Category: Our racing exploits

June 12-13, 2010

We started building our ITA Mazda Miata in 2007. Little did we know it would be more than three years later, on June 12, 2010, before the car would claim an SCCA Club Racing win. The following day, the car took home its second victory.

Neither race was easy. Local ITA competitor in a first gen Mazda RX-7 usually destroys our little Miata. In the past, we’ve been competitive in the braking zones and through the turns, but we always found the Miata’s acceleration a little lacking. The acceleration issue – or, more accurately, the lack thereof – is usually amplified at Auto Club Speedway in Fontana, Calif., due to the speedway’s long front straight. Ironically, Auto Club Speedway was the location of our Miata’s first two wins.

Did we add more power? Nope.

In a previous installment, we covered the addition of a front spoiler, under tray and the removal of the Miata’s side mirrors. Those all aided in making the Miata slip through the air with more efficiency, but we didn’t think that would be enough to get the job done. So with a week to go, we decided to re-gear the car.

Per the Improved Touring rules, cars may install any ring and pinion as long as the gears fit in the factory housing. Our 1996 Miata came with a 4.10, but we changed to a 4.30 when we installed a Torsen diff. At auto Club Speedway, however, the 4.30 would top out at between 116 mph and 118 mph, usually in fourth gear – fifth gear would result in a speed decrease. Swapping to a shorter final drive would lower the theoretical top speed, but increase the car’s ability to get there.

A popular gear set to use for Miatas is the Mazdaspeed 4.8 ring and pinion. The cost for that gear set is just under $400 through Mazdaspeed’s parts program. Unfortunately, the part was backordered. Then we got lucky.

While perusing a forum, we found someone selling a 4.77 ring and pinion out of a Kia Sportage. Apparently, a hot modification in the Honda S2000 world is to install the Kia gears into their Hondas. A little more research revealed that the 4.77 was also used in some Mazda RX-8s, and we knew from experience that the RX-8 ring and pinion was a direct bolt in to a first and second generation Miata. If “A” equals “B” and “B” equals “C,” then by our calculation the 4.77 should fit our ITA Miata. We bought the gear for $250 shipped and gave it a shot. And wouldn’t you know, the 4.77 fits perfectly.

While we haven’t tried them, we did discover that the Kia Sportage has a variety of aftermarket gears available to replace its 4.77, including a 4.87, 5.13 and a 5.38.

With the 4.77 installed, we could now hit 118 mph to 120 mph in fifth gear, spinning the motor to just over 7,000 rpm. The 4.87 gear might be usable in our Miata, but we know the 5.13 and 5.38 would be too short.

Because a weekend wouldn’t be complete without completely changing the car’s setup setup, we decided to test some new tires, so we ordered a set of new Goodyear RS R-compound tires. In fact we ordered two sets: 205/50-15 and 225/45-15. Not a lot of people are racing on these, but we’ve heard they’re as sticky as a Hoosier R6.

We also removed the Racing Beat rear swaybar and installed the 11mm stock rear swaybar.

By the end of the weekend, we’d won two races, one on the 205s and one on the 225s. As of this writing, we’re still sifting through the data to find the advantages and disadvantages of the two tire sizes – but the reality is, the car was fast, both races were won handily and we were very happy with the tires, the gearing, and the front splitter.

Our Miata is now going to sit dormant until the 2011 season, where it may reappear with “STL” decals rather than the familiar “ITA” ones.


May 2, 2010

For the first time in about a year, SportsCar mag’s ITA Miata emerged from its cave in preparation for the June 12-13 SCCA road race at Auto Club Speedway in Fontana, Calif. It’s one thing to prep a car in the garage, but actually putting the car in a performance environment really tells the tale of if there’s anything wrong – so we loaded the car on the trailer and towed it to El Toro for the Cal Club Region Solo event on May 2.

The weekend went well. Sure, we finished fourth out of five in C Street Prepared, but the weekend revealed that while our car has been sitting for an extended period of time, it’s still running strong and is ready to tackle the forthcoming road race.

Here’s footage from the final run of the day. This run was good enough to put us 0.1 seconds off third place, which was an honest-to-goodness CSP car driven by someone who knew what he was doing.

April 24-25, 2010

What a difference a weekend makes. Heading into the SCCA Double National hosted by Cal Club Region at Buttonwillow Raceway Park in Buttonwillow, Ca., the SportsCar staff had one goal: finish. That may not be flashy, but to get an SCCA National Championship Runoffs invitation, you have to complete four National races. Entering this weekend, SportsCar’s Associate Editor Jason Isley had three races logged in the magazine’s H Production Toyota Yaris, and Editor Philip Royle had two finishes in the Showroom Stock C Nissan Sentra.

As usual, the Yaris attracted attention from the moment we rolled into the track. Sporting its new, Dan Gurney- inspired Toyota Eagle graphics, the car was a looker.

Saturday’s qualifying session found Isley starting second in HP with Royle third in SSC. When the green flag dropped on the 34 car field, both Isley and Royle, along with a number of other cars, found themselves trapped behind an American Sedan car. After a couple of laps and many attempts, Royle made the pass stick, and he set to running down Ali Naimi and Brian Husting, who were running first and second in SSC. Unfortunately, Naimi and Husting had managed an insurmountable lead, so Royle maintained the gap between himself and fourth place SSC competitor Carl Young and brought home a third place finish.

For Isley, Saturday’s race would come to an end three laps in when a mechanical failure caused the Yaris to make contact with a tire barrier. The front of the Yaris was damaged, although most of it is easily repairable. Isley reported that when he made contact with the tire barrier, he felt his Hutchens Hybrid Pro head and neck restraint work, limiting the forward movement of his HJC helmet during the impact.

With one car now in need of repair, Sunday’s race plan was to take it easy in the Nissan – qualify for the Runoffs then get to work repairing the Yaris for the next National race. However, Husting was struggling with transmission problems, and as soon as the green flag flew, Royle saw an opening and went for it. After a few laps of hounding Husting, Royle made the pass for second and set to pounding down solid laps, hoping first place Naimi would misstep. Three laps in, Husting and Young tangled in the esses while battling for third, and Young’s car flipped, coming to rest on its side. A full course caution bunched the pack. After the restart, Royle kept Naimi in his sights, but Naimi maintained the lead to the checker. Royle’s second place finish continued the SSC Nissan’s record of never finishing off the podium.

We learned many things from this race weekend. First and foremost, safety equipment should not be taken lightly – even when your goal is simply to log a finish, you never know what will happen. For the Sentra, the BFGoodrich R1 tires worked great in 80 degree F heat. They were consistent, with only minor fade by the end of the races. The Hawk DTC-70 brake pads performed admirably and are undoubtedly the correct compound, but on a 3,100 pound car, the life of the pads is limited to two or three races.

With the close of this weekend, Royle locked in his Runoffs invitation. Isley, however, will be heading to another SCCA National to cement not only his Runoffs invite, but also hopefully a Southern Pacific Division HP points championship.

And finally, we’d like to thank the Team Honda Research crew for their help at the track – without their assistance, the Nissan’s weekend would have been a struggle. Also, we’d like to thank John Coffey for his assistance with the Yaris, as well as the kindness of strangers who helped push the Yaris onto the trailer on Saturday evening. We’d also like to offer a massive thank you to the Cal Club Region workers and safety crew for their excellent help rescuing not only our Yaris, but also the suddenly stranded Isley.

Highlight video from the Sentra.