop. You don't have the weight of the big bumpers anymore, and when I put 4-leaf on mine, it rode way too harsh. Standard shackles are fine as well. The last set of rear springs I bought are 3-leaf with a 1-inch drop, however even with the 1-inch drop, with the lowered front (cut coil springs for a 1.5" drop), the rear was still way too high. Like, ridiculous. So I had to install 1-inch lowering blocks. Sits perfect now...
Counting the leafs on a spring doesn't say much about spring rate. Here's a chart on Maverick leaf springs according to the MPC Leaf Springs (1bad6t.com) Some 3-leaf springs could be the same and sometimes stiffer than the 4-leaf spring. The thickness of the leafs could be changing the spring rate is my guess.
ME, assumin' it doesn't set at a angle, I'd remove one of the center leaves of orig springs. 99.9999% new springs are going to set far higher than you want, maybe in 10K will they'll settle a little. I run 6 cyl springs in front, saggy three leaf rears are about right.
This makes sense, thanks for the info on the shackles! With this in mind, I think the 3.5" make sense. 1" Drop may be the way to go. Great info! Do you have a pic of how yours sits? I think 3-leaf with 1" drop sounds pretty reasonable. Totally right here, that chart is super useful. This helps! Good to know, haven't special ordered any leafs before so I'll keep this in mind. Threw away the old ones already..
I have never seen a difference in factory rear leaf spring shackles, and I have dismantled many, many Mavericks. I have 4-leaf rear springs on mine from Espo Springs N' Things. No alterations, all factory hardware. No drop blocks, etc I have coil springs on the front I ordered from Eaton Detroit Springs. I went with Eaton on the front because I had heard/read they were the experts on spring rate/motor swaps/ride height/etc. The front was way to high. I cut a full coil off. So with this set up I just listed, I achieved the stance and ride I desired. Ride is not "harsh" or "chuck wagon" at all.
Those rides look really good! Super helpful information too- I think I'll order my springs today. I'll try to remember to follow up here with how the car looks in a couple months! Thank ya'll so much for the info
Hey guys not to hijack the thread or anything but I have a mostly factory grabber. The rear springs are starting to sit a little low. I've kind of looked around, where can I get new ones for the factory big bumper grabber? Mustang II interchangeable?
Wow that was a great source thanks. They asked if I wanted 3 or 4 leaf, I assume with those park bench bumpers I'd want the four leaf.
3-leaf is plenty stiff. 4-leaf is for towing trailers. They use better steel than the original springs, so they are stiffer and not likely to ever sag. You'd be better off getting rid of the big bumpers anyway...
I haven't convinced myself yet to do the small bumper conversion yet. I am the second owner of the car and thinking of keeping it stock. I got it with 90k original on it. I have a driver motor in it now while I rebuild the original. when I got it, it had all it's original fluids and someone tried to defeat the thermactor emissions with a small ball bearing. From what I understand dealers would do that, well the bearing was too small and got sucked into the engine. Didn't know until I did some top end work. From my research I can't find another 74' Grabber with all of the options mine has with it's color combo. It was fully optioned (I think except for radio) and in 3E medium bright blue metallic with medium blue interior with a super soft vinyl bench seat because the owner retired in 74' with a bad back and ordered it. he died and it sat for 20 years in a garage in AZ and I bought it from the widow who let her grandson drive it and repaint it. If it's a scarce car I might leave it be.
