1997 Mazda MX-5 Miata: The Beauty Of Dual-Purpose Cars, Pt. III
July 14, 2011
By the time we'd reached Highway 101 on our mountain-road-and-track trip, the ambient air temp had dropped considerably. I'd been able to use the throttle with impunity for the last several miles as a consequence, and we'd had a hell of a great drive so far, earlier near-overheating notwithstanding.
Carmel Valley Road was our final tarmac destination before turning in for the night. It was nightfall when we reached the turnoff for this road, a bumpy, tricky, tight mess of an unlit 23-mile stretch. I absolutely love it to pieces. But it's no place for some rickety 15-year old droptop.
Carmel Valley Road brings out the worst in a chassis. It has everything, sometimes all at once -- off-camber, broken pavement, scree-strewn, decreasing radius blind corners. If your car isn't right, this road will let you know about it in no uncertain terms. Insufficient travel, poorly valved dampers, mismatched spring rates? You'll hate this road. This is an Evo or WRX road.
And you know what? Project Miata swallowed up that bumpiness and fidgetiness while being driven as hard as the headlights would allow, maintaining its grip on the pavement with the security of an iron fist. No amount of pounding would upset it. It remained poised, communicative and inspired heaps of confidence. I'd been impressed with its bump compliance before, but this road is kind of an ultimate test. Project Miata is no Evo, but it's doing a far better job of emulating one here than a 15-year old droptop has any right to do. Gotta hand it to FatCat Motorsports, they know how to dial a suspension for this stuff, and that's not easy.
That suspension works even better now that Project Miata's chassis stiffness has been fortified by the GT3 6-point roll bar. I'll go so far as to say that the car has been transformed by its presence, with the brunt of the credit going to its door bars. Much of the secondary jitteriness the body shell had while traversing bumps is now gone; the whole thing drives more all-of-a-piece. It now goes down the road like a fundamentally much more serious and capable car.
There's more. Project Miata's ride quality is notably more supple due to the roll bar. Inputs from the road can actually be damped out by the suspension, rather than simply being transmitted to the previously noodly (and undamped) chassis. Whether increased chassis stiffness improves lap times is one of those endless internet debates, but consider this -- allowing the suspension to work better results in more uniform contact patch loading when traversing lumpy pavement. It also makes for a much more confidence-inspiring (and pleasant) drive. Confidence is speed.
One side effect of lowering a Miata (or any car, really) is bump steer, and Project Miata has exhibited it from the day we did exactly that. The bump steer was excessive at times on Carmel Valley Road. A million years ago I'd swapped in the longer tie rod ends from the R-package cars. A good start, but longer tie rod ends alone aren't really enough to quell the bump steer at the ride height Project Miata runs. I should fab some spacer shims to move the steering rack up. I probably won't.
Fun roads over, we turned up Laureles Grade and onto Highway 68 to find a hotel. Motel 6 only has smoking rooms available. Screw that. Days Inn it is. We'll rise with the sun (not really) and arrive at Laguna Seca in the morning, all bright-eyed and bushy-tailed (not really).
--Jason Kavanagh, Engineering Editor