Power Upgrade Payoff

Update by John Rogers to the Mazda MX-5 Miata project car
Jul 22, 2010

We're ready for battle.
Project STR sits in parc fermé, allowing competitors to inspect the car--and wonder how it goes so fast.
Totally tubular: This nicely welded header features a high-flow catalytic converter that retains all of the O2 sensors.
A PPE midpipe features a straight run for exhaust gases, streaming through another high-flow catalytic converter.

Our 2010 Mazda MX-5 autocross project continues to evolve. Between the Peru National Tour and Toledo ProSolo events, we focused on adding some power to our car.

Battles for the top positions in the SCCA’s Street Touring Roadster class are turning out to be intense, with just a few tenths of a second separating the trophy positions at most SCCA National-level events this season. The Toledo ProSolo was no exception, with the margin of victory for Project STR driver Chris Harvey at a scant .087 second over runner-up Jason Wong in his well-prepped Honda S2000. Just .389 second back was David Corsaro, piloting his Honda S2000 CR to third place.

Our MX5’s acceleration and throttle response was recently improved with the addition of a PPE Engineering header and midpipe. Enhanced exhaust flow and power were found throughout the rpm range, yet they stayed within the confines of the SCCA class rules. We shaved a few precious pounds off the car, too.

This newfound acceleration made all the difference for Project STR at the Toledo ProSolo this past weekend. Look for a complete rundown of all our power enhancements in an upcoming issue of Grassroots Motorsports.

Along with finding ways to make the car go faster, another fundamental part of this project is keeping the car streetable. To that end, our driver, Chris Harvey, drove 250 miles to and from the event on the same tires and wheels he raced on—just like we did for the Peru National Tour two weeks earlier. No tire changes were needed. The rest of our gear for the weekend was packed into the car. Chris’s only complaint: what to do with all of his spare time at the event. Could going fast get any easier?

Join Free Join our community to easily find more project updates.
View comments on the GRM forums
7/22/10 2:19 p.m.

Congrats on the win at the Toledo Pro Harvey! Any idea what kind of power gains you got from these recent upgrades?

racer_ace Reader
7/22/10 10:42 p.m.

Congrats on the recent event win! I must say that I have not been to keen on the 3rd gen MX-5s styling. The recent nose update helped. In the quest for auto-x speed you have totaly transformed the MX-5s appearance. Project STR's stance and huge meats transform the appearance of the car. It is sharp!

7/26/10 12:53 p.m.


We haven't had time to get the MX-5 on the dyno, or run our standard rolling acceleration test. PPE says the gain is just over 10hp. Competition has been tight, so we'll take every bit we can get.

7/28/10 11:38 a.m.

Thanks for the answer John!

Sponsored by

The Tire Rack

Our Preferred Partners