Front I beam Axle Camber Question

I was wondering if any technical experts can tell me what the consequences of running a hot rod front wheel with a de-camber of about
2 degrees?

To explain if looking at the front of the car the front wheels will be on a slight angle showing that the bottom edge of the wheel is wider out than the top.

Any thoughts, not guesses would be appreciated....

Pic's attached further down.

 

Sounds like your talking about Negitive Camber. Which means that the top of the King Pin is in closer to the Centerline than the bottom. If anything this will improve the stability of the car. Negative Camber gives you less wander and a more solid feel for the road. If you want to get into suspension, Read "Advance Race Car suspension and design" by Steve Smith. A great little book. He also has the book on CD with all of the calculations to fiqure out everything for suspension, to build it from scratch.

Hope this helps!!

The Old Tinbasher

 

2 degrees seems a little much.

The recommendations that I have seen call for about 1/2 to 1 degree of negative cabmer to increase traction without causing adverse tire wear.

As in anything, there is always a "happy medium" to achieve.

 

Will it make the steering any heavier???

 

Nope. Won't make it hader to steer. It will plant more tread on the pavement in a corner, typically a good thing. Probably better with radial tires because bias plys won't roll in a hard turn like a radial

 

What is the camber of most axles set with on a new purchase?

 

My thought is that even if it does "help" somehow, it will still look like your kingpins are completely shot.

 

0 +or- 1/2 degree are the specs for new.

 

your chamber is way off with that much chamber all your doing is wearing the inside of the tire half a degree is all you need for camber

 

Fords were one degree positive (when new). that’s what I put them at when I drop them.
I think that’s about were new ones are also.

 

Thanks. Good to know. I have a magnum axle with about 1/2 negative degree built in.
I have heard that tube axles are built new, with 1 1/4 positive camber built into them?

 

I may disagree about the steering effort change. There is another angle involved and that is king pin inclination........not rearward tilt of kingpin as in caster, but angle of incline when viewed from the front. An imaginary line through the kingpin usually intersects a line through the verticle centerline line of the tire at the ground. Chrysler called this "Centerpoint Steering" I believe. Requires least effort to turn wheel with that geometry.

On a beam axle, as I believe we are discussing, increasing negative camber will also increase king pin inclination, and although the relationship between the king pin and verticle line through the tire remain constant, the increased lean of the king pin and wheel will produce the same effect as occurs with caster.
The axle will have to "rise" a bit when the wheel is turned, requiring a bit more effort. I do agree that a modest amount of neg camber can add to the stability of the steering in a straight line, and perhaps in a turn as well, but not without some effect elsewhere.

Ray

 

You are talking about caster. Caster and camber are measured on two different planes. Increasing camber will not increase caster.

 

Here are the pic's!

OK here is what I have got.
A 1950 Cadillac front spindle adapted to a ford Superbell I beam axle.
On the bench when being put together it did not look so bad.
But now I have a wheel on it the -ve camber is a little more agressive than first factored.
I have a power steering box running it.

So what do you think is it still driveable???

 

You may see a bit more after you have added all the weight.

 

You could possibly take that much (looks like way more than a couple of degrees) camber out with a simple axle bend, but you still have to concern yourself with the KPI. Ideally the centerline of the kp should intersect the vertical c/l of the tire at the tire's contact point with the road. The KPI on those spindles is fixed, by the angle of the KP bore in relation to the spindle stub.

From the looks of it the kp's c/l will be inboard of the tire's. But that's been done before with guys running reversed wheels on the front.

 

Bump!!!

 

you can run -2 camber if you want to wear the inside of the tires off.

it will corner well, but, it will ride on the inside edge and will wear inspite of the toe-in you give it.

your better off to run it at 0 degrees.

 

In the UK it used to be common to use a Ford Transit van spindle & kingpin on a Superbell axle, the angle was slightly more than an early ford spindle so you ended up with a bit of negative like on your axle, I did it once but hated the look and while it improved in the corners it wore the tyres rapidly on the inside.

