This article is reprinted, in it's entirety, from the May 1988 issue of THE GRASS ROOTS MOTORSPORTS MAGAZINE AUTO-X. If you enjoy this article, please subscribe to the magazine. (800) 874-8044

Supercharged Toyota MR2

Toyota MR2 Supercharged

Is the Super-2 Too Fast to Class?

By Rob Debardeleben and Jim Pettengill

In the nine years that have passed since it's introduction, the Mazda RX-7 has won Solo II National Championships seven times in the open class and five times in the ladies' classes. Today, fast and exciting cars are being introduced so frequently that such domination by one marque is highly unlikely. This is fortunate, since such cars present the stock classification committees with an even more difficult job.

The new Toyota MR2 Supercharged is the latest to baffle the rule-makers. We have all heard of certain cars that are too fast for one class, yet too slow for another. The "Super-2" seems caught in this never-never land, leaving potential buyers' hands paused over the purchase contracts as they wait to see what happens next. The car has been classified in A Stock, the domain of the Lotus and the Porsche. If the car remains there, auto-crossing may never see a Super-2 in national level competition. If this MR2 is moved to C Stock, there could be a long line of Mazda owners at Toyota dealers.

What we will attempt to do is determine the competitiveness of the Supercharged MR2 by comparing it with a 1985 non "blown" model belonging to national competitor Gary Merideth of Orlando, Florida. Throughout the comparison, keep in mind that the suspension on Gary's MR2 has been optimized for auto-crossing and features aftermarket Tokico shock absorbers.

The Super-2 we tested, on the other hand, belonged to the press pool of Toyota Motor Sales; this means that it is the very same car used by all those other magazines. This car has had a very hard life, since some magazine testers have been known to be rather aggressive with test vehicles. It is believed our test car has seen more then it's share of the rev limiter, as well as suffering some heat tempering of the brake components. But the Super-2 should be nearly as tough as it's predecessor, with only slight exceptions that we will note later.

The drivetrain differences between the plain and Super-2 are obvious: 30 more horsepower and 40 more foot-pounds of torque are available with the optional supercharger. The maximum torque for the Super-2 occurs nearly 1,000 RPM lower, at a very autocross-like 4,000 RPM. To make the most of this powerband, a slightly wider ratio gearbox is supplied with the supercharged car.

The price of admission is extra weight. The Super-2, with an un-optioned 2,493 pounds, is 143 pounds heavier than a base '88 model - and weighs approximately 200 pounds more then Gary's '85 air conditioned stripper. The Super-2's weight distribution also suffers, with 58% (2% more then the base '88) of the weight over the rear tires. The Toyota designers could save us 40 pounds and also add some chassis rigidity by offering the Super-2 without the standard T-bar roof.

The extra mass and acceleration demands more out of the tires. The Super-2 receives an extra half inch of wheel width, which brings the total to six inches; yet the tire size remains the same at 185/60-14. It seems logical that with all this potential, Toyota would offer 50-series 15 inch tires. Oh, well! Also standard with the supercharger is an attractive but weighty spoiler and sideskirt package. The cars extra speed is controlled with the help of a new dual-diaphragm brake booster. To maintain fuel economy, the supercharger is disengaged at cruising speeds by an electromagnetic clutch and air bypass system.

The interior of the supercharged car differs only by the addition of an indicator light for the supercharger function. Our test car was equipped with comfortable, very attractive and highly recommended leather seats. These offered ample side support and, unlike many leather seats, did not leave us sliding about.

Author Rob Debardeleben pauses before taking another run on the Auto-X test course in Toyota's new MR2 Supercharged.

But enough of the dry statistics. The performance potential of this car is too tempting - let's drive!

It should come as no surprise that the first sensation one experiences behind the Super-2's wheel is the thrill of instant throttle response and acceleration. This car inspires overconfidence in commuter traffic. Darting in and out, back and forth, the new found acceleration allows the driver to squirt through holes in traffic that never before existed. The annoying mechanical whirl that emanates from behind will be dampened by a smile so big the ears will be covered. Many girlfriends will be left at the curb as America's youth passes by in a flash of bright red paint and shiny white teeth.

