Mitsubishi Lancer Evolution VIII Buschur Racing - Boost Brothers

"While the car was down I decided to install our off-the-shelf GT35R that uses a cast manifold that we designed and have cast locally," Dave says. "The kit also uses an investment cast Forced Performance turbine housing and TiAL 44mm wastegate. After doing this, the additional lag that the GT35R added made the car not so fun to drive." On the dyno, power was stuck at a mediocre 499 whp. That's when Dave said he knew something was missing. They tested many different cams and, after much research and testing, they found a few sets that performed very