Reply With QuoteThank you for reposting!
I'm reposing this as the original has long since been forgotten & deleted off the site.
(originally posted ~08-09-2006)
I Figure its about time this is discussed, as it saddens me to see so many people put so much money in to trying to make their cars handle better, be it for the street or competition, and yet constantly go back to the craptackular OEM alignment spec's... its a Travesty! So, this threads purpose it to talk about alignments and how they help or hinder your cars performance.
First off, I'm going to assume every one already knows the difference between Camber, Caster and Toe. If not, there are a multitude of resources online that can explain them.
So why is the OEM alignment Crap? Simply because its designed to do two things. A, Maximize tire life and B, Make the car understeer, and thus keep JQ public safe from their own inability to drive properly. So you can see how it may be hampering your cars enthusiasm for turning
We're interested in, as far as street cars go, in Fixing B with out Killing A. How do we go about doing that?
Well, If you look at the OEM spec's, camber wise Honda allows for up to -1.5 deg camber on the rear (part of that "make you understeer thing") where as the front is limited to -.75 or so... Why not reverse them? Run -1.5 on the nose and -.75 on the rear? Your still Technically within OEM Spec's so tire wear should not noticeably increase, and you now have more favorable spec's for turning.
As far as toe... Toe can greatly influence the cars stability and cornering, so getting it right can make or brake a cars enthusiasm for turning. However, Toe has the side effect of Eating Tires, ya you thought it was Camber that ate tires... So, running excessive amounts of toe in an effort to make the car turn better has two downsides that may not be wanted in a street car. 1. Instability under braking as well as possibly making the car tend to wander while driving in straight lines and 2. Eating tires substantially quicker then just about any amount of negative camber...
Given this, it may be best to keep "OEM" toe settings, but if you're adventurous you may want to tweak them a bit to get the car to turn better. Try this, Toe out on the front will tend to make the car turn in quicker, toe in on the nose will make the car understeer more. Given this, Running 1/32 to 1/16th toe out on the nose will improve turn in response with a nominal amount of extra tire wear. For the rear, Toe out will increase the cars tendency to oversteer, where toe in will decrease it. So, initially you may want to run 1/32nd toe IN on the back of the car. just until you get use to the cars new found handling balance. From there you can tweak the rear toe to adjust the cars balance to meet your needs. More toe in to make it understeer more (less oversteer) More towards toe out to make it rotate more.
Caster... Caster is not adjustable with the stock equipment, and very few companies make Camber + caster plates. But if you are able, Adjusting caster is a great way to improve your cars handling, with only increased steering effort as the con (not a problem on cars with power steering). Stock adjustment calls for up to 2 deg positive Caster, I'd go so far as to double that (4 deg positive caster). because after all its free negative camber as you turn the wheels (yippie!)
So, My opinion on a good High Performance Street Alignment...
Camber Front = -1.5
Camber Rear = -.75
Toe front = 1/32nd toe out
Toe Rear = 1/32nd toe in
Caster = as much positive caster as you can get...
Now, Competition alignments will be more Extream, as tire wear is less and less an issue in comparison to making the car handle as well as possible.
Opinions? Comments? Disagreements?
Thank you for reposting!
Good stuff, For my power I run just a little toe in for straight line acceleration under boost to compensate for the wander I get when the front unweights. Without this before the car would wander at high boost from the wheels going toe out slightly. With the ruts in the roads from tire studs and chains here in Seattle it would be quite the handful until my alignment guy said try it and it was a bit better. I do like to rail corners to so I had to find a happy medium, but with all new suspension and wheels I'm gonna have to start over again and my guy left the shop I go to :(
Yup, front end toe can be a bit troublesome. I advocate a little toe out to compensate for bushing compliance, given that the drive wheels will want to toe in while under power. That and Having a little toe out under corner entry is a good thing, though the car may want to wander a bit under braking.
