I tried a search and couldn't find anything on this. If someone knows of a thread already I would appreciate it. I recently made a deal for a 39 Deluxe Tudor. It has the original rear suspension and banjo. I will be putting a nine inch under it and I would like to keep the transverse leaf and the wishbone if possible. I realize it would probably require a panhard or two upper triangulated links. I also realize that parallel leaf kits are available and reasonably priced. The buggy spring would look much cooler under there, but it will probably never be seen. Parallel leafs are about the best all around suspension in my opinion. Does anyone have any real world experience with this? What was the handling quality like with one vs. the other? My Father's 36 has parallels and is a great car. My only buggy spring experience is in my avatar, and that is a much lighter car than the 39. Would I be wasting time keeping the buggy spring?
I have a 9" and traverse spring under my '39 coupe. I love it. The original spring rides good and there is no axle hop that can happen with parallel leaves.
Ch***is Engineering parallel, gas shocks and a sway bar. Bolts in, well designed, rides, and handles great.
With the 9" I'm ***uming that you are building a "fast" car? If so, the parallel leafs are probably your best bet and would require less in the way of fabrication, that is to say ladder bars and the like. Then again, my '39 Deluxe Tudor has all of its driveline from the clutch back just as Henry intended. It isn't what I'd call fast, but its not slow either.
I used the Ch***is Engineering parallel leaf springs on my '39 Ford convertible and was well pleased. HRP
The parallel leaf setup has been popular for a long time and some say that it is far superior. I just say that it is different, but what do I know. I have riden and driven them both ways and like 'em either way. If you get a good leaf kit with the proper rate springs and it is set up well the parallel leafs are nice ridin'. Less spoingy than a buggy spring. Usually if you get the spoing out of a buggy spring it is too soft for the car. The down side to a cross leaf is that the original spring may need to be rebuilt and some times the main leaf is too grooved to rebuild. That being the case you are normally money ahead to get a parallel kit. If you don't plan to split the wishbone you won't really need a pan hard bar. You can run one and it certainly won't hurt a thing but it is not necessary. They make the biggest difference if you decide to use long shackles to lower it. If you are leaving the suspension stock with the cross leaf it is fine without one. With the open drive in place of the torque tube you should run a torque arm. it doesn't need to be anything more than a single rod running from the top of the punkin to around the rear of the transmission. easy peezy. Anyway getting back to it you can run either. They both work and they both have their charms.
InstantT - If you go to my profile page and look at the albums there are some pictures of the build. I used 2 x 2 3/16 wall tubing to a self aligning pillow block bearing. The bearing does not need to be that big, it is what I had on hand.
I favor parallel leaf spring setup because I believe it offers inherently better body/ch***is roll resistance compared to the original cross spring. Especially so with high(er) center of gravity of a '30s/'40s sedan. Think about how the center of the body/ch***is is perched atop the center of the spring and it doesn't take too much imagination to see how little roll control the cross spring can exert compared to the more widely spaced parallel leaf spring. A few years ago, building a '47 Coupe I had at the time, I not only added Ch***is Engineering parallel leaf in the rear (with 8" Ford axle), but I also modified the front suspension with a coilover arrangement on the original beam axle, deleting the buggy spring, adding a heavier Panhard bar and much stiffer than stock anti-roll bar (Jeep Cherokee) and that old Ford cornered like it was on rails, compared to the original suspension. I am not advocating that you modify your front suspension, merely saying what I believe are the advantages of parallel leaf rear springs in your application. Ray
