wrightcomputing

iTrader: (5)

I am interested in increasing the camber on my rx8 and want to do it myself on the driveway. Mainly to gain experience and so I can calibrate it for Autocross. I Autocross once a month and am currently wearing the outside 2" of the front tires I recently switched the bald edges to the inside. We checked my alignment and my toe is around 0 which is where I would like to keep it and my camber is about 0.3 degrees. It is my understanding that you can get about 1.8 degree from the stock suspension, which is what I would like to achieve.

Does anyone know where I can get a guide for adjusting the camber, or can offer me a few words of advice? I know adding camber will affect the toe but I know how to straighten that back up again.

I was advised to get it done professionally but my thought is if I try to do it myself and mess it up then I just go and get it done professionally and I have lost nothing. If I do a good job then I will feel great and have added another string to my bow.

Thanks in advance for any advice you may have to offer.
I have searched for this and can only find info about what the settings should be not how to change them.

fastlaneracing

And how are you going to verify your toe and camber in the driveway? very little adjustment on toe will give you alot of toe in/out.

It can be done of course but let an shop do it instead.

bse50

The problem with doing it yourself in the driveway is the accuracy. Just it.
The workshop manual should indicate where the adjustment bolts are, if not just jack the car up and you'll see them.

Highway8

iTrader: (11)

If you have a camber caster guage, a flat driveway a tape measure and some simple toe plates, there is nothing wrong or inaccurate with doing your own alignment. An alignment shop has expensive equipment to make it a fast and easy process for the tech who works on hundreds of different cars.

Camber effects caster and caster effects camber. If you use both adjustments, you should be able to get close to 2.5deg negitive camber in the front and 1.5 neg in the rear. Those are good number to shoot for.

wrightcomputing

iTrader: (5)

Thanks for the advice. I am going to use a metal plate on each wheel and measure the distance between front to back to check the toe is correct. A may also check by attaching string across the wheel hub and pulling forward and measure the distance to get more accurate results. Not sure about measuring the camber. I think I will go to autozone or similar and see if I can rent the camber caster gauge for the weekend.

Highway8

iTrader: (11)

I am not sure what autozone will rent you, but check out the aligemnt tools you an buy.

http://www.soloperformance.com/Wheel...ent_c_104.html

wrightcomputing

iTrader: (5)

I have just found a great video on youtube that tells you how to check your alignment. It is a 3 part video this is just the first one, It shows you ho to check alignment only using string, water,, plastic tubing, tiles, a good spirit level and some maths.
http://www.youtube.com/watch?v=sZoL1gaWedA&feature=fvw

bse50

That's not how you want to do it for autoX and Track duties. It may be ok for the grocery getter though.

Highway8

iTrader: (11)

WHY?

If you can get repeatable results, there is nothing wrong with it. The important part of aligning a track car is to document your alignment, handeling resultes/notes, tire pressures cold, hot and tire temp readings. There is no magic alignment specs, so as long as you can take repeatable readings it will allow you to make adjustments. Who cares if your actual camber is neg 2.1 but you got neg 2.3. if the tire temps tell you that is the correct setting, then it is correct.

The level surface is important but even if its not perfect, you can still measure and make changes. The important part is repeatable results and gathering data at the track.

wrightcomputing

iTrader: (5)

I think this method is pretty good for measuring, that the way it was done before we got all the fancy equipment. When you modify a car you should do as much work on it as you can so you know whats going on. I bet everyone can tell you about a time they took it too a garage and some idiot messed something up. When I bought my car it had odd sized tires on the back 225/45/18 and 245/45/18. At least if I mess it up I know I am the idiot and what I did wrong. I also fix things for a living and love taking things apart. I will have a go this weekend if I get chance and let you know how I did.

bse50

You need solid references to make solid adjustments. If every time you adjust your camber you're 1mm off with some wire, the car is not on a plane surface etc then your results will be different from the previous time.
It's ok to adjust the camber while at the track (for racing purposes, of course) but even there you have a solid starting point done with the right tools.

