ITB racing(Suspension ect)

[gary keller]

Does anyone out there know what a good spring rate would be for the rear springs when racing Itb class.And does anyone know what the sport front leaf spring is rated at?I would like to maake asjustable camber but the plate I slotted out for the ball joints are way to sensitive to a minute ajustment. Anybody ever have any luck with fabricating an ajustable suspension/
Thanks,Gary Keller

[Gary]

Gary - Try the site search feature using "spring rate" or "adjustable camber". I think there's a lot of info already posted on those topics. The program this site runs on has a very powerful search engine that sifts through the 22,000+ messages is seconds.

[RallyBob]

Originally posted by gary keller
Does anyone out there know what a good spring rate would be for the rear springs when racing Itb class.And does anyone know what the sport front leaf spring is rated at?I would like to maake asjustable camber but the plate I slotted out for the ball joints are way to sensitive to a minute ajustment. Anybody ever have any luck with fabricating an ajustable suspension/
Thanks,Gary Keller

The rear spring rate depends on the front spring rate you are running. I think you'll have to contact the supplier of your spring to find out the rate.....they are not all the same from manufacturer to manufacturer, and I know from experience that there are at least three companies that have made them for GT's, with various models from each company.

But for comparison, I used to run a 500 lb fiberglass front leaf and a 200 lb rear coil set for ITB GT's. The steel sport spring I used to sell was 370 lbs, but because of the binding issues with this sort of spring (not as bad as the stock spring BTW), rear spring rates should be closer to 225 lbs to compensate.

This is all assuming you have left the rear roll center 'as is'. Chances are you will change the panhard bar location, altering the roll center height. So you will have to change the rear spring rates accordingly.

Now as far as making the GT alignment adjustable, it is not difficult to do. The issue is that most methods are illegal per the IT rules to do to the GT. No cutting, welding, etc. Offset suspension bushings are the normal method most people use, or in the case of a strut type suspension.....camber plates.

You might be able to 'get away' with cutting and welding, etc, depending on your region's tech guys, but you have to be the judge of that.