Way back in 1985, I was in my last year of school. I was working at TRD (Toyota Racing Development) as my going through college job and I was going to graduate as an engineer in the spring of 1986. Toyota had just launched the AE86 GTS Corolla and I had to have one. Before the 86, compact cars were to a large degree, shitboxes with anemic engines. The AE86 was different. It had the 4AG 1600cc DOHC 4 valve per cylinder engine which at that time was exotic. If you wanted a DOHC 4-valve engine in the USA at the time, you had to buy an exotic or a used Cosworth Vega. With a 7500 rpm redline back when everything else revved to 5500, the engine screamed and pushed the AE86 to sub 9 second 0-60 and high 16 second 1/4 mile times. This was way faster than almost anything in the compact class and faster than many V8 sedans at the time. I think the Mitsubishi Mirage Turbo and the CRX Si were also pretty close in speed but neither of those was fun to drive RWD like the AE86, I think it might have been the last of the RWD compact cars to be sold.
Since I worked at TRD I added a bunch of N1 suspension parts from TRD’s racing catalog and some HKS and N1 engine parts. Eventually, I got the car to run in the mid-15s in the quarter mile and high 13s with a small nitrous system, remember this was faster than the GT Mustang, Corvette, Z28, and Trans Am of that time. I was also participating in track days and SCCA Solo 1 with an occasional autocross in the car. I think I even set a couple of Solo 1 lap records and came in second in points in 1987 or so. I still have the Trophy for that and they spelled my name wrong on it! The car was super fun and one of my favorite cars of all time.
A few years later someone offered me more than I paid for the car brand new and I reluctantly sold it. I regretted selling it ever since and who knew it was going to become a collector’s item? I have been looking for another 86 for the past few years but all the examples I could find were super overpriced, poorly modded, and in very rough shape. Then one day I saw that Cole Powelson of Lyfe Motorsports was selling one. I called him up and he told me it was a genuine JDM Levin with a 20V 4AG, partially stripped, fun track car that already had some performance parts on it. It was cosmetically rough but it was straight, complete, and best of all, running. Cole made me a good deal and even had it shipped to us for free (thank you, Cole!). The car sat around for a year because we were to busy to work on it but now is the time to do something with it. The idea is to make it a super fun, lightweight track car that handles and brakes well even if it is slow by today’s standards.
With that in mind, we contacted Techno Toy Tuning and they very generously supplied us with their latest and greatest modern and dare I say improved versions of the TRD parts I had used so long ago. Whiteline also provided us with a set of their excellent anti-sway bars. The list of stuff is extensive and the engineering is detailed so I am going to break it down into smaller more easily digested segments.
The first part we will be installing is a set of Techno Toy Tunings, (or T3 from now on) lower control arms. These are highly thought out, and very flexible in end-use parts. Our friend Taka Aono had a hand in their development and I being a suspension engineer saw that they have every feature I could think of incorporated in their design.
The arms are constructed of 4130 chrome molly tubing and tig welded for strength. The inner pivot bushing is replaced with a large spherical bearing to eliminate squishy rubber and reduce friction for responsive action.
One of the most important features of the T3 control arm is this spherical bearing that replaces the ball joint. It has zero compliance and low friction for direct slop-free action and has this extra long shank that allows the roll center and camber curves to be corrected on a car that is lowered a lot. On a McPherson strut car, lowering a lot will put the suspension in a position where it gains positive camber under compression, the opposite of what is desirable as gaining negative camber offsets the tire tread lift under side load and suspension tending to stand the strut up to gain positive camber as it rolls if it is lowered too much. Negative camber improves the tire’s contact patch and increases grip at the limit.
The longer shank, by allowing the control arm and outer control arm pivot point to be close to the stock position even when the car is lowered, also places the roll center close to the stock position. When the car is lowered, the roll center also drops lower, and the distance from the roll center to the center of gravity increases. This distance is called the roll couple and it acts like a lever arm and when it is longer than stock, it increases body roll. This is despite the car’s overall center of gravity getting lower by the reduced ride height. By correcting the roll center, the longer shank also decreases the roll couple, when combined with a lower center of gravity from lowering the car, the roll while cornering is reduced without having to stiffen the suspension. The tires stay planted better and with less roll and the car is more responsive to steering input.
8 comments
Kakkoii!!!
Speaking of electric power steering, why the EPS in many cars, even some performance cars are so numb? Some even feel like there’s excessive friction in the system that further muddy the steering feedback.
Not sure, you don’t have the torsion bar so it’s more direct.
Really is cool that T3 is doing what they’re doing to support a lot of old weird cars. 1st gen RX-7 lover here, which has much of the same design as the AE86, suspension-wise… actually an FB with a lot of T3 parts podiumed in E Production at the SCCA Runoffs a couple weekends ago, which is a nice testament to their stuff.
Does the AE86 do the same thing the FB does with unequal length rear links or did they do a better job there? Also be curious to see, given the opportunity to change things afforded by parts, where you’re choosing to put the instant centers in practice.
It has some different problems like a ton of roll steer and a crazy amount of anti squat so the car hops like basketballs even with the puny 4AG power.
God save us from OEMs with anti geometry.
Let’s hope for some regular updates.
Love the project and the updates! Im subbed on this for sure