Im putting an early Olds rear axle and transverse spring in my Model A and need a good starting measurement (between eyelets) so I can locate the spring perches and get the proper angle on my shackles. Its a coupe with the fuel tank in the trunk and a stock Model A 9 leaf rear spring. Id also like some opinions on the two styles of perches I have pictured. The perches in the first picture look good, maybe with a gusset added to the outer side for strength. While the perches in the second picture would work out to be about $35 cheaper, they look a little spindly, but I may just be over thinking this...What are your thoughts?
the first picture is for a spring ontop, like a stock A rear.if your running an olds rear your spring will likely end up behind, pushing your crossmember back. a good rule of thumb is perches being 5 inches wider than your spring eyes. you better use the search function.
Thanks for the 5" rule of thumb, that should come in handy. If you look closely, both hangers pictured are for a spring on top of axle installation, which is how I want to do it. Im curious...what is your reasoning when you say that using an Olds rear will likely dictate going to a spring behind the axle setup? By the way, this isnt my first rodeo...I do use the search function...I just didn't find the answers I needed.
i didn't mean doing an olds rear would dictate the spring behind. just that would be a more "typical" way to do it. like a 9 inch set up.
I mount spring over and got hangers like in Vern Tardells book. I'll check to see where they came from and I believe they included dimensions for spacing. Have to see if I can find them and get back. RB
The attached pic is from Posies website. Additionally, I have a the perches you show in "picture 1". It's a Model A pickup with a 58-64 GM rear. The perches are quite close to the drums (eyes are ~46.5") even w/ the eyes at 46.5" apart for Posies posies 28-31R-C, which they market as being 2" narrower than stock. That said, I'm not familiar with your axle, but it would have to be pretty wide to even consider using the perches in "Picture 2" w/ a Model A rear spring, unless you have one custom made.
Scott...The Olds axle I have is 54" backing plate to backing plate. Using the 48.5" measurement Posies lists for a stock width spring looks like it would be do able with the "picture 2" perches, but pretty close to the backing plate. I think the other style that you used (with a gusset) will work out better for me. Thanks for your input! RB35...Thanks for checking, I hope you can find the info. I like to check out all my options before ordering parts!
I put a 51 Olds rear in our 31 Vicky back in 59-60? I cut the perches off the "A" rear with a torch, left a good portion of the part below the eye. Made some pieces very similar to your first pictured store bought mounts from 3/8" s****, with a notch to insert the originals on top, and added a gusset under it. It's got a lot of miles on it, never any problems.
Its nice to hear success stories! The original Olds rear in this car was probably done the same way you did yours...My brother bought the car in '67 and it had been a hot rod for a while. Unfortunately the last of 3 interim owners tossed the rear suspension a few years before I got the car back. It would be nice to have a stock A rear end around to scarf the hangers off of...I could also verify the eye to eye measurement...but no such luck.
I'm heading down to our annual run at Mission Bay thur-Sun so I was under the car making the usual checks, so I took a couple pix for you. I made a loop in a piece of string and put it over the left jerk fitting in the upper shackle mount and pulled it over and looped around the rt side upper jerk. Took it off and measured at 50.5"" pt. to pt. Hard to see but I had the original 31 spring in there when I made these mounts however around 78-80 my friend put coil overs on his 30 A coupe and gave me his spring which has the two main leafs bent up on each end. The bend is behind the shock but difficult to see. Lowers it about 2 1/2" but since only the shorter leafs slide it obviously rides stiffer. None the less it made it to St.Paul in 82, 85 for the nats and most runs around the SW corner of our country. The rear radius rods are home made from 1" tubing attached to 3/8" plates I welded to the rear with two heims each side and angled forward to just under the T-10 mount on the cross member with a truck tie rod end on on each. Similar to the way Henry originally did it. Never broke anything in this set up however I did bow the right side bar once with a little too much acceleration. Hope this helps you out, I suspect my 51 rear is also 54" but can't easily measure it now.