TeamRX8

iTrader: (25)

setting camber is easy, getting the toe square is teh trick to it all

wrightcomputing

iTrader: (5)

Back to the original question how do you actually adjust the stock camber is it a camber bolt that you rotate or do you need to add shims or washers?

Boyd

There is a camber bolt on the lower control arm that you rotate, you don't need any shims or washers. You should be able to get -1.5 on each side. Hopefully, your bolts aren't sized as mine where. It is a PITA to cut them loose and replace.

wrightcomputing

iTrader: (5)

Thank Boyd. I am looking forward to playing with this over the weekend hopefully it will all go well.

04Green

iTrader: (1)

Option 2, maybe.

I have one of those 5 year alignment policies they sell at various tire stores.

I take it to them, write down what I want, they do it. Running -2 in the front, -2 in the back.

There are several track threads that talk this.

EricMeyer

First off I applaud you for wanting to tackle aligning your car yourself. My experience is those that want to learn how to do this end up on a wonderful journey of learning how to maximize their cars traction potential. You'll find huge gains (even if you do it wrong) in both a better contact patch but more importantly, reduced cost of expensive tires. May I suggest you also investigate information about aligning Spec Miata race cars. Racers of spec miata's speak a lot about aligning their cars --- much more than the RX-8 community. The suspension is very, very similar.

SMART STRINGS are a tool that most serious Club Racers and professional teams use: http://www.smartracingproducts.com/c.../alignment.htm

Products like this are also very common: http://www.longacreracing.com/catalo...d=1299&catid=5

We run a system like this and check our cars several times over a race weekend: http://www.mktechnologies.com/products/mkt3800.htm

Here is a wonderful little gem. I love this thing: http://www.mktechnologies.com/produc...mber_board.htm

I've just offered some pretty high end items for the DIY. Journey out to Sebring during the 12 hour race weekend and walk around, around and around and wait for the cars to come off track. Follow those cars of the faster teams and most likely you'll see them put the cars on the scales after coming right off the track. WATCH how they do it. Count the number of people involved and understand what thier role is. Strike up some conversations with the guy who is holding the measurement device after watching him/her for a few minutes and I'll guarantee you'll learn something.

May I also suggest parking by the fastest cars during your Auto-X weekends and making friends. You can learn a ton by talking with a fast driver who has been around. Listen and learn.

Eric

GeorgeH

iTrader: (2)

Good summary by Eric.

As for the "hows" of the adjustment eccentrics, somebody on this foum has a link to an on-line RX-8 service manual in their sig. That will tell what each eccentric does and what direction to twist it to get the result you want. Study it a bit until you understand what you are doing.

Highway8

iTrader: (11)

With the tire off the ground, you can easily see the tire move when you turn the adjustment bolts.

On the front there are 2, the front one is the camber bolt, the rear is the caster.

fastlaneracing

This is how I did it (Like Eric's first link), you can also use an Toe arm and messure with.

This is a quite good way to do it if you take your time, I wouldnt be standing in the driveway doing it.

Even if its fun and accurate I let an shop do it for me now instead. saves me time and time is money. hehe. (my hour rate at work is alot higher then a alignment shops)

For messuring Camber you just need something like this: Modify it so it will get in contact with the edge of your rims.

Eric, I liked the MKT3800 Scale Platform, that looked nice. =)

wrightcomputing

iTrader: (5)

