Jerry Pearson’s ‘91 Miata

You probably weren’t expecting to see a Mazda Miata in Garage Hot Rods.

Yeah, me neither.

But does it make sense to you when you hear that Jerry Pearson’s incredible Miata has a 400 horsepower fuel injected Ford small block, full race suspension, and is, in Jerry’s words “barely street legal”?

Yeah, me too.

I talked with Jerry during this year’s Hot Rod Power Tour. His Miata is gorgeous, so that certainly attracted my attention, but when I saw that V8 under the hood… Wow. I had to find out more.

And what I found out is that this isn’t just a V8 swap. Jerry has put together a well thought out and perfectly executed vision of his hot rod.

“I’ve built cars before,” he told me, “but I was always worried about resale. I wanted to build one more for me. I wanted to do it purpose-built for autocross and road course racing, so I planned everything out before I started. Anything it has to have to be street legal it has, and it has nothing extra.”

Jerry obtained the NA style (first generation) Miata in 2009. It was delivered to his house the day before Christmas. Jerry drove it around the block, put it in the garage, and one week later he had it down to a bare chassis.

“I wanted something more unique,” he said, “and I knew I wanted to do a Miata. I knew these existed, but they don’t exist with this kind of flair. This is really truly a track car, it just happens to be street legal and it happens to be pretty.”

Jerry planned out the entire build. He figured out what he wanted – a car specifically built for autocross and road course racing, with a 5 liter Ford small block, racing suspension, racing wheels, improved aerodynamics, and strict weight reduction.

He did all the research to find the best parts to buy for what he wanted to do. And Jerry gives lots of credit to his wife Mary for her support throughout the build. She ​understood Jerry wanted the Miata to be as good as it can possibly be.

“She knew what I was going to do with it,” Jerry told me, “and said ‘If you have to spend a little bit more money to make sure you never have to walk home, do it.’ And it’s never stranded me.”

The complete build took three and a half years.

Jerry’s first step was to apply LizardSkin noise and heat insulation. “I knew I didn’t want to bake inside the car,” he said. Jerry described LizardSkin as “peanut-butter-ish – but a little bit more runny than peanut butter.” He told me it comes in a 5 gallon bucket and you spray it on like paint. Jerry applied it to the entire passenger compartment, and inside the trunk since the mufflers are under there and he didn’t want their heat radiating into the car.

Next up was the small block Ford. He bought the short block, but did the rest of the engine work himself. It’s based on a 5.0 liter block that’s been bored out 0.030” so it’s now displacing 306 cubic inches. The Edelbrock heads and air gap manifold get fed by FiTech fuel injection. A COMP Cams Thumpr cam works though roller rocker arms.

Jerry’s got an MSD electronic ignition and a small case Ford alternator that he had to move to the other side of the engine to get it to fit. The small block’s radiator and headers are from Monster Miata in California.

Additional engine cooling is provided by the fresh air intake at the turn signal lens under the headlights. Fresh air runs over the headers, and out the louvers on the hood for additional cooling. “The radiator gets the heat out of the engine,” Jerry explained, “but you also want to get the heat out from under the hood.”

The final product is pretty stout. The Ford is putting out 400 horsepower and 400 ft-lbs of torque at the crank.

I asked Jerry how hard it was to fit the Ford V8 into a Miata. I was surprised when he said, “It was pretty easy. You have to do about an hour of cutting, grinding, and welding. At the spot where the frame rail curls around, and goes into the firewall, you just notch that out square and it fits right in.”

The swap uses the stock Mazda front K-member, to which Jerry added a stanchion made out of flat plate. The front motor mounts are out of – are you ready for this? – a 1964 Dodge van. Say what? “You gotta get what works,” Jerry told me. The transmission crossmember also came from Monster Miata and Jerry fabricated the rest of what he needed himself.

The final performance aspect of the build was the suspension. With Jerry’s emphasis on autocross and road racing, a lot of thought, research, and effort went into it.

Want to know how serious Jerry is about turning corners? Check out the springs on his Miata. From the factory, the stock front springs are 168 pounds. Jerry’s replaced those with 700 (!) pound springs. Stock Mazda rear springs are 98 pounds. Jerry’s are 375. They work with tubular control arms from V8 Roadsters, top and bottom, at all four corners. The V8 Roadster arms have better geometry and provide more camber adjustment.