However, enthusiastic acceleration must be approached with caution. The Super-2's shift linkage is the culprit: the 2^nd to 3^rd gear shift is usually accompanied by an unnerving "crunch" when made at anything other then a leisurely pace. Older models have shown a weakness in the clutch and the 1^st to 2^nd gear upshift as well. The supercharged car does have a larger clutch, which should be of some help. The operative word here is kindness. Be kind to the shifter and it should reward you with years of trouble free driving. Abuse this timid child and it will never let you forget it.

Dissipating the kinetic energy produced by the supercharger is not so inspiring. Brake balance feels virtually nonexistent; the front tires seem to do all the work. A sudden, unexpected or emergency application of the brake pedal would almost certainly result in a cloud of tire smoke and subsequent squaring of the tires. Stopping this car takes great care. One must gradually apply more and more pressure, allowing the suspension to settle as the weight is transferred forward.

After completing our initial street laps, we took the supercharged MR2 and it's older sibling and headed for the Auto-X test course. BF Goodrich was kind enough to supply both vehicles with equally shaved 195/60-14 Comp T/A R1 tires; we set pressures at 40 psi cold front and rear.

Skidpad testing came first. The Super-2 was predictable and easy to navigate, with slight understeer at the limit. On our 150 foot diameter pad, it generated a respectable .86g clockwise and .89g counterclockwise. The '85 MR2 was much harder to drive, shifting from understeer to oversteer with even slight undulations or variations in the skidpad surface. This experienced competitor's better autocross suspension settings and stiffer shocks allowed the '85 MR2 to circle the skidpad at .90g clockwise and .92g counterclockwise.

Acceleration tests were approached with caution. Due to both cars' balky shifters, much time was lost between gears. The non-super car managed a time of 8.66 seconds from 0 to 60 mph, while the Super-2 took only 7.40 seconds to reach the same speed. Faster times could have been obtained, but I have a great appreciation for things mechanical.

Brake testing was much less enjoyable, with the '85 model suffering from premature lockup of the right front wheel and the supercharged car suffering from total front end lockup. Modulation was a particular problem on the new car; this was most likely caused by that vehicle's very hard life, as well as it's extra 200 pounds. The '85 MR2 stopped from 60 mph in 3.4 seconds and 130 feet, while the '88 Supercharged MR2 stopped from 60 mph in 3.8 seconds and 142 feet. Both were less than inspiring. Cars equipped with anti-lock brakes are vastly superior in stopping power, and there has never been a car that could benifit more from ABS then the MR2.

The other magazines have criticized the Super-2 for gross understeer; since this could be detrimental to autocross times, the understeer would be the would be the focus of our attention on the test course. The first real maneuver after the starting line was a slalom of five cones spaced approximately 50 feet apart. Through the slalom, the Super-2 was much better behaved than the older MR2. The older car felt twitchy, as if it was sure whether it wanted to push or oversteer. The '85 reacted unpredictability to trail-braking into the first cone, making it difficult to position accurately. The '88 car was much easier to position, and easier to hold consistant through the slalom or the lane change maneuver that occurred later in the course.

It is interesting to note that all '85 MR2's were equipped with a rear sway bar, which increased oversteer. Even Gary Merideth, owner and an advocate of the oversteering '85 MR2, said the supercharged car "feels much better through the slalom, pushes just enough."

The nature of our test facility necessitated a point-and-shoot type of course design, with short straights connecting fairly tight maneuvers. This is where the Super-2 is absolutely brilliant, putting instant power to the ground as if it were shot from a cannon. There is no doubt that this car's great advantage in autocrossing will lie in it's ability to quickly connect maneuvers.

Our test course contained two tight 90 degree, 1^st gear corners. In most cars, the second corner could be reached while still in first gear. Much steering input was required, giving the Super-2 a low-speed punch that delayed application of power. However, the second corner led onto a long straight which left the '85 MR2 seconds behind the supercharged powerhouse.

