Tom Wilson
June 1, 2007
Photos By: E. John Thawley III
Nearly anything goes in NASA's American Iron Extreme, but so far, the car of choice is the Mustang. Paul Brown leads the way in his new AIX racer sporting his Tiger Racing carbon bodywork and ex-World Challenge 351 small-block power. Patrick Lindsey's American Iron Fox was a last-minute addition to AIX at Mid-Ohio-he finished Second in the AIX championship round. Look for this car in American Iron in 2007. Just to prove anything goes, Paul Faessler's first-generation Mustang came out of NASA's now-obsolete AI Vintage class to nearly win the AIX championship. He was taking the race to Rocco when a broken valve stem put a tire down, ending his drive. Built by Paul's Automotive Engineering in Cincinnati, this coupe will be a force in AIX.

Horse Sense: Under-tired by design, AIX cars inherently provide the stage for a superior driver to shine. Similar to Super Street Outlaw drag cars, AIX racers would benefit immensely from a true racing chassis and huge racing slicks. It would also ruin the class.

All of us in the 5.0&SF magazine family are power junkies. When it comes to racing where the chassis is king, horsepower still sings the siren's call. So there's little doubt why we're looking at American Iron Extreme this month. It's the most powerful, wildest outlet for Mustang enthusiasts with a bent for corners and four-digit power ratings. Where else can you race a Mustang with no limits on displacement and power adders are welcome?

That's the sort of thing we've come to expect from the National Auto Sport Association [(510) 232-6272;]. Approaching sanctioning as a business rather than a club, NASA's philosophy is to embrace the aftermarket and its ready-made supply of go-fast parts. The same stuff you're buying for your street Mustang is the same stuff NASA expects you to run at its races.

You can buy a lot of stuff by the time you reach AIX, which is the pinnacle of a three-level class structure. To start is NASA's Camaro-Mustang Challenge and CMC2 for S197 Mustangs and LS1-powered Chevys. Here, the powertrains remain stock-all the way down to the crimped factory headers-with simple spring, sway bar, and shock chassis improvements. The class is well subscribed, and the cars are excellent teaching tools as they're traction-limited with smaller tires and torquey engines.

Paul Brown was the fastest at Mid-Ohio and could've easily won the AIX championship, but a last-minute engine change meant he started the race three laps after the green flag dropped. He unlapped himself once, set the fastest race lap, and finished Sixth. With seven years driving and prepping Mustangs in the World Challenge, Paul is likely the most experienced racer in the AIX field.

Next is NASA's most popular Mustang class, American Iron. Here you'll find a larger gaggle of pure-race Mustangs and a few Camaros sporting a spec Toyo tire, modest fender flares, and whatever engine mods work to be within a 9.5 pounds per horsepower limit. NASA uses a chassis dyno to verify the horsepower; in practice you see something with more than 300 hp and cars on both sides of 3,000 pounds. Suspension mods are fairly liberal, and these cars are plenty fast and fun to drive. We've driven several and they're precise, satisfying race cars that'll hold your interest for decades.

When "plenty fast and fun" isn't enough, there's American Iron Extreme. Conceptually, AIX is AI without the power-to-weight limitation. The idea is to limit the expense without limiting the modifications. That it results in road-racing rockets and should soon yield something akin to pod racers doesn't seem to bother anyone.

NASA's ingenious rules are written to be as free as possible, but with a few important choke points. In AIX any transmission is legal, but it must be readily available at no more than $6,000 retail. Any brake, fender flare and nearly any suspension is legal, but the maximum wheel size is 18x11 inches; only DOT-approved tires may be run and traction control isn't allowed. Even though any gasoline-burning piston engine can be run, all power adders are allowed except for nitrous, and displacement is unrestricted. You can see there is only so much grip available and only so much power can be run through a $6,000 transmission on a road course. But it's still a lot.

It's good to be number one, and Ernesto is enjoying his year as AIX champion. The ex-mountain bike racer is in excellent shape for driving these hot, noisy, high-g race cars.

