Thread: Newbie needs help w/front suspension, Mustang II or Straight Axle

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Ive been studying the spindles and was unsure about what options I have there. Seems I could have some king pins machined to accomodate something, if thats a good idea. I guess the new spindles will dictate what kind of steering is used? Also will the single spring/hairpin set up work with a heavier car?

Spindles and the ends of the axle can and have been machined to make them work together, but there are other things to consider. One thing is camber angle. The ends of the axle are built with a certain amount of angle inward to them. If you look at your axle you will see the top of the kingpin is leaned inward. Correspondingly, the kingpin is built so that it also has that angle to it, and when the two are mated the end of the spindle holds the wheel in a straight (or almost straight) up and down position, when viewed from the front. As the wheel is turned there is a particular arc to it that facilitates turning properly.

If you machine another cars spindles to fit the angle that the axle leans and the angle that the spindle leans might be different, so the wheel, when viewed from the front, might lean in or out somewhat. That is something that you might have a problem with.

I do remember seeing somewhere years ago where a guy built a Hupmobile and he had updated it with later brakes, etc. But that was probably in the 70's or thereabouts, so I really don't remember the particulars on how and what he used. Like I mentioned, some early Ford, Chevy, and Dodge vans and pickups used a parallel spring front end. If you hit a truck junkyard with a tape measure you might find one that is a close fit, that way you might get away with little or no changes aside from maybe shifting the spring to spring width or shimming the mounts to get more or less caster.

However, don't let this info I am giving you deter you from seeking other ways of doing it. I've never done a Hup so I am only giving you some possibilities, not absolutes. As for if the single spring setup would be strong enough, yeah, especially if you used one from a maybe 40-48 Ford as they were designed to support similar weighing cars. But they would entail some work there too, building a new crossmember to support the spring and mounts to affix the rear of the wishbones too. All doable but still not a drop in.

Don't get discouraged, you will find a good solution in the end, it will just take some research and trial and error. Anytime you play with a car that is not as common as a Ford or Chevy you take on some additional challenges, but having a different car in the end makes it worthwhile IMO.

You are asking good questions and that is the important thing.

Don

I'll offer up a completely different solution. Autoweld will bend up any frame you can draw up from either 2x3 or 2x4 material. They can also furnish IFS systems or you could incorporate the IFS of your choice into your drawings, then source the pieces from a boneyard or donor vehicle.

This is an alternative to fumbling with an OEM frame and adapting it to the Hup or jacking around with the stock straight axle and trying to find a safe solution that will operate well. You can have an IFS, IRS, power rack & pinion steering and 4-wheel power disc brakes in the old girl.

As Don said, you are asking questions at the start and that's a good thing.

I might start off a project like this by sitting the frame on jackstands and mocking up the tires I would use and positioning them where they look best, then measuring the wheelbase and front and rear track to begin my drawings.
Here is a chart of measurements from OEM production cars and trucks that may be of interest to you....
http://www.crankshaftcoalition.com/w...ANGE_TO_FLANGE

Here's Autoweld's site....
http://autoweldchassis.com/index2.ivnu

Opinions between straight axle and IFS will vary predictably, but for my money, it would be IFS and modern components hands-down.

Richard is right. While we all try to save money wherever possible when building a car, we have to remember that we are building a car from the parts bin, and it is going to be expensive no matter how you slice it. Sometimes those complete front end kits like he has mentioned from folks like Autoweld seem ridiculously expensive, in the final analysis they end up being very close to what a home built set up will cost, and are far superior generally in fit and performance.

We had a back half 4 bar kit custom made by Autoweld for my Kids rpu and it made building the rest of the frame so much easier and better. Money well spent.

Don