Note: if you have not read my previous posts, I suggest you to start with the Part 1.
On the first and the second part of “Fixing the driveability issues” I was concentrating my efforts to correct erroneous suspension geometry. Now, when the suspension geometry was set up correctly, I shifted my focus to both tires and rim offset.
Part one and two were just the basic stuff. Most of us do understand the importance of fixing camber and toe. But for some reason, most of use are neglecting the importance of tires and rim offset.
If you think about what single component is responsible in between your car and road, it should be quite obvious that optimizing the tire quality will give you the best bang for the buck. I mean seriously. The best possible performance upgrade for your car is not 20 000 euros suspension kit. It is tires. Period. The quality of rubber compound makes the most difference. It does not matter how wide your rear tires are either, if their compound is not up to the task. Good semi slicks in 225 size will beat any budget tires in 275 size. Anytime. The difference of tire compound quality is huge. You just don’t believe it – until you will try it out.
In order to improve handling characteristics even more, I decided to change the rim offset a bit. The rims are very rare and good looking RIAL mesh style in 8×16″ size for front and 9×16″ for rear. The front ET was 13, and it made the steering a bit nervous, thus I ended up machining 2 millimeters from the rim center. So the front ET was increased to approx. 15. Believe me or not, it made the difference. The rear ET was also increased to 15, due to a clearance issue with Toyo Semis. This issues was present with rolled fenders. Rears in 225/45/16 size with 9″ rims and ET15 are pretty tight fit for stock E30.
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