The suspension also nearly rides like a racecar. Although the suspension is barely tolerable on the smooth, well-maintained roads of the OC where we live, you would have to be very hardcore to take this sort of ride on a daily basis and it might be unpractical in other parts of the country where cold winters really tear the road up.
Bump Steer Reduction KitAlthough the EVO has a well-designed suspension, when the car is lowered, some of the geometry in the rear gets slightly out of kilter. This has to do with the location of the toe links in the back. The toe links swing though a different arc than the rest of the suspension causing the rear wheels to steer themselves as the suspension strokes. This phenomenon is called bump steer. Bump steer can make the car feel twitchy in the back at the limit and under trailing throttle.
To reduce the rear bump steer we installed Whitelines bump steer correction kit. Whiteline is an Australian company that has an impressive array of suspension components for many Japanese cars such as Honda, Toyota, the WRX, Nissan S13/314 and Sentra SE-R. Whiteline also has many geometry correcting kits for cars that need it, an unusual detail for a suspension component manufacturer.
Whiteline's bumpsteer elimination kit for the EVO relocates the position of the inner pivot of the tie rod upward. The kit consists of a urethane bushing with an internal eccentric. This puts it at a more favorable angle so it does not allow the toe to change much as the suspension strokes. This simple and inexpensive part makes Project EVO much more predictable, especially in bumpy turns.
Once our revised suspension parts were installed we took Project EVO to West End Alignment to have Darren Nishimura work his magic. Darren set our front camber at 2.5 degrees negative and the front toe slightly out. The rear camber was set at 1.5 degrees negative with zero rear toe. Darren also set the corner weights for zero cross weight with 200 lbs in the drivers seat.
Different Wheels and Tires
We had bought some wheels and tires for another project but the trouble was they did not fit! On a whim we tried them on project EVO and they fit perfectly. Not wanting to waste a perfectly good set of wheels and tires we left them on the car for the time being.
The wheels are bronze anodized 18x8.5 Rays Gram Lite Fs with a 30mm offset. These are ultra light one-piece forged wheels tipping the scales at just less than 18 lbs. We like their simple thin- spoke styling. The tires are Michelin Pilot Sport 2, sized 245/35-18. The Pilot Sports are considered to be one of the premium ultra high-performance tires around. Their dry grip is on par with our BFG KDs and they are better in the wet weather we have been dealing with in Southern California lately. Perhaps the KDs had a tiny bit more grip at the limit on dry ground but the Michelins had a tad better transient response and definitely more wet grip.
Driving Project EVO is interesting. The EVO is now clearly track biased in its manor. The ride can be punishing but it gets better the harder the car is pushed. Fast rough turns are now gobbled up with loads of wheel travel; even at the cars low ride height. Before the car would wallow and hop, now it stays planted and the power can be put down hard.
Even though the Hyperdamper Pro suspension has a more frontward bias in the spring rates than the Hyperdamper II or even the stock suspension, the car has less understeer than before. Essentially the car is still neutral but the tendency is for the car to now four-wheel drift, leading with the rear wheels instead of the front. This is better for getting around a track quickly.
The old suspension would touch the front snubbers when pushed real hard in a turn. This would make max effort cornering end in grinding understeer, a safe mode for beginning drivers but not the fast way around. With the Hyperdampers ample travel and stiff spring rates, this does not happen and the front wheels seem to find traction better.
With the higher rates, we find that detectable body roll has disappeared. With the elimination of bumpsteer, the rear of the car is very easy to catch and hold in long beautiful slides. We also like the fact that the dampers and the sway bars are baseline good when set right in the middle settings. This is a good help for tuning the car for specific tracks and conditions. We have a lot of adjustment leeway to go either way. Now it's time to up the power ante again.