BobF...Thanks for the pictures, sometimes they are worth 1000 words. This car originally had a '50 olds rear axle with the stock olds trailing arms (you can kind of see them in the 1st photo. Since I have a set of Chevy pick up trailing arms, I will be using those. Do your tires stick out past the wheel lip? If my measurements are correct, the tread should barely stick out running a 7" cheater slick on a 7" wheel, just like my brother had it, 2nd photo.
I originally used the 51 Olds trailing arms, I bought the whole 51 Olds convert for $25 in '59, sold the top hydraulics etc for $75. I cut and welded them up so they tied into a bracket on each side of the frame under the doors. That was when I had the blown Olds and hydro in it. I attached a few pix of how it is now. I had the original steel 51 Olds 15" wheels on it after the rebuild in 78, 15" Merc on the front. Next I went to Centerlines all around but I always thought the rears stuck out too much. These wheels are from Paulsen (French Camp,CA) and I ordered them with positive back space (look stock from side) I think they're 8.5X15 fronts are 15X7. Since this is a Vicky they and 30-31 4doors have the same very narrow rear fenders. As you can see with R235 75 15's they still stick out slightly but I can live with it.
Have not found the papers yet, still looking. I measured mine at 49" at the c/l of the welded perches. Added a pic of before and after some grinding. RB
I have a narrowed 8.8 under my model A and I'm using perches in the first pic. I'm also using a speedy medium arch non-reversed spring and it sits nice. The rear is at the shop being straightened after having brackets welded on for a pete and jakes bar set up, otherwise I would measure it for you. My perches are real close to the backing plates also.
Wow, those perches are pretty stout, maybe someone else can ID them? In addition to your 49" measurement, Ive seen 48.5" and 50.5"...maybe Ill just average them all (49.33) and go for it! Are you using a stock spring? ntx...I don't have my Speedway catalog handy, but I think my stock spring is similar to their tall spring (15" tall static). Im using a raised and narrowed TCI frame with a flat rear cross member, so I have height options...I can mount my stock A cross member above or below the existing, giving me 2" of adjustability. Have you had yours mocked up? Im curious how close the perches will be to the brake line and bleeder screw?
those are the specialty ford ductile steel hangers, I used those on my model a, but it was A LOT of work t******* them down, I dont think I'd use them again, I have a set like you pictured on the right, pm me if you want them.
The best rule of thumb is the correct stock Ford Model A rear spring perch center eye to measurement eye measurement which is 49.5" for use with all stock Model A rear springs. The measurement for stock Model T rear springs is 48.5" for those using T springs. For the V8 springs, use the dimensions from the stock Ford rearends that match the spring you have, front or rear. 32-41 are mounted in tension like the Model T and As and require a spring spreader to mount/dismount. 42-48 are not in tension and Panhard bars were used front and rear to account for it.
Pasadena...Thanks for the info, it should come in handy. I never knew that the '42-'48 springs were not mounted in tension, but it does explain the use of panhard bars on those models! savoyjfas...The 5" rule of thumb was brought up earlier, but thanks!
I used the vendor from Vern tardel's book. Specialty Ford, mentioned above. One issue is, @ 49" separation on an 8" rear, the rear brakeline required some add'l grooving of the mount and even then, it's a tight bend on the line. Top backing plate bolts go from outside to inside. I'd thought about a 90d rotation for clearence, but that messes with the e-brake cable holes. Might go 180d and swap b-plates side to side for e-brake use, but everything is holding, no leaks and a hard pedal. RB
RB35...sounds like you have the 8" that's 51" backing plate to backing plate. Ive got one of those available, but am really glad I decided to stay with the Olds...the 54" width BP to BP will give me a little more room to work. Thanks to everyone for all the input and real world experiences!
I screwed up and mounted mine a little closer together that i was supposed to. Im using a t spring, but it turned out to be a good accident i guess. will help with the brake line issue, I had atlas spring narrow the main leaf a little and reverse the eyes while they were at it
Chop32 I finally found that article on installing an olds rear with the original control arms under an early ford, I posted it on your original thread. http://www.jalopyjournal.com/forum/showthread.php?p=9003193#post9003193
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