Quite a coincidence that I should open this thread today after a chance encounter yesterday. Hanging around for a bit at a local hot rodders gathering at the shop of a local who builds hi-po engines for all sorts of hot rods and race cars BSing with my friends. The sound of a hipo engine alerts me to the arrival of a guy who started coming by lately in his gl*** '34 tudor, nice car, BTW. He was asking around about spring re-arching, his '34 has a Ch***is Eng. setup on the rear that has lost a good bit of arch since he built the car, resulting in a too low rear stance, and bottoming in the rear if anyone sits in the rear seat. A call to C.E. got the response that "Yeah, the springs do sag a bit after use for awhile". Spring shops are getting rare and the one he found in nearby Atlanta quoted $350 to re-arch and add another leaf! This is with him doing the R&R, bringing springs to them. We explained that the springs must be dis***embled and rearched one leaf at a time, either by press or by hammer and anvil, and he sorta understood why the cost was so high. I've got 2 hot rods, an "A" Hiboy on P&J Deuce rails with 9" rear, and a transverse spring, with a set of triangulated Kurtis type bars, and the other is a '40 Ford coupe with Ch***is Eng. parallel leaf kit and 8'8 Explorer rear, shortened to use stock 'short side" axles on both sides. Kinda hard to compare them on ride and handling, as they are such different cars. The Hiboy is a pure "in your face hot rod", loud, fast, handling like a go cart, and the '40 is a cruiser with a stock appearing body, except for a slight rake and big&little tires. Both drive and ride like you would expect, and all I would change in either is that if I had done the ch***is build on the "A" myself (bought as a partially completed rolling ch***is & body), I would have used coil overs on the rear so that things wouldn't have been quite so crowded in the rear. A transverse spring takes up a lot of room under a Deuce ch***is. I respectfully disagree with those who claim little roll resistance in a transverse spring though. I've been involved in old Fords with transverse springs since the early 50s and they can be whatever you build, stiff as a board or limber as an old Buick coil spring rear.
^^^^^^^^sure the transverse spring "can be whatever you want it to be.....stiff or soft" But I think that in ganing roll resistance (stiff) you sacrifice ride comfort and vice versa. You pays your money and you takes your choice. Ray
============ That's where AntiRoll Bars shine. Greater roll resistance, without straight line ride stiffness.
Correct! [you can add an anti-roll bar to transverse leaf spring to increase roll resistance without stiffening the ride] By widening the parallel spring base you also increase roll resistance without stiffening the ride. The downside of parallel leaf springs is roll steer. If the front spring eye is higher than the avle centerline you end up with roll oversteer because the wheelbase extends as the spring compresses. Most OEM leaf springs have a low front eye and a higher rear eye [AT RIDE HEIGHT] With leaf springs need to know the spring rating [lbs/in] but also the load rating [the shape of the arch You can alter the arch [load rating] so the spring sits correct for it's given sprung weight
I don't know all of that technical stuff but I have 40 coupe with parallel leafs in back and dropped 40 axle up front with stock wishbone ,sway bars front and back. It handles well in the turns and rides OK for 40. I have a 39 set very low with parallel leafs in the back and M2 up front handles like an old sports car. Many guys on here are running the transverse spring and seem to happy with them though. I went with a 9 inch on the 40 and an 8 inch on the 39. I don't think anyone can really see the rear end under your car unless they get down on the ground to look at it.....
My avatar 39 has 8" with well known mgf kit for parallel leafs with tube shocks, so don't know how it would handle with orig banjo & transverse spring.........but this has proven to be a frustrating exercise......... Brand new tube shocks supplied with parallel leaf kit were NFG, OK on rebound side but zero on compression side, so installed air shocks...........then realized supplied new parallel leafs were way too soft with any weight in back seat, so had additonal new 2nd main leafs installed in rear spring pack.........it then became obvious a rear sway bar was definitely needed and usual kits would not install because of exhaust & elec fuel pump mountings, so a sprint car style rear sway setup with torsion bar was installed..........think I'm now close to being setup properly with decent ride and handling...........
Will try to get pics when up on hoist, but will be a few days...........getting ready for DD's in Victoria and lots of company headed this way from far away points..........
I did a lot of work on a 38 deluxe sedan for a friend a few years ago. It had the parallel leaf set up on it. Whenever we put people in the back seat the tires would rub. I ended up installing some air shocks made for a corvette . Maybe not the best fix but it worked on that car.
That would be great, and if you post it here on this thread, then those of us now on the thread should get an email to alert us you have posted it. Thanks
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