Thanks for all you help guys the job is now complete. It took me about 4 hours as it was my first time but think I could do it again in about 1 hour 30 mins. All I used for an alignment tool was a spirit level, 2 tape measures and my eyes.
I started with the front jacked up the car and put it on axle stands. I turned the front camber bolts to get maximum camber, then looked across the wheel at the back tires and adjusted the toe until the front tires lined up with the back wheel. Repeated for both sides. I then lowered the car onto two tiles with a little bit of salt to allow them to rotate and repeated the process until they looked straight. Then checked the steering wheel which was not straight so I rolled the car back straightened the wheels and repeated after a few attempts and a few test drives I had it pretty much at 0 toe both sides. I then jacked up the back and increase to maximum -ve camber and adjusted the front arm to get 0 toe this time i jacked the car up each time to adjust then down and looked across the tire until the both lined up with the front wheels. Once I was happy I put a straight edge across both wheels and measured the distance between the front and rear of the tires they were within 16th Inch of each other so I left it at that. I checked the front the same and I have about 16th inch of toe out which seems ok.
Using a level against the tire and measuring the distance between the top of the tire and the spirit level I then used that distance and the equation Tan x = opp/adj
I worked out that I now have approximately

1.5 Degrees Negative camber on the front
2.6 Degrees Negative camber on the Back

I need to get some new tires next month so I will use his gauge to see what reading they give.

All in all a good days work and I look forward to autocross next month to see how the car feels and if it improves my time.

Team Rx8 your right about the toe and camber camber take all of 5 mins and then toe takes ages and is really fiddly.

Eric Good tips I agree completely about talking to the fast guys at autocross. I spent an hour at the end of the last event talking to one of the guys who built his car its like the lotus 7 but an American version designed by a guy in Bradenton. Its open wheeled so he explained all the parts and gave me some info so I was confident enough to do it on here.

Then the Rx8 forum is always a great place to get really good info. So thanks everyone

Highway8

iTrader: (11)

The cars natural tendancy is to understeer, having 1.5neg in the front and 2.6 neg in the rear will exasperate it. You should be able to get more the 1.5neg in the front, even at the stock ride height you should be able to get atleast 2deg neg. Try using the caster adjustment to increase neg camber in the front.

Idealy you have about 1 deg less neg camber in the rear.

Highway8

iTrader: (11)

A Much easier way of checking camber and caster. http://www.racingjunk.com/category/4...ETIC-ADAP.html

dmitrik4

iTrader: (5)

every car is different; i can't get more than -1.5 in the front of mine at stock ride height, and even that required me to weigh down the front while i tightened the upper inner control arm bolts.

EricMeyer

A couple of tricks--some easy, some not, some a little crazy.

-Most of us know that lowering the car will gain more negative camber

-Front offset bushings for the lower control arm are a great little tool to allow SAME ride height but with increased negative camber. They are easy to install and they work.

-Jack the car up after you've maxed out negative camber and kick, pull, punch, hit, judo chop the bottom of the tire and sometimes you get another .1 degree camber. If you say "Judo Chop" like Austin Powers you'll sometimes get .2

-Heat up your spindle or upright and bend it. This is an old Spec Miata trick to get more camber that is totally illegal but it works. Have somebody smarter than me do it. They both don't have to match as you're looking to get the potential for more camber and then measure it to actually obtain your target. Most people are scared of this one but you don't have to be. Most of the time people are just looking for an additional .5

-Realize that you can drive the car with less camber. You can use springs and bars to help the cars behavior. We ran about 2.4 up front and 1.9 all season last year and finished second in points. We ran a higher than most people think ride height because that is what the geometry showed was best.

-Invest in driver coaching. More often than not a road course driver (can't speak for AutoX) will go through a learning curve that has then inputting a lot of understeed into the car----driver induced understeer. Some people will try and fix this with go-faster parts, install them and wonder why they still have traces of the same problem. Guess what? Driver issue, not car issue. See it all the time. The better you can drive a car the better the feedback it will give you. Have someone much better than yourself drive your car and offer feedback. This is invaluable. I frequently have fellow racers throw down some laps and offer their .02 All your looking for are a tenth a second in a dozen corners and all of a sudden you've improved by 1 second a lap. For the most part this is about 1 or 2 mph faster mid corner speed across the entire track. Brake less, let the car roll and go full throttle to the next braking zone. Repeat process.

See you at the track,

E