Other noteworthy technicalities are a minimum weight of 2,700 pounds with driver, the floorpan or unibody must remain intact, the firewall may not be relocated, shock towers must remain in place (although they need not be used), and there is a minimum 100-inch wheelbase requirement. A rear wing may be run but is limited in size and setback, and no car older than a '60 is allowed. Neither are foreign cars-this is American Iron Extreme, after all. Fox and SN-95 Mustangs are favored because they're inexpensive, adaptable, and available. Early adopters can run S197 Mustangs, but they're heavier than the earlier cars, which are stiffened with a rollcage. The weight negates the S197's chassis rigidity advantage it enjoys on the street.

For the record, Corvettes aren't allowed as they don't have a back seat, Pintos aren't long enough to qualify, but the new Pontiac GTO is legal. So are old Valiants, Falcons, Camaros, Darts, Mustangs, Novas, and so on. Remember, any engine-turbo 2.3 to Cosworth DFV F1 V-8 to a Keith Black Hemi-can be put in any legal chassis.

When Ernesto Rocco's race engine failed at Mid-Ohio, Ford Performance Solutions lent him a warmed 347 they had on hand. Ernesto said it had maybe 450 hp at the flywheel. Whatever the number, it was small potatoes compared to the 1,200 hp he hoped to unleash at Ohio. But in Ernesto's highly tuned chassis it was enough when Paul Brown began late and Paul Faessler faded. The people at FPS gave him the 347; they must've figured it was worn out anyway.

Right now Mustangs dominate AIX, but everyone agrees the top car has yet to be built. Opinions vary on what that would be, but reasonable thinking foresees a moderate displacement, a relatively slow-revving small-block with twin turbos, the industry-standard Jerico transmission, and a carefully built chassis with 315/18-inch tires on all corners. The combination should prove reasonably well-balanced-which is the key to road-racing success-yet unpassably powerful down the straights while retaining working reliability.

It was said it would take 1,200 hp to prevail in AIX; at least that was the consensus going into NASA's first national championship races at Mid-Ohio last fall. In reality, Ernesto Rocco claims it took less than 400 rwhp to win the AIX championship after his own race engine went south, Paul Faessler had a flat and Paul Brown started three laps down. A bit more than 600 flywheel horsepower is typical of AIX front-runners as we go to press. Still, this class is in serious flux, with power levels rising to 800 hp this year. The 1,000hp road-racing Mustang is sure to debut before long. What a ride that will be.

So far we've driven one AIX car, Bruce Griggs' "Old Blue" ("Extreme Winner," May '05, p. 200). Running right at 600 hp and benefiting from the latest Griggs A-arm front suspension, 315 tires all around, and every other trick in the book, we found the "number 40 car" enchanting and terrifying. This was thanks to a willing chassis that carved a line unlike any of the several hundred Mustangs we've known, as well as a combination of Hand of God thrust with the inevitable doubt introduced by a DOT tire and not exactly a full tube-frame chassis. Bruce said it best when he opined these cars are "so fast they aren't fun any more." We agreed, recalling that no matter what we did, we couldn't bring ourselves to use all the throttle in some of the faster sweepers. The car was able, but we needed more time to jack up our courage.

Patrick Lindsey's car may look familiar, as it appeared in these pages when Ryan Flaherty ran it in AI. Patrick added it to his collection, which includes an '01 Audi S4 he runs in NASA's Performance Touring. When Ryan had the car, he ran Maximum Motorsports' suspension under it; Patrick replaced it with Griggs Racing gear, including an SLA. After the Mid-Ohio championship race, Patrick crashed the car at a California event. It was unclear how much of a factor the car would be in 2007.

Will it take 1,000 hp to win the AIX championship this year? No, but we wouldn't bet against someone trying it. The trick is getting a DOT tire to handle such power. DOT race rubber is good, but it doesn't offer the precision of a dedicated racing slick. On AIX cars, they aren't large enough to handle such power except on the top half of the longer straights. But if everything else is working and the driver can drive with the sensitivity of a brain surgeon and hit the warp drive on a long straight, then he's going to be tough to beat. It'll likely take the 335 series tire, something no one has run yet.

