2002 Acura RSX-S Handling Analysis

Car Setup:

• Kumho V700 Vitoracer 225/50-ZR16 on stock 16"x6.5" wheels
  • Final tire pressures used: 36F/35R
• Carbotech Panther+ front brake pads
• Motul 600 brake fluid
• Redline WaterWetter coolant additive

Introduction

It's not very easy to get an idea of how well a car is able to handle at its limits on the street. On the track, however, any weaknesses are greatly magnified. I am happy to report that the RSX Type S has very few weaknesses. In fact, a better word for the minor shortcomings might be "compromises". The reason I choose this word is because the car is not carrying Honda's "R" moniker, designating the utmost factory available performance. In Type S form, it is designed with the mindset that the average driver is going to drive it enthusiastically on the street, occasionally detouring down twisty roads for a bit of an adrenaline rush. When they're driving it to and from work, however, they generally don't want a harsh ride while they're sipping a latte and talking on the cell phone. Enter the Type S model, a compromise between the Type R and base models.

Preparation

A huge downfall with the RSX-S is the stock tires. The Tire Rack classifies the Michelin Pilot HX MXM4 as a grand touring tire. As with past Integras (except the Type R, of course), Honda has chosen possibly the worst tire to pair with this vehicle. I am almost embarrassed to drive these Michelins on the street since they howl when pushed beyond anything my grandmother would try. I bought a second set of factory wheels to mount the Kumho competition tires on. The stock wheels weigh in surprisingly light at only 16 lbs. each. Comparable, inexpensive aftermarket wheels weight at least 1 lb. more. Seeing as I could buy stock wheels (with low mileage stock tires still mounted) for $100 each shipped, it made sense to do so. Once I had the wheels, I mounted a set of Kumho V700 Vitoracers from the Tire Rack in 225/50-ZR16 form.

To prepare the car for high-speed track duty, the brakes were the next area to look at. While the stock pads work fine on the street, there was no way I was about to trust them in repeated braking from speeds over 100 MPH during the course of a weekend. I opted for Carbotech Panther+ pads based on notyper's recommendation. I had never tried these before, but I was told they performed similarly to Porterfield R4S pads, which I had used with great results on my Integra. In addition to the pads, I needed to make sure the brake fluid could stand up to the excess heat that was going to be generated. I looked to Motul for their tried-and-true 600 racing brake fluid. It is DOT 3/4 compatible with very high boiling points, and it has worked well for me in past applications.

Driving the RSX Type S

The suspension tuning on the RSX-S seems to be quite good. It handles transitional maneuvers very well, as evidenced by autocross slaloms and S-turns at the track. The shocks and springs are matched well in that the car's body motions are controlled and able to keep up with the steering inputs. The car takes a nice set in corners and has good compliance under heavy loading over slightly rough surfaces. This was noticed when coming off an 18 degree banking to the flat spot of the track in a left hand corner at over 100 MPH; the car didn't flinch, although my kidneys would have preferred a lower speed. Although it had been a while since I had driven the Integra on a track, one of the first words that came to mind when entering a corner was "solid". The chassis with the new RSX is much stiffer than the previous Integra. Combined with pretty beefy swaybars (23mm F/19mm R), the RSX has a fairly low amount of body roll.

The RSX-S uses the same size brakes as the S2000. In a car that weighs almost 50 lbs. less, the RSX has more than ample stopping power. This is not shown by any magazine braking test numbers because the stock tires are terrible. Add wide competition tires and brake pads, and this car can be halted very quickly. Compared to my previous Integra where using 100% of the stopping power left a little more to be desired, the RSX has enough clamping force in the binders to make your passengers worry. I did notice that in using the stock rear pads instead of also upgrading them to Carbotechs, they showed uneven wear at the upper and lower edges of the pads. This is due to overheating, and I will need to get different pads for the rear for future track events.