He’s added a 25 mm front sway bar from a 1993 BMW 325i. He told me it’s the same width as the Mazda bar, but with a 5/8″ shorter stroke and a step in it that goes around the vibration damper of the Ford V8 (shown above in the photo on the right). When I asked him how in the heck he found that out he said, “The Internet works wonders.”

For some added stiffness, he installed a brace under the front fenders that ties the shock towers to the door hinge posts. And the Miata has a fully functional roll bar with a cross bar that ties together the top of the rear door post/seat belt anchor.

Miatas come with an independent rear suspension and Jerry’s still does, but it ain’t stock. His has an 8.8″ center section from a Grand Marquis. Why a Grand Marquis? “The Marquis case is aluminum,” Jerry told me. “A Thunderbird case is cast iron. It saves 50 pounds.”

The rear axles and CV joints are out of a Porsche 911. Jerry likes them because they’re sturdy and they can be rebuilt. The Mazda hubs were resplined for the 911 axles. That allows everything to bolt together and keeps the Mazda bolt pattern on all four wheels.

An example of the level of detail Jerry put into the Miata that really stood out to me was the BILSTEIN coil-over shocks. Jerry worked with Fat Cat Motorsports to set them up specifically (and I do mean specifically) for his car.

“BILSTEIN shocks are rebuildable,” Jerry told me. “Fat Cat takes all your information – how you’re ​going to drive it, how much the car weighs, how much ​​you weigh – and then he re-valves the shocks to serve your specific purpose. At rest, the driver’s side of the car is 3/8″ higher. With me in the car it’s completely balanced in all four corners.”

The four wheel disc brakes are from Mazda’s appropriately named “Big Brake” system​. The 2002 11” rotors use​ Hawk brake pads. ​

Jerry’s using 15 x 9 racing wheels from 949 Racing. Those wheels weigh just 11 pounds each. If that’s not enough, the wheels come with two valve stems for running nitrogen in the tires. I asked Jerry what the advantage was to doing that. “There’s no moisture in nitrogen,” he explained, “the advantage is less rolling weight.”

He’s running 245/40/15 Maxxis tires that give him a full 10″ of rubber on the road. Jerry said that’s about the largest tire you can fit into a Miata without doing major work. Just to be sure, all of the fenders have a line-to-line roll on the inner lip to make sure he doesn’t have to worry about cutting a tire.

Jerry designed and built the front and rear air splitters out of ABS plastic. And the detailed approach he took with the entire car is reflected in them as well. Jerry mounted the front splitter to the car with nylon bolts so if he ever hits anything, the bolts will shear off instead of breaking anything on the car.

The Miata that was delivered to Jerry was fully optioned and weighed 2750 pounds. Knowing that fewer pounds would help him get around those road courses quicker, Jerry made weight reduction an integral part of his build.

I was amazed at the level of detail he got into for taking some pounds out of the car. Mazda puts five different wiring harnesses in Miatas at the factory to handle every possible option the cars can have. Once Jerry had his car built, he removed any wiring he didn’t need from every single one of those harnesses and saved 22 pounds.

He also removed the stock pop-up headlights and replaced them with fixed lights. Taking out the old light’s door, motor, linkage, and wiring saved 25 pounds. Jerry made a mold and created his own shorty console. That saved 5 pounds. He shortened the emergency brake handle to save more weight (and to keep it from hitting his leg).

So now a car that used to weigh 2750 pounds weighs just 2200 pounds. Miatas come from the factory with 50/50 weight distribution. Jerry’s is at 50.4 front / 49.6 rear.

With 400 horses under the hood, it was probably an understatement when Jerry told me “It’s peppy.” His license plate – NSTY QCK – is probably a more accurate description.

I was surprised to hear Jerry had not done any autocross or road racing before building the Miata. But that decision, like every other, had sound reasoning behind it. “I knew I wanted to do autocross,” he said, “and one reason was to learn how to drive the car. This is not like driving a regular Miata, or any regular car. I develop the skills on track to hopefully save my life if someone pulls out in front of me or stops too early. I will know what the car will do and how to make the car do it.”

I don’t know if you’ll see more Miatas in Garage Hot Rods, but if so, do you think they’ll be as well thought out, as well built, and as good looking as Jerry’s?

Yeah, me neither.

Photos by GHR and courtesy of Jerry Pearson
Click here to see more photos of Jerry’s Miata