 

what ever you do- DO NOT HEAT THE AXLE to bend or straighten it.

find a frame shop or old fashioned alignment shop to bend it (with the weight on it)

give it 0 to 1/2 degree positive camber

 

Thanks guys, I think I have gotten the picture now.
It will work, but not desirable, more an experiement gone wrong.
I will work my way back to Ford spindles etc.

Thanks for all your input and I hope it helps others in the future.

 

Or it'll look like a '90s European touring-car racer, if you want to run with that look. Not HAMBesque at all, but I rather liked that hunkered-down, body stretched like a bathing cap over huge rims with "painted-on" tyres, and like 4° of negative camber on the front.



I did try to sketch a hot-rod application for the look at the time, but as you can imagine it's more easily said than done.

Seriously, -2° camber might be good for front cornering force but, unless something commensurate is done for the rear, it's going to oversteer at the limit, perhaps viciously.

 

Funny, oversteer could be a good thing with a 116 inch wheelbase.
Joking.
It is dead a buried in my book, it was a trial but I under estimated the effect.
I have since got some more accurate measuring device and found it is actually about 1.6 degrees -ve but still looks way to aggressive.

The engine I am running is a heavy Cadillac flathead which may need some help to get around corners as I am told they are heavier than a early hemi.

 

Sorry to correct you, but I understand caster quite well......re-read my post.........king pin inclination is another angle, actually at a right angle to caster........check a text book on front end geometry........furthermore, I did not say increasing camber would increase caster.......but it can have a similar, if less pronounced effect for the reasons I described.


Also, read HotrodA's post...........he "get's it"

Ray

 

Sorry, Ray.

I re-read your post. You did say KPI, but it did not sound like that's what you were talking about. Reading your post, it sounded like you were talking about an inclination of the king pin towards the rear of the car.

KPI is there to add camber through a turn and help self-center the wheels, allowing vehicles to run less static camber.

It's not really correcting me, just clarifying your post. Thanks for doing that.

 

Actually KPI was introduced to get scrub radius into a realistic range as hub ***embles became bulkier and bulkier and thus, as you say, run less static camber. KPI induces positive camber in the more heavily loaded outside wheel and negative camber in the unloaded inside wheel, so it's six of one and a half-dozen of the other. Besides, at high-speed steering angles the effect on camber is too small to bother about.

 

Ford king pin inclination (according to my '35-'53 Motors Manual) is 8º
Cadillac, depending on the year, range from 4º to 6º, (6º being later spindles)
The combination of the differing built in angles of the parts is what is throwing the camber off.
If that is a cast axle, I don't think it can be bent without cracking it. If it's forged, no problem, have it cold bent.
Since you have all the brakes etc done for the Caddy spindles, maybe you can have the kingpin angle re-machined at the 8º?
Maybe not...
It would require the bearing seat faces changed and a thicker bearing and/or shims and the holes welded up and rebored or just bored bigger at the new angle and thicker bushings, lots of cu$tom machining.
I think your camber is out even more than those pictures suggest because the wheel is turned left and that makes the camber less than straight ahead.
Turn the wheel straight relative to the rear wheel and check it.

 

Yes I turned the wheels in the straight ahead position and placed a digital reading instrument on the face of the disc brake rotor which is giving me a reading of
-1.6 degrees.
The Cadillac spindles are 1950 version.

I figure if I wanted to correct it, I would have to get the existing king pin holes plugged & welded and new holes machined to Ford spec's.

It is amazing that the 1.6 degrees was hardly noticeable on the bench but when the wheel went on it sure was obvious.

 

Providing the axle is forged, and it may be more expensive, but it should be possible to have an axle shop bend the axle next to the king pin boss to change it's degrees of inclination and not have to otherwise machine anything. Just a thought..

Ray

 

OK Ray, I will ask around, it will obviously be much cheaper to do it that way also.
Ive done a lot of work on it and it would be a shame for it all to go to waste that is for sure.