Blackbird Challenger Gearing Up To Defy Expectations Once Again, This Time In NMCA Xtreme Street

10 min read

Blackbird Challenger Gearing Up To Defy Expectations Once Again, This Time In NMCA Xtreme Street

10 min read

“As a kid, I really wanted to be a fighter pilot,” Geoff Turk explains. “But my eyesight went bad – I’m extremely near-sighted. Around that same time, my brother brought home an old Pontiac Tempest that he wanted to turn into a drag car. So I figured that if I wasn’t going to be able to fly planes and go fast in the air, I should probably learn how to go fast on the ground.”

Throughout his career, Turk has been involved in just about every motorsport discipline you can think of, from circle track and rally racing to autocross and endurance road race events.

“But most of my professional driving has been at the drag strip,” he notes. He made his first pass at the ripe age of 13, and began building cars of his own not long after that. “The first was a ’69 Dodge Charger, which I bought to build as a bracket racer before I had my license.”

The 426ci, gen-3 hemi mill in Blackbird turns out an incredulous 1712hp thanks to motivation from a big, Whipple blower.

The Charger would then lead to a string of Mopar race car builds. “I terrorized my boss’s Corvettes with this ’73 Barracuda I had,” he recalls of his days at the General Motors Institute. “And after I finished school at GMI, I immediately went back to racing that car, and I did pretty well with it, then I switched to a ’73 Road Runner that I ran in Stock Eliminator. After that I built a ’68 SS/AH Hemi Barracuda tribute car for the Super Stock class, which was full of bunch of crazy guys pushing 426 Hemis to the outer limits. Parametrically, those things make more power than Formula One engines. It’s crazy.”

Given his penchant for Hemi power, it should come as no surprise that Turk was anxious to get behind the wheel of the 2015 Dodge Challenger Drag Pak. “I was actually supposed to get the first car built, but there was a mix-up about my car being painted flat black,” he says. “It’s the only Challenger Drag Pak ever built that wasn’t painted white, and because they painted it black for me, it got pushed back in the build order – I think it’s the 13th one built or something like that.”

He’d originally intended to run the car in NHRA Super Stock due its competitive-but-relatively-budget-friendly format, but at the 2016 US Nationals he was coaxed into running in the Factory Showdown class. “That’s how I started down the path of the heads up, all-out showdown format,” he says. “But also I had all these people at the US Nationals telling me I’d never be able to compete – they said the car is too big, too heavy, and that the Hemi would be no match for the LSXs and Coyotes. And so, after being told by about a half-dozen people that I couldn’t do it, I had to do it.”

Turk went on to make the first 7-second pass in the Factory Super Cars class, which mirrors the rule set used in Factory Showdown, then later took home the 2018 NMCA championship that same season with the Blackbird Challenger. But despite winning the championship and helping the Mopar factory team and Don Schumacher Racing bring home an NHRA title with Leah Pruett in another Challenger Drag Pak, the Mopar guys unceremoniously cut ties with Turk not long after. “They essentially said, ‘OK, we’re got this figured out now – we don’t need your help anymore.’”

The Ford factory team seized upon the opportunity. “The guys from the Ford program came and asked if I’d be interested in running a Cobra Jet Mustang and helping with development,” he says. “And of course I had a bit of a chip on my shoulder with the Mopar folks, and I wanted to prove that it wasn’t just a fluke, so I switched to a Cobra Jet.” In 2019 the Cobra Jets won 12 of the 19 shootout races, along with both championships – much like the Challengers had the year prior.

But after some significant personal events and taking on a new gig at Holley, Turk found himself turning his attention to the Blackbird Challenger once again, which re-emerged at MoParty 2020 with some newfound potency. “We decided to reconfigure it for Ultra Street/Xtreme Street, which is a class that runs these 275mm radials that have become so popular,” he says. “We also built a new engine for it, and it makes quite a bit more power.”

Xtreme Street allows for up to 440ci, whereas Factory Showdown capped displacement at 360 cubes. “So we built this engine out to 426 cubic inches,” he says. “We also don’t have to use a factory cylinder head in this class, so we’re moving to a Hi-Tek cast Gen III Hemi head. We were also using a 2.9-liter, third generation Whipple supercharger in the Factory Showdown class, and we’re moving up to a Gen V 3.0-liter Whipple blower with the new engine, which is a big upgrade in terms of efficiency. It’s also exactly the same one ran on the Cobra Jets.”

At Holley MoParty 2020 Blackbird emerged with its freshly dyno'd engine. Shown, Geoff lights the hydes on the fresh build.

Free from the Factory Showdown limitations on rocker geometry and camshaft lift, Turk has made upgrades there as well. “Likewise with pistons, rods, and crankshafts – all of that in Factory Showdown is dictated within a narrow rule set. In Xtreme Street and Ultra Street, you can do pretty much whatever you want there. There are limitations – you can’t use billet blocks and billet heads, for instance – but other than that, it’s pretty wide open.”

All in, the new mill makes quite a bit more than the Drag Pak’s original Hemi did. “I posted a dyno curve on my Facebook page that shows it making 1712hp,” he points out. “But it’s got a bit more in it that we didn’t show people.”

Despite the newfound grunt, Turk acknowledges that the Challenger is still an underdog going in this new format. “The goal is to bring the car back out and be competitive, and to be competitive it’s got to run between 4.60s and 4.80s in the eighth mile consistently. The fast guys can go 4.50s sometimes, but they often hurt things getting there. But the difficulty is that if I leave the car uncut, I can’t get the Challenger down anywhere close to the minimum weight. The car was at 3600 pounds, and after the carbon fiber bodywork and all the other weight savings we’ve done, we’ve got it down to about 3400 pounds with me in it. But the class minimum for Xtreme Street with this engine configuration is 3150.”

He’s already got a contingency plan, though. “If we can’t get it done with this car, we’ll probably put together a purpose-built version to run this class. But we’re going to try to get it done with the Blackbird tuned up a bit. For a while I kind of had this fantasy of bringing the Blackbird out and running 4.80s and being okay with being a mid-pack guy. But I’m not going to be okay with being a mid-pack guy.


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