Toe is a wonderful tuning tool, and as long as you don't go too extream you wont eat in to your tires life time significantly.
great post Zzyzx, i remember this thread back in the day. had my ep set up this way for a year or two. although i agree the ep feels great with those settings, it will be a bit tail happy, especially when coupled with firm springs/dampers. although a tail happy FWD works well on a tight autoX course, in my opinion, this is less than desirable for the street. my reasoning is that a car is simply more controllable when the front axle loses traction first when opposed to the rear. when a car begins to understeer/push, one can feel it coming via vibration in the steering wheel, allowing one to ease off the accelerator just enough to regain traction. when the rear comes loose, it is much more sudden, and gives little to no warning. the point is, the car is only as good as the weakest point. when you have less available traction on the rear, you will feel a false sense of security about what the car is capable of. when pushed to the limits, this could prove dangerous.
my suggestion would be -1.25 to -1.5 front camber. -1.5 to -1.75 rear. toe is whatever works for you, i like a hair out up front, and a hair in at the rear. caster is the more the merrier. this will give you the same front traction as your suggested settings, while increasing traction on the rear during cornering. this will most likely show an overall improvement in corner speed and stability
for those who care to read further, michelin made a great video about a very similar concept of the importance of rear axle traction, which was to educate the public about the proper way to replace 2 tires.
http://www.michelinman.com/tire-care...artire-change/
the proper way is to install them on the rear axle for above reason (even on FWD vehicles). having experienced the test conveyed in this video first hand at Laurens Proving Grounds back in '08, I learned that that you can hold considerably more speed around a corner when you have more traction in the rear. the test was a finished concrete circle track, about 200 yds in diameter. said track had about 1/4 inch standing water the whole way around. the test was to drive around said circle as fast as possible. both cars were identical, except where the new/worn tires were placed.
first car had 2 front tires with 50% tread, and 2 new rears. you could hold about 52-54 mph before feeling a shimmy in the wheel, which is a sign of your front tires losing traction. keep on it and the nose begins to push. however, you could completely regain traction simply by easing off the accelerator.
car 2 had 2 new tires up front, and 2 on the rear with 50% remaining. at just over 40 mph, unless you are a BAMF, you spin out ass backwards. no warning.
cars get 2 tires replaced all the time, and all too often it is done incorrectly. ever wonder why after the first snow of the season, so many people end up spun backwards on highway on ramps? because people think the best tires (traction) should go up front.....................
great write up! i might try this when i get my suspension and wheel setup finished
This is some great information guys. Thanks for sharing.
I have a slight drop and I've been getting my alignment to OEM specs and even though I have a camber kit install (which they also adjust) my rear tires have suffered from feathering. Will try -1.25 front and -1.5 rear since I not real low.
So I gave this some more thought. Now I'm no guru at this, the reason why I'd like your input. Negative camber will wear the inside of the tires faster, right? Wouldn't I want to have slight positive camber when the car is dropped in order to make the tires run flat on the road surface?
A car rolls when it corners. This changes the tires contact patch with the road. For this reason an optimal track setup will never offer best daily wear characteristics, and vice versa.
Positive camber would be excessive and cause severe handling and safety issues.
good info
Right. So what would you recommend for a daily that never tracks and is mainly driven on the interstate which is straight. I don't usually have problems in my front tires with wear on OEM alignment, but mainly the rear tires are the ones that get tortured on the inside.
Originally Posted by Ba82Ep3
You can get away with upwards -1.5 deg camber with little to no extra tire wear (the OEM alignment allows for a maximum of -1.5 deg camber on the rear & -.75 on the nose). Toe is the real destroyer of tires.
If you are really that concerned about tire wear, Aim for -.75 to -1 deg camber on the nose and around -.5 on the rear. Keep the toe settings within OEM spec.
Thanks for the input gentlemen, it is much appreciated.
/\this is how i feel! i just picked up a new set of coilovers and am going to take it to a tuner friendly alignment shop, so i can get this spec'd out correctly unlike at the crummy old firestone ...
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