Gentleman, has anyone on here used a narrow model A rear spring in a 32 frame with 36 radius rods? I have done this on 2 in previous times with good results but my spring guy has gone & so has my data & templates! Any info or guidance is well received, Wayne
This is easy enough to figure out, the spring you will need is dependent on the space between the perch eyes on the ends of the axle tubes. Get that measurement and the vendor selling the springs should be able to tell you which one you need. If you're using, say, a Posies spring all of that information is in their catalog. I'll admit, I am not quite sure this is what you were asking for but I think I am correct.
No, it’s not easy to figure out at all, especially if you have not done this! I’m using early ford parts, no vendors here! I did contact Posies but the narrow spring is too wide for my application. Kris atPosies was super helpful but they could not offer up a spring solution! Their narrowest spring is set for 44.5” perch centres, my perch centres are 36” & I require a “standard” ride height, you now have all of the relevant dimensions & scope for this spring, I look forward to your spring detail. Suggestions as I’m thinking this is far from easy for us hot rod guys!
So your needing a model A style spring that will fit a 36” spring perch center distance. If stock is 48 I’m not sure you’re going to find anything off the shelf as that’s incredibly narrow. when I was looking for a narrowed stock spring about a year ago I couldn’t find a spring shop within three hours in Kansas City that would still turn their furnace on for work. Not sure how they function? I guess just retail now. if I were in this position my first step would be find a spring shop that can even do the work. That failing I would find a black smith that could re roll the eyes on a stock spring to match your new spring center distance. then take a cut off wheel and trim your non main leafs to suit.
I checked Posie and apparently they're no longer making the 44.5 inch reversed eye 2 inch lower Model A spring? I just built a deuce roadster with one and have used several over the years. Roadster Supply used to offer them but must be having a supply problem? I directed Ray to a spring company in Omaha but they must not be able to produce? Also check Millworks, they show a narrow A rear spring.
We have a (serious hobbyist) blacksmith group that usually will take on a challenge and seems to have a pretty deep, combined, wealth of knowledge....maybe some such group exists for you in your area that could help with modification of the spring material you already have just a thought and maybe an other dead end....good luck
St. Louis Spring made a bespoke front spring for my brother. Call and ask if they can do Model A rear style.
Just checked Millworks and they show a narrowed reversed eye Model A rear spring on their Black Friday monthly special.
@krylon32 if he’s wanting 36” perch centers he’s going to need like a 33” spring. I don’t think I’ve ever seen a model A shaped rear spring that narrow before. I’m****uming the car is both very low and channeled and he’s trying to keep the radius rods inside the spring hangers. I can’t think of another reason to have them so close together
Your right, the Millworks narrow spring is 39.5 wide using a 45 inch perch center on the rear end. I've done all my buggy spring customer 32 chassis over the years both 40 style and Model A with the 44;5 inch spring perch centers with the Posie narrow spring and it worked fine. The 36 bones do present a clearance problem in a deuce. I think a 33 inch rear spring would ride like a rock.
Yeah I’ve seen the 36 bones mounted way further out, I have to****ume they are narrow to try to fit inside frame rails.
Yes it’s about keeping the track close, the ends of the radius rods where the perch boss lives conflicts on the tyre (tire) side wall and the mounting brackets for the radius rods sit directly under the chassis flange , if using stock pieces! I have done this before but my spring guys closed up & I didn’t retrieve all of my spring data before they did!
The narrow springs work ok but my observations ere the rate of rebound was quicker which made the ride harsher, in saying that I built the frame a little heavier as it was running a 600 hp BBF. It wasn’t a lite car but the extra rear axle bias worked with the shorter spring! Interesting when you try & massage early Henry to work better!
Some pictures of your setup would really help. That being said, I am running a TCI model A frame with a rear kick and flat cross member. The car was setup with coil overs which I always regretted installing. Since the car was complete, I did not want to change the rear cross member so I modified what was there. I welded a U channel to the bottom of the existing cross member, new hangers to the rear end and used a '37 front spring which is 2" wide. I don't think you would have any trouble finding a flat spring in the length you need. I initially used a Posies spring, but it was too short eye to eye, but I bet it would fit your application. Warren
I keep thinking about your problem and it comes to mind there was a HAMB contributor that had your problem and solved the clearance problem by blending 46-48 front bones into the 36 rear bones using the dropped portion of the front bones to gain the drop down clearance for the frame. It's on here somewhere but I can't find it?
I feel that this has been a problem ever since 35/36 rear radius rods were retro fitted into 32 frames! It compounds the problem as soon as you fit a QC centre into the mix! I have used the 37/40 front springs in the rear where a 9” was used! I’m kicking myself now that I did not make the effort to get my previous spring data for this rainy day, I’ll need 3 new main leaves to pacify upcoming builds! I did lookin here for info but came up with nada!
Warren, nice set up & good call fitting a spring, this set up will not work with a QC rear which is why the A spring! Set up is a basic 32 frame with a model A rear crossmember, an industrial chassis X member, simples!
That is why I mounted mine behind the rear end, but I wasn't using a QC. I found a NOS '37 front spring but it needed more arch. I went to a heavy truck shop that actually made custom springs for various applications. They had a power anvil and re-arched my main and second leaf. They also said they could make me a new main leaf to spec. Ended up giving me the height I needed. With all the truck trains I see running around Australia, there must be a shop that cam make you a main leaf and adapt it to the other rear A leaves. I don't think you will ever find something off the shelf. Warren
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