What about the "compromises" I mentioned earlier? Let's talk about them. Remember, I'm using 225 width competition tires with a more aggressive front brake pad. When hauling the car down hard from speed, the tail end of the car dances around a bit. The harder I got on the brakes, the more prominent this effect. As soon as I came off the brakes, the back end stuck like glue. This would indicate to me that the car is nose-diving a bit too much upon braking and unloading the rear. I tried to keep the fuel tank full in an effort to reduce this effect, since braking hard from over 100 MPH and having the back end dance around is not the most comforting feeling. How to fix this? I would like to add a coilover suspension, which would provide stiffer shocks and springs and also allow me to reduce the ride height by an inch or so. This should drastically reduce the braking induced dive, thus reducing the weight transfer from back to front. This will (hopefully) diminish the tail wagging effect under braking. An obvious benefit will be reduced body roll and increased grip at the penalty of a slightly harsher ride.

Another note on the handling is the lack of negative camber. On day 2, I increased the air pressure in all 4 tires by 1 PSI in an effort to keep the tire a bit flatter. The tires appeared to be rolling over a bit too much by the end of day 1. The factory spec on this car is 0 degrees of negative camber in the front and rear. Although I have not yet tried, -0.25 degrees of front camber is possible in factory form. With the change to "crash" bolts (smaller diameter bolts that connect the strut to the spindle), up to -0.75 degrees is possible for about $4 per bolt (4 are needed). This should help cure the rolling over problem a bit, which will even out tire wear and increase turn-in response. The rear camber should be adjustable by adding shims, although I have yet to research this. A camber kit could be added for an additional cost.

The seats in the RSX are designed by Recaro. However, since Recaro wanted to charge Honda an arm and a leg to have the Recaro name stitched into every seat, they look like typical factory seats. The seats are quite good, providing a good deal of lateral support. The problem is that leather is slippery. And since the side bolsters are not adjustable, my athletic 165 lb., 6'2" frame has a couple of inches to slide before hitting a side bolster. Using a stickier material (Gen3 Integra Type R seat material comes to mind) and providing adjustable side bolsters would cure this problem. I found myself using my left foot on the dead pedal to brace myself. The seats are probably better suited for a wider driver. I did have the chance to sit in a new Civic Si and try it's seats. They seemed wonderfully supportive and used a stickier material. It may be possible to switch the RSX seats with Si seats.

An LSD would be nice on this car. I would use it in everyday street driving, but it would help immensely in autocrosses and also in road course driving. Transferring the power to an outside wheel would allow the car to be able to power out of corners a bit harder by using more available grip. In autocross, it is easy to spin the inside tire coming out of a corner. The corners on a road course are generally not that tight, but an LSD would help in powering out of lower speed corners.

The only other minor quibble I have with the RSX-S is the rev limiter at about 8200 RPM. There were 2 corners at Texas World Speedway where I didn't have enough room in 3rd gear. If I were to have the JDM Type R redline of 8500 RPM, I might have been able to hold 3rd gear rather than be hitting the rev limiter or getting stuck in 4th. This is a very minor compromise, though, and may not even be a problem on a different track.

Conclusion

Overall, I was very impressed with the RSX Type S in a road course environment. It remained very composed through 99% of the 200 miles of track driving it was subjected to. I was able to drive this course faster in this car in stock form than I ever could in my Integra with aftermarket shocks and springs. Some of this is increased experience, but much of it is the car. The light rear end under braking needs to be worked on, but I doubt this is a problem with the stock tires and front brake pads; using these brake pads at full operating temperature on the street makes the stock tires very angry. Until I was able to get the RSX on the track, I was in a constant state of wonder if I had purchased the right car for my needs. After this weekend, all of those wonders have turned into certainties: this car is an excellent performer on the street or track, no questions about it.

Hits:

• Great gearbox
• Good suspension tuning -- minimal body roll, lots of grip
• Good torque exiting corners

Misses:

• Twitchy rear end under heavy braking
• Needs some negative camber
• More supportive & less slippery seats
• Would like 8500 RPM redline

Copyright 2002, Temple of VTEC