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I am about to have my front suspension rebuilt, fitting Harvey Bailey HD springs front & rear, and removing the rear ARbar.
I can have a little negative camber built in by shimming the lower arms, but is there any advantage for a road / occasional track-day car?
Is tyre-wear induced?
 

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From my '84 Spider... Tire set all installed at the same time... These are street tires that were never used for autocross or track events; just street use. Yes, there is an advantage to having slight negative camber (upper adjustable control arms will allow you to set the camber), but IMHO, you will realize a much greater performance improvement by taking track driving lessons than by any mod you can do to your car...

Negative Camber (edited).jpg

BTW, I don't run negative camber on the '84 Spider any more... And when it goes on the track, I use race tires...

Best regards,
 

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Negative camber gets you better front bite. Are you driving hard enough on the street to need that beyond the normal Alfa handling? I think standard specs allow up to 1/2* degree negative within stock specs. That little won't wear out your tires.
Andrew
 

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The point of negative camber is to keep the outside front wheel more vertical in a turn, rather than leaning outwards at the top, which is more the case with zero or positive camber. This gives you more bite.
Andrew
 

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If anything negative camber will help with tire wear especially if the car has been lowered. I'm running -1.5 degrees and I'm still eating the outside of the tires (0 toe). I do autoX the car every so often, but still the inside shoulder of the tires is square as it should be, the outside is very rounded. I rotate the tires every 3000 miles or so.

Will
 

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I'd guess that the tires pictured suffer from bad toe-in, rather than camber problems. This much wear could only be from bad alignment of some sort, and toe-in (or out) is the most common one on an alfa. They do not show the need for neg camber, they show the need for better maintenance. Worn ball joints or steering ball joints can also lead to this problem.

Check the alignment accurately!

Robert
 

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I ran 3 degrees - on my Ausca spider years ago until I converted for street use. Alignment other than the negative was spec correct. At low speed (<5 mph) steering was heavy, when coming out of a turn, in either direction, steering wheel kick back to center was very fast. You had to hang on to it. My Goodyear Blue Streak, Sports Car Specials, looked like the tires above. No pyrometers in those days!
On the street now I run -1/2 degree per side, with performance Bridgestones. They have not worn funny and the car is very driver friendly.
(The rear axle is also 1/2 degree negative per side on the Jack Beck / Richard Jemison 2L LS 4:56 set up.)
"How do they do that with a live rear axle?"
Fun stuff!
 

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Gordon - are you mixing caster with camber? Caster is controlled by the forward link, and controls the 'self-centering' forces on the wheel. Kinda like shopping cart front wheels. Racers use very large caster angles to get fast recovery from turns, and good tracking on very fast straights. It's often too much for street use, as you describe, resulting in very high parking forces.

BTW - there is a thread on cracks in the Burman steering case caused by these high parking forces. BTW - wide and low profile tires adds a lot to these forces. Jim Steck made a really beautiful reinforcement for these steering boxes (photo attached) that fail from this problem.

Camber is the sideways tilt of the wheel. Usually the wheel tilts outward at the top on hard cornering, rolling the outside edge of the tire under. The inside tread edge unloads and looses traction. Racers tilt the tires inward at static straight ahead so that the inside edge of the front outside tire grips in hard turns.

Controlling this is also why stiff springs are used - to cut down body roll - and very stiff front sway bars too. Drooped lower arms contributes a lot to this problem as the roll center goes below the road surface, which really stands the tire on its outer edge. Picking up the inside rear tire is just one added bad symptoms.

Increasing negative static camber (tilting inward at the top) is used commonly to prevent the outside tire from going too positive in a corner. Dropped spindles helps too, etc. Leads to bad tire wear for a street car, but itself does not usually cause high steering forces.

