I've purchased a set of Model A split wishbones to run on my 34 coupe. Engine is going to be a 348W chevy. I've done a little research about the strength of them and have been getting mixed reviews and advice. Some say they're strong enough to run with a v8 and some say no way. Any help? Ironically it's our hunt to be individuals that make us all the same.
My 1939 has a traditional wishbone frontend. I run a 350 ci. Chevy. The wishbone setup works for my heavy sedan. You can go to Pete & Jake's website. I think they have a section on the wishbone setup. Or give them a call Tuesday and talk to them. They have been selling that setup 40 years.
I know some people get confused about this so I am going to be blunt: are you talking about the front wishbone? Because the rears are called radius rods.
He is probably talking about front bones since he said "split". Of all the Ford wishbones, Model A's are the weakest, but some people still use them. I wouldn't personally, I would go to something like 37 bones and cut the front spring perches off and round off the cut edges. The 348 is heavier than the 4 banger these were designed for, so better to err on the side of safety. Don
What does the wishbone have to do with the weight of the engine?? They're not helping hold it up, they locate the axle. I use a set of split A bones, I've got a 283 in my AV8 Pickup, not as heavy as a 348 but still, the wishbone isn't holding it up anyway. As far as them being strong enough, I live in the Detroit area, have you heard about the roads around here?? Once I leave my driveway it's like being on a bombed out runway! I drive this thing a lot and I've hit some holes around here that would make a lot of people think twice about even driving their hot rod here. I think the "model A wishbones are weak" is a little bit of an over reaction. Maybe there are stronger bones but these certainly aren't going to fold up like paper either. I would trust these over any currently made metal bone or hairpin that's for sure.
Just wondering if they would be strong enough if the spring was mounted on the split wish bones(Spencer,Rollin Bones style)? Pete
That's what I'm sayin, I didn't get the whole weight of the engine comment. The bones have nothing to do with it.
The rolling bones style suspension puts a lot of load on the wishbones and 348s weigh a ton.....use the strongest bones you can get and don't let the shackles pull laterally too much ( too horizontal ) the closer to vertical the less " pinch" toward the center....keep us posted and good luck! Posted using the Full Custom H.A.M.B. App!
That is a different story if you are going cantilever the front axle it would work but there are forces in two directions. 1 the weight of the car downward 2 the spring pulling inward which is the weak direction. Later bones 35-48 are considerably stronger and longer and I think that longer looks better and more balanced. If I were going to use A bones I would stiffen them by splitting them in half the long way and removing the yoke. I would then weld a piece of 1/4" flat bar to the yoke at the proper angle for your 5-9 degrees of caster. I would taper it to fit the bones drill a hole through it and weld the appropriate size tube in it leaving it a bit long. I would also weld a piece of tube to the end and tap it for the thread of whatever you are going to use for the attachment to the frame. After all that I would drill the bone halves where the spring attaching bung is and then weld the two halves to the 1/4" flat bar and around the bung. This will strengthen them considerably. One other thing to think about is where your tie rod needs to be. If you use it as is the spring will need to be about 8" behind the axle unless you can squeeze the spring between the tie rod and axle and still be able to turn it lock to lock. DO NOT!!! put the tie rod out front as some are in the habit of doing because it will not have proper ackerman and your tires will be fighting each other in a turn and it is UNSAFE! If you insist that the tie rod be out front then the ends of the of the steering arms need to be bent outward so that if you were to put a string line from the center of the rear end it should pass through the center of the king pin and the center of the tie rod end. Usually there is not enough room to bend the ends outward as they run into the backing plates before you get enough. I hope this helps. Jim Ford
I have run A bones on my roadster for 24 years. No problem. They do need to be pie cut to get some caster. I made complete new ends to get the right axle fit and to drop them down for tie rod clearance.
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