Of course, it'll take a real hero to wheel such a thruster to victory lane, someone who's an ace at tire management. As an amateur class, AIX is populated by a diverse group of drivers and tech types. Champion Ernesto Rocco is a computer programmer during the week and a one-man racing team the rest of the time. He does it all himself, from driving the motorhome to making lunch, wrenching, and driving. Ernesto has also honed skills as a chassis man and makes money setting up other racers' cars. He has the wherewithal to get his car working well. As champion, he's scooped up major contingencies from Griggs and others. He also scored Amsoil and Hoosier sponsorships. As always, the least expensive way to race is racing to win.

An even more pure-bred racer is Paul Brown. Racing and car prep is all Paul does, and he has experience in a variety of high-powered machinery besides his newly built AIX car (a Ferrari 512 at Le Mans, for example). Paul also raced Mustangs in World Challenge for seven years. All this makes him a dangerous man, and one we'll certainly watch in the 2007 championship.

Paul expanded his inventory of old World Challenge engines last year in a flurry of valve failures, and he was rebuilding them to around 550 hp as we went to press. Paul's SN-95-based chassis employs a Frankenstein combination of a Grigg's torque arm and a Watts link in the rear with a Bart's Works SLA frontend. Paul is also the source of lightweight bodywork for SN-95 cars running the now-obligatory 315 front tires. Paul's game is balance and reliability, so we don't expect huge horsepower from him, but we certainly expect him right there for the championship.

Bill Daffron's clean, veteran Fox racer showcases Maximum Motorsports' strut frontend suspension (just like our own open track car) in a sea of Agent 47, Bart's Works, and Griggs SLA frontends. Strong power comes from a series of Mark DeGroff 383-inch Windsors built around stock iron blocks. Bill likes to go fast without over-spending his considerable resources and enjoys twisting the tail of guys running all the trick stuff. Hailing from California, Bill was still learning the Mid-Ohio track after the rain-shortened week, but managed Third in AIX.

Ross Murray is another full-time racer. He makes his living building and servicing race cars, and as multitime regional AI and AIX champion, he has the driving talent to prevail. Ross hasn't mounted his own AIX effort, however, and has occasionally driven Bill Daffron's Maximum Motorsport-equipped Fox Mustang to good effect instead.

Speaking of Bill, this painting contractor drove his own car to Third in the AIX championship race. Even though the car is for sale, we expect to see him in AIX occasionally in 2007. Besides wheeling his hot Mustang, Bill can be found in vintage Winston Cup action and is a sailboat racer along the way.

Guy Cunningham is a full-time driver-for package company DHL-and has shown real talent behind the wheel of Grigg's Racing-prepped AI Mustangs. He will be a threat in AIX if he can get the right equipment under him, but he wasn't scheduled into an AIX ride at press time.

Another West Coast AIX racer to watch is Cory Webber. Cory owns Agent 47 and runs for fun and product development. He's moving his SN-95 racer from AI to AIX this year and is planning on running at Mid-Ohio for the championship in 2007. Fabbed together by Bill Osbourne of Agent 47, the black speedster features an Agent 47 SLA frontend and three-link rear, as well as a 600hp 331-inch small-block. A revvy unit, the naturally aspirated piece goes 7,200 rpm, thanks to prepped AFR heads, a 5.5-inch clutch, and a "tiny flywheel." Cory says it revs like a motorcycle; we can confirm it tears with ear-splitting intensity, so it likely has a ton of compression as well.

Pat Lindsey bought NASA major-domo Ryan Flahety's old AI Fox Mustang and took Second to Ernesto at the Mid-Ohio championship race with it. That was something of a fluke, as Pat could've added weight and ran in AI or removed weight and gone in AIX. He opted for less weight, but after the championship race, he figured he would've done better in AI trim, which is where we expect to find him in 2007. As there is only one spot better than Second, it seems as though Pat is thinking he'll win.

Normally, Ray Mason drives a Grand Am Cup car, but was in AIX because he comprehensively crashed his BMW and had nothing to drive there. His friend Dean Martin at Rehagen Racing had a Grand Am Mustang and figured Ray ought to see what he could do in the AIX championship. Not a Boy Racer, the Rehagen Mustang was built up from a shell. It didn't take much more than putting the required NASA stickers on it to make the AIX championship race; Ray drove it to Fourth Place.

