Brant Campbell, proprietor of the Turbobullet racing website, campaigned his familiar blue 1970 split-bumper Camaro for many years, eventually running well over 200 mph with that car in the West Coast Limited Street wars. Eventually, the old backhalf chassis simply wasn’t doing it for him anymore–it was too aggressively built to be turned into an X275 car, and he had no interest in joining the cubic-dollar burnfest better known as the Radial Vs. The World class–so he made the decision to pick up a solid Fox-body Mustang and outfit it with an all-new, turbocharged LS powerplant built by Steve Morris Engines in Michigan.

The LS has not traditionally been the preferred powerplant for X275-style racers. There are a few who have had success–such as Eric Gustafson–but it’s not the mainstream choice.

“It had to be small-block, and boosted, and I’m a Chevy guy,” says Campbell. “I decided to go with a chassis I thought had more potential to win in X275. I’m hoping to get in the 4.30s with this combo with a lot of testing.”

Campbell had amassed most of the engine parts prior to selecting SME as the engine builder. Although this is not SME’s preference when building engines, the block, heads, intake, dry sump setup, rockers, intake elbow, and throttle body were all purchased from the Turbobullet.com classifieds.

“Every one of the parts is new, but I found them all from people who started builds and didn’t finish,” he says.

With the main foundation pieces in hand, Campbell made a plan to meet with the Michigan-based SME team and get the engine parts machined, tuned up with the Morris touch, and ready for X275 competition.

SME designed and sourced the rotating assembly, while many of the foundation parts were already in Campbell's possession.

Steve Morris Engines typically prefers to develop entire class-legal combinations from scratch to prevent having to accommodate parts the company feels may not be ideal to take advantage of every rulebook possibility.

“While we can work with the parts that a customer provides, we can design and build it better if we start from the ground up,” says SME’s Alex Esnaola. “Purpose-built combinations typically end up making more power more efficiently.”

That said, as you’ll see, Campbell’s engine is no slouch in the performance department.

One of the challenges that any engine builder is faced with when it comes to a customer supplying parts is when those parts may not be as advertised, or there are other fitment issues. For example, Campbell supplied a dry-sump oiling system for this engine, and it wasn’t discovered until it was time for assembly that the pump configuration was designed for a Corvette, and the configuration required for this engine would have been a Camaro fitment, leaving SME to determine the differences and remedy the situation.

Esnaola says it’s not a major issue, but one that could have been prevented if SME had spec’d out all of the parts. Ultimately, they figured it out and corrected it.

Another concern with customer-supplied parts is on full display in the video, where Morris explains that he ordered a crankshaft with the incorrect specifications for the LS Next iron block. Ultimately, rather than force Campbell to wait an additional twelve weeks or more to have a new crankshaft manufactured, SME simply traded Campbell’s iron LS Next block for an aluminum LS Next block they had on the shelf–which the crankshaft fits without issue–to make the deal right.

Despite the initial mistake, “We go the extra mile for our customers where and when we can, to make things right when it is a mistake on our end,” explains Esnaola.

The valvetrain configuration bemefits from SME’s SpinTron testing, and Morris has plans to test more than one camshaft in this engine prior to delivering it.

The LS Next aluminum block is topped off with a set of All Pro LS cylinder heads and intake manifold. SME selected and provided the rotating assembly, camshaft, and other internals to finish off the build. The camshaft is a special highlight of the build, as SME has been hard at work on the SpinTron developing new camshaft profiles and packages for its customer base.

The company has invested in their very own SpinTron; they hired noted SpinTron owner/operator Tom Vigue to bring his talents–and machinery–to Steve Morris Engines.

Vigue boasts decades of testing experience in the NASCAR Cup arena for companies like Hendrick Motorsports and Dale Earnhardt, Inc., and has been applying that knowledge to SME’s engine building program to improve the company’s camshaft and valvetrain selection process.

“We are going to try two camshafts for this engine. This is something that I’m trying on my own so Brant gets the best package out of it. Whichever one is better is the one we’re going to use. This is making the entire package better,” says Steve Morris.

Tom Vigue hard at work on the SpinTron developing new valvetrain configurations.

The engine currently wears a class-legal 85 mm turbocharger from Precision Turbo, but Campbell left himself options by choosing to build the engine to 400 cubic inches–which is larger than some other competitive engines.

The cold side on the dyno is Morris’ own dyno setup, but Campbell fabricates all of his own parts for inside the car.

“It was my choice to build it to 400 cubic inches, just so if I wanted to I could throw a bigger turbo on it and run a different class or just go play,” he explains.

Even with the limited turbocharger on the larger-displacement engine, it still swung the SME dyno needle to 1,934 horsepower. Fueling is supplied by VP Racing Fuels‘ Q16 mix, pushed through Billet Atomizer 245 lb-hr fuel injectors.

The engine makes peak power at 7,100 rpm, and Morris says it’s running out of turbo at that point, but will carry well over 1,800 horsepower up to 8,000 rpm.

“That’s stout no matter how much boost it makes. Very similar combos have been .40s in X275,” says Campbell.

In this particular dyno test, the engine makes nearly 23 psi of boost pressure using the second designed camshaft profile, which was 80 horsepower better than the first profile they designed. The exhaust opening point was changed along with the overlap cycle to realize the performance difference. This camshaft makes more power under the curve, which will help the car to get down the track more quickly.

“The complete and total profile of the camshaft dictates what’s going on here for boost. You could do this motor with slightly different displacement and a different camshaft, and it’s all of a sudden making 30 pounds of boost–but it might not make as much horsepower,” says Morris.

Although the engine wasn’t wearing all of Campbell’s equipment while on the dyno–he uses Haltech’s engine management system, sourced from Joe Oplawski at Hyperaktive Performance Solutions–SME was able to set up a solid engine map for testing using their familiar Holley Dominator EMS, which is used in virtually all of their dyno testing.

Based on Campbell’s history with his front-running split-bumper Camaro, it’s only a matter of time before this Mustang is hurting feelings.

“We’ll give him all of the tuneup information, and he’ll be able to apply that into his Haltech system,” says Morris.

To save costs, and hone his skills, Campbell does nearly all of his own fabrication.

“I build all of my turbo plumbing myself, hotside and cold side. I use a billet merge into the single turbo from Street Carr Fabrication, and the intercooler is an air-to-water from Shearer Fabrications.”

Campbell, who has the car ready and waiting for engine assembly, has plans to run it this season.

“The goal is to have a testing session before the Turbobullet Rebellion race in Denton the first week of September,” he says.

It looks like he has his work cut out for him in X275.