Expert: Dan Liddy - 12/29/2004

Question
I would like to start by saying THANK YOU for sharing your expertise and helping me as well.  I will be welding in a roll cage next month as you suggested.

I have come to a cross roads in building my race car.  I have a 1990 Nissan 240sx.  I have to decide on how I'm going to upgrade my suspension.  I plan on autocrossing the car this summer with approx. 275 RW HP and my car should come in around 2600lbs.  
I have never raced before, a complete newbie but live near several excellent tracks here in SW Michigan.

Coilovers are supposed to be the ultimate in performance and adjustability however a set suitable for autocrossing would run between $1300 to $2200!  I'm willing to spend the money if I need to.  I'm looking at performance shocks from KYB or Tokico for around $600.  With the money saved I could spend more time on the track and even take a couple racing classes.  Most upgrades for the 240sx are intended for breaking traction (drifting) and not gripping for autocross so I'm a little lost on this one.
What are your thoughts and where can I go to find more reputable information on suspension theory and options.

Answer
Hi again David:

The best source of info I have ever run across is "How to Make Your Car Handle" by Fred Puhn ,  I think it's marketed by HP books. Your local bookstore should have it, or can order it for you, it's about $16.00.  Also you could look for it online or on E-Bay.

Coil over suspensions have the advantage of readily changable springs, and adjustable ride height.  With coil overs on all four corners, you can even jack weight around some to suit an indivudual track.

Competition shocks are the finishing touch, and also the most important part of any suspension equasion.  I'm beginning to look into the tech details of shocks now, but have nothing learned to impart as yet.   Suffice to say that some serious GT-5 racers in SCCA have $6000.00 in shocks alone. Sounds like a lot, but they are also the guys you see up front.

I think you should run a season or two of Solo events before you go to a racing school.  It will give you a better insight into what the instructors are talking about.

In my case, I ran Solos up until about 1965, then was completely away from racing until 1990.  When I went to school I was way behind some others in technique.  Now it's all good, I'm recognized as a championship driver in my region, but it was a long, long haul.

I think you'll be real happy with any advice you can get from Ground Control Products. <<www.ground-control.com>>
Just tell them what you're after.

Hope this is a help

Dan Liddy
Sarastoa, Florida