One interesting development is the reengineering Dave Martis has done to his 4.6 Mustang Cobra. Instantly identifiable due to its bright-green paint, the Martis mobile is wonderfully engineered and fabricated. He has added a turbo to the car, placing the snail behind the driver in the backseat. Look for 800 hp or so from this turbo and charge-cooled effort. Paul Brown and Dave have helped each other develop their respective cars to the point of Dave letting Paul lap his turbo-wonder at a test day. If anything, Paul says, Dave's car is faster than his record-setting lap machine, but Dave doesn't have Paul's driving experience-few do.

Another school of thought is to go with plenty of cubic inches and an aluminum block to save weight. That's what two-time AI Ohio regional champion Chris Griswold of Wisconsin has: a big-inch aluminum '86 Fox that does more than 800 hp on the dyno and has proven "sick fast" in a straight line on the track. He also goes through a set of tires each race. If he can hang on to his tires for half an hour, he could stand tall at the checker. Others are exploring this concept as well, and with plenty of Nextel Cup, World Challenge, and other pro-line engines available as affordable used, we could see several more light-and-fast naturally aspirated Mustangs in AIX.

These are just some of the AIX racers to date. Paul Brown is calling for a 25-car AIX field at the 2007 national championship race next September in Mid-Ohio, and he's probably right. We're waiting for the first turbo car to pull on the track. It should be like driving on ice, but when it hooks up on the straight, it ought to look like the road runner leaving the coyote. It'll be fun to watch.

After several years of tuning the rules, NASA honcho John Lindsey-no relation to Patrick Lindsey who took Second in the AIX championship race-says everyone seems happy, and no major rule changes are planned for 2007. What does change is that the fledgling American Iron Vintage class goes away due to a lack of participants, and AI minimum weight has been lowered from 2,800 to 2,700 pounds. The idea is to encourage racers with limited funds to build relatively inexpensive, lower power engines and put them in lightweight cars. Whether anyone can get to 2,700 pounds legally and cost-effectively remains to be seen, but it's an interesting idea.

Ford engineer Robin Burnett is one of the first to debut an S197 American Iron and SCCA American Sedan race car. Assistance from Steeda has helped the two-sanction effort; power is from a carbureted small-block.

American Iron Extreme gets plenty of gee-whiz limelight, but it's good old American Iron that has the winning combination of reasonably technical specifications and close racing from a deep field of competitors that makes it the prime Mustang enthusiast's interest.

Nearly all of the 25 hopefuls had Mustangs. They all lined up in the inaugural AI championship race at Mid-Ohio last September. Rain early in the week limited practice time for many, but the weather was fine for the two heat-race format that led to gridding the AI championship race.

Taking the gold ring was Jason Andrew, followed by Robin Burnett and Dave Royce; all were within three seconds of each other at the checker so the racing was close. Spencer Sharp took Fourth and Matthew Erickson was Fifth.

Jason and Robin enjoyed meaningful home-track advantages, something the early rains amplified as others hurried to dial in their brake bias, alignment, corner weights, damper settings, and so on. Jason had his MaximumMotorsports-equipped Mustang fully dialed in and couldn't be caught.

Robin's carbureted S197 is supported by Steeda and was especially potent on power. The supple chassis setup delivered good drive off the corners, which Robin put to good use.

Dave Royce is Maximum Motorsports' factory driver, and as we've shared Todd Covini's CMC Mustang with him in an enduro, we can attest to his speed. The California-based Maximum team was the first of many suffering from a lack of track time due to the rain. Furthermore, Dave drove Mid-Ohio only once before. The tuned engine-management computer failed the morning of the race, so a stock computer yielding 14 fewer horsepower by Maximum's account had to be installed. Still, Dave was able to pull alongside Robin a couple of times but couldn't complete a clean pass. He finished an honorable Third.

In 2007, these drivers, except Dave, who may be out of a drive as Maximum takes a year off, are the likely candidates for AI glory. You'll also want to keep an eye on Spencer Sharp, likewise Beau Dunnivant has also proven quick, and the Texas region in general has shown a tendency to incubate AI talent. Better yet, build your own AI car and see the action from the best seat in the house.