Robert
 

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I wasn't confused or incorrect this time! If you look at the picture, you will see the bottoms of all four wheels are tipped further out than the tops. Negative camber, I believe. I ran more in front, racing. The caster, I agree, was the kickback out of the turns.
As you discuss with Jim's box, loading forces can break the stock version of the one pictured, or even pull my ZF from the stubframe without added reinforcement.
I believe we are saying the same thing. Geometry for the track, is not very useful on the street. Unless some sort of street racing is the goal, 3 degrees negative camber will cause problems on the street.
Have you seen the tires being sold for street racing with a smaller inside tread diameter and larger outside tread diameter? I believe the article was in AUTOWEEK (AUTOBIWEEK) a month or two ago.
 

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(The rear axle is also 1/2 degree negative per side on the Jack Beck / Richard Jemison 2L LS 4:56 set up.)
"How do they do that with a live rear axle?"
Fun stuff!
Gordon, I assume your quote is the one from an old magazine road test that couldn't believe how well the Alfa handled with a live rear axle. Of course, Jack and Richard achieve negative camber in the rear by bending the axles tubes. The splines seem to be able to take 1/2 degree without unusual wear.

Robert, the most important benefit of large amounts of castor is that it increases the camber gain as you turn the wheel. The self-centering and directional stability are side benefits.

To the original question, I think Gordon's approach of 1/2 degree of negative camber is a good compromise. I ran a track day at Road America in my '74 GTV a few years ago with zero camber. You could easily see that the outside edges of the front tires were being overheated. A little negative camber would have improved adhesion and wear on the track, with little impact on street driving.
 

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By the way, if you do decide to run negative camber, use adjustable upper control arms. Adding shims to the lower a-arm mount will increase ride height as the a-arm mounts to the chassis at an angle.
 

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I've been running 1 1/2deg. neg on my street car forever with no adverse affect on the tires.
Love the way it turns in and sticks.
 

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I run 2 degrees of negitive camber and the tires do reflect more wear on the insides but not as bad as Enrique"s. Another side effect is it's harder to keep the car going in a straight line on roads that are not flat and smooth.
 

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I'd guess that the tires pictured suffer from bad toe-in, rather than camber problems. This much wear could only be from bad alignment of some sort, and toe-in (or out) is the most common one on an alfa. They do not show the need for neg camber, they show the need for better maintenance. Worn ball joints or steering ball joints can also lead to this problem.

Check the alignment accurately!

Robert
No, there is nothing wrong with the maintenance or components, and the picture was not taken to illustrate a problem... The specs that I used (and will use depending on the occasion) come from a well known old-timer, in his day, Alfa racer of the year and they are for the whole front end, not just camber... With the set-up both front tires will wear the same way, and the car performs very well - no issues tracking straight either. (Those are stock Campagnolo Daytona rims, 14 x 6, with 195/65-14 tires.)

For several years I drove my Spiders regularly (all three that are in my signature) between MD and OH taking US 50 all the way. Yes, 508 miles mostly on back roads, and with some memorable stretches filled with great switch backs and incredible scenery. One in particular has 90 continuous miles of no passing. This is definitely a route for people who enjoy hours of spirited driving and remote settings.

When I was working in Cincinnati my manager (big Corvette guy), knowing about my driving passion, asked me for the route, as he was bringing his Toyota MR2 out from Baltimore to Cincy over a weekend. When I got to the office on Monday morning he told that he was cursing my name all weekend. He described the route as treacherous, and told me that he headed for the Interstate at the first chance he got, but he said he still "smoked his brakes going through the mountains". Good thing we got along great, and even though we both moved on we've stayed in touch, but he never let's me forget his "smoked brakes"!

Anyway, one of my points is that the wear on the tires is significant. IMO, it reduces the life of a street tire by half. Of course, all of this is relative. If someone does not drive his car all that much, the tires will have to be replaced due to age before wear becomes an issue. I noticed Murray's comment about his tires wearing in similar fashion, but not as much. Well, I'm sure that if Murray drove his Spider as much as I drive mine, his tires would wear the same. And mind you, the Alfas in my signature are real transportation for me, and I reach for the '84 Spider keys more than any of the other cars.

