Getting Started: Chassis Tuning Knowledge

[estabahn]

I've lurking here for a while. I've been reading the last several years of General and FF/CF posts.

I've been racing production cars for the past 5 years. I want to make the transition to Club Ford in the next 12-18 months. Obviously, as I'll be just getting started, I'll need the services of a pro shop for chassis set-up [and lots of other things] :-)

But, I'd like to learn more about chassis tuning, so that one day, I can do at least some of the chassis tuning myself. What books do you suggest I read? And yes, I'm up for buying scales for corner weighting, alignment gauges etc.

Thanks!

[Dave Harmison]

There is nothing on a CFF that you can't do yourself. Personally I like Fred Puhn's HOW TO MAKE YOU CAR HANDLE. It's an easy read and has the basics. On the other end of the spectrum is Milliken, which is a graduate level book on Vehicle Dynamics. Most important, hopefully someone in the area can show you how to do things. Good luck and welcome to CFF.

[TimH]

Start by memorizing everything Carroll Smith wrote, then go from there.

[dsmithwc04]

I've lurking here for a while. I've been reading the last several years of General and FF/CF posts.

I've been racing production cars for the past 5 years. I want to make the transition to Club Ford in the next 12-18 months. Obviously, as I'll be just getting started, I'll need the services of a pro shop for chassis set-up [and lots of other things] :-)

But, I'd like to learn more about chassis tuning, so that one day, I can do at least some of the chassis tuning myself. What books do you suggest I read? And yes, I'm up for buying scales for corner weighting, alignment gauges etc.

Thanks!

I don't think needing a pro shop to set the car up for you is an "obvious" thing. If you have the funds, by all means go for it. If you pick a good shop, you may learn a few things faster. Just make sure if you do, that you are learning how to setup the car rather than just having it setup for you. Not only that, hopefully the engineer will be able to tell the difference between car setup errors and driver errors.

On the flip side, you could always do this yourself. Get a good data system (which you will need either way or else your just guessing) and log steering, lat/long G's (not calculated) throttle, RPM, wheel speed/gps, and brake pressure. That is a good starting point. Anything less then your really just looking at inadequate squiggly lines. Buy bob knox book, take john blocks webinars and you have a solid base to start from. You'll then be able to start finding errors with the setup and errors with your driving. GOOD LUCK!

P.S. You could always get into FE and share a wealth of info from exactly similar cars... Just sayin.

[dsmithwc04]

Start by memorizing everything Carroll Smith wrote, then go from there.

Tune to Win is a good one!

[Steve Demeter]

I second Carroll Smith.

While some of the actual practices may be a bit dated (outboard suspension, rocker arms and the like) the principles still apply. The laws of physics haven't changed.

If you have a follow Formula Car racer local I am sure they would be more than willing to help.

One would be amazed at how much I have forgotten that local racers taught me.

[S Lathrop]

A particular area you should study and get a very sound understanding of what is involved is aligning the suspension of a formula car. You do not need any equipment that costs more than say $50.

You need to know how to set toe, ride height, camper , caster, bump steer, corner weights and how to do all that and have the car square to itself. You need to understand how changing one variable will effect all the other variables.

You can do a search on ApexSpeed for a lot of valuable information. If you struggle with a concept, just ask and you will get many answers, all valuable for the insight they will give you.

[tonychilton]

Carroll Smiths's Engineer in Your Pocket is invaluable at the track or for just quickly getting to what the problem might be. Looked at one way it's causes like "Too much spring" or "Too little low speed bump force" with resultant effects. Turn the booklet over and it's effect -> causes like "Corner exit oversteer" or "Rough braking" with possible causes following.

[estabahn]

Thanks for the suggestions. I've ordered up Tune to Win, Engineer in your Pocket, and How to make Your car Handle. Should be some fun winter time reading

[Alex Zeller]

Something that I was messing around with last winter was using iRacing to practice the testing approach I wanted to use on race weekends.

I found this very useful and it made the thought process of setting up a racecar much more routine. I would develop a written plan of things I wanted to test and go about doing it as if I were testing in real life. Only changes can be made with a few clicks of a mouse!!! I would also make changes not so much to fix a handling issue, but to induce one. Then try to dial it out again.

I've been busy this winter rebuilding a new car but hope to practice that again in the coming months. I'm still very much an amateur but found it helpful.

Good luck and have fun!!!

[patman]

I like Fred Puhn over Carroll Smith personally, but all good reading.

You might also try "Racing Car Design and Development" by Len Terry and Alan Baker. It is not very technical but provides an interesting perspective on the thought process involved in designing a car from scratch and the way problems are figured out and overcome. It is also more in 'storybook' form, so much easier to read than the others.

If you aren't an engineer don't bother with Milliken. It is great information, but it's expensive and very technical, without much 'seat of the pants' type information.


One thing I see a lot that you might try to keep in mind is to focus on understanding the underlying physics rather than the intricate details of a particular setup. A lot of people know exactly how to find the roll center of an independent suspension, but don't have any idea what that means in terms of how the car will handle. Once you understand weight transfer, then the roll center stuff actually means something. Similarly you can read all about ideal static camber and toe settings, but if you understand the behavior they create and how to read the results, it is much more fruitful to just go to the track and do some testing.

For me, it helps to think of everything in terms of forces on the tire(s). The tire is the only interface between the car and the road, so if you can't understand how something creates a force on the tire, chances are you aren't seeing the whole picture.

FWIW, another thing that took me a long time to understand is that handling is dynamic. It isn't too hard to wrap your head around the forces on the tire at any one time based on some specific set of assumptions, but you need to think of it all the way through the corner, as springs and dampers and tires all have different time responses. Weight transfer is effectively a constant, but the speed with which the weight is transferred from one tire to the other isn't, nor is the load distribution between the tires; and controlling those two things is what most of suspension and chassis tuning is all about.