Once again, the Super-2 was fast and predictable through the next maneuver, the lane change, despite an obviously "heavy" feel by comparison. After this lane change the trigger was pulled once again, for a doglegged straight maneuver which turned out to be the fastest part of the course and which required a short shift into 3^rd gear. An informal timing trap set up just before the braking zone for the next maneuver showed only the Corvette and the Mustang LX 5.0 liter to be faster than the Super-2.

The last turn on the course required heavy braking and a downshift into 2^nd gear. This was an increasing radius sweeper. Once into the corner, both cars could be tossed into an oversteer condition, or driven through the corner with slight understeer and a steady application of the throttle. Neither car liked the tail-out attitude, whether it was natural or induced. In the oversteer situation, once traction was regained, both cars felt slower. This is a sure indication that oversteer does nothing more than scrub off speed. The only place for oversteer is in a parking lot course with turns so close together that rotating the car into position is more important than cornering force.

After our test laps were finished, we concluded that the tendency to understeer we've all heard about is indeed present in the Super-2; but on our test course, it was experienced only under heavy acceleration before completely exiting a corner. This suggests that more negative camber and a lighter right foot is all that is needed to go fast.

On the average, each driver was approximately 1.2 seconds faster on the 45 second course in the stone-stock, well used, supercharged MR2 than in the prepared '85 MR2 autocrosser. With the proper suspension alignment and stiffer shocks, the supercharged MR2 should probably be more than 1.5 seconds faster. The best time recorded by the Super-2 was a 43.6, almost on full second faster than the best time for the '85.

Let's compare these times with the '87 Solo II National Championship results. The fastest D Stock MR2 at the Nationals, with Bob Smith at the wheel, had a 149 second total time. Because of the point-and-shoot nature of our test course versus the sweeping nature of the Nationals courses, let's assume the Super-2 has a one second margin on each 45 second section over the normally aspirated MR2. The Solo National courses were 3.3 times longer than our test course; multiply one second by this factor and we have the Super-2 finishing 3.3 seconds faster than Mr. Smith, with a theoretical course total time of 146.1 seconds.

This is nearly a full second faster than Paul Kozlak's C-Stock winning Mazda RX-7, and yet half a second slower than Randy Peck's A-Stock winning Lotus Elan. Keep in mind, however, that the newer, very fast Mazda RX-7 Turbo (C Stock) is about to make Kozlak's older GSL obsolete.

The only conclusion this author can draw is that there seems to be a need for a new class, to be occupied by the high tech turbo/supercharged sports cars of the late '80s and certainly the '90s. If these new high powered two seaters are left to compete in C Stock, then many currently popular cars will become instantly uncompetitive. Think about it: if all Mazda RX-7s (Turbo and non-Turbo) must compete against each other in C Stock, then one could draw the conclusion that all MR2s should compete together, as well, in D Stock. Something is definitely not right here!

The Toyota MR2 Supercharged just may become the next dominant force in autocrossing. This car is, however, absolutely begging for anti-lock brakes. Combine ABS, a better shift linkage and a little less weight, and you'll have the best autocross car since the introduction of the Mazda RX-7.

The Toyota MR2 Supercharged is not as refined a sports car as, say, the Mazda RX-7 Turbo or the latest Corvette, but it is brutally fast in it's own efficient way. So sell the Volvo, rights to the first born, and perhaps even the project car in the garage. Then take the money and buy a Toyota MR2 Supercharged.

CounterPoint

Ken Sherman, Editor at Large

"Well, it was a long time coming. Was it worth the wait? I am both impressed and disappointed. The motor is very impressive, period. The chassis tuning is not in the right direction. This car is now too heavy and too expensive. Did I like it? Yes. Would I buy one? No. Why? I don't think the gearbox will live very long and regret the added dose of understeer and bulk."

Randy Pobst, Contributing Editor

"Incredible motor, extremely broad band of 'right now' power. Much less neutral than the '85 model. Understeering tendencies beneficial in the slalom and transitions. Brakes are powerful but difficult to modulate. Toyota has obviously tried to make this car difficult to spin, but at the expense of some of the responsiveness and agility of the earlier model. Nevertheless, I WANT ONE! And I want it NOW!"

Howard Duncan, SCCA Solo Board Member