My other point is that I, personally, do not believe it is worth to set negative camber on a car that is mostly driven on the street. (At least not a track type set-up.) On the streets, and even on the roads with switch backs, we just don't encounter anything close to the extreme conditions we see when driving on the track. Not once have I ever been doing the drive that I described with a stock set-up and wished that I had had negative camber. Of course, when it comes to handling feel and personal preference, everybody's mileage varies considerably, but what I have seen and experienced consistently is that the bettering your driving does more for performance than any modification.

Last, a few years back, when I took the picture I posted, it was not a random event. I am very meticulous about keeping track of what I've done and recording (for my own benefit) any observations. The picture was taken at the shop when a new set of tires were being fitted, as part of routine maintenance. The shop waited for me to able to take the picture before dismounting the tires precisely because there wouldn't be an opportunity to do this again. After years of using the set-up, we had discussed going back to the stock set-up so that the car would be concours correct. And that's what we did. BTW, those tires had about 18k miles when the picture was taken, and the Spider is the one in my avatar that is running on the track with it's legal roll bar and stock front-end set-up.

Best regards,
 

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Be wary of results from a race track as opposed to how you are going to use your car.....
 

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½-1½ degree negative camber should not be a problem for inside tire wear, and will as many say, give a bit more bite in corners.

One side effect from negative camber ,which i don't think has been mentioned in this thread, is the reduced stability and brake efficiency under heavy braking.
 

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Peter is correct. This condition can occur especially with wider tires. Excessive negative camber can result in reducing the tire footprint and reduce straight line and braking stability. An alternate way to achieve negative camber in corners, which is the only place you really need it, is to add caster. This results in the outside tire gaining negative camber only when turning. And, I acknowledge the inside tire does achieve positive camber, but the gain in negative camber on the outside tire offsets this.

Another issue is the effect on overall car cornering balance. Adding negative camber to an otherwise well-balanced car will certainly improve front grip, but may well have the effect of creating or increasing oversteer since nothing was done to the rear. A good example of this was when, many years ago, I greatly increased front caster on my 1750 Autocross Spider. The front grip increased - with such resulting oversteer - that I disconnected the rear sway bar.

Adding negative camber (or caster) is appropriate if you intend to change the cornering balance of a car. If you just do this because it seems like "the thing to do", you may suffer unintended consequences.

...One side effect from negative camber ,which I don't think has been mentioned in this thread, is the reduced stability and brake efficiency under heavy braking.
 

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Hi all,
Just an addendum to the original poster, about using harvey bailey spring kits:
I've had this same kit since about '99. Early on I ran the front springs with no extra spacers, just the usual rubber pads on each side, and the front wheels with zero camber. No spacers/shims meant that the lower a-arms pointed up going outboard. The combination of that plus zero camber meant that (at least in my experience) there was too much lean over onto the tyre edges. On a few occasions in warmer weather, the front end went completely "greasy" from what seemed to be the outer tyre edges over heating. This is using street tyres but on mountain twistys.
I've since raised the front end with 11 or 12 mm shims, which on my car puts the lower a-arms flat, and have -1/2 deg negative camber as many others have written here. Caster increased to the limit possible before the upper "I-arm" gets too close to the chassis. The setup works much better now, at least as I can tell. Front end grip much better and seems balanced with the rear, on track days.
Cheers, for what it's worth...
Neil
PS: for the rear end, I originally added an inch spacer as things seemed way too low to me. At the same time as I did the above changes, I removed the spacers and shortened the straps. No rear ARB at any point, which I think was also the HBE recommendation. Car looks a tad high in the front but goes very well, again as far as this modest driver can tell.
 

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While there's been a lot of good posts on how it's good, and how it works well....

The real answer of why is that it's a compromise due to the fact that the suspension does not hold the tires in the correct orientation vs. the ground when the car is tilting to one side or another.

The goal is to maximize the tire contact with the road for best grip at all times- as has been pointed out. But while many post about cornering, taken to the extreme- camber can have a big effect on braking, too.

Anyway, it's all a compromise between tire angle, springs/roll bars, and suspension geometry to keep the tires aligned properly with the road.

(note- this isn't to say vertical is best at all times- optimum angle is not the same for braking and turning, or maybe even lowest rolling resistance.... So there's a lot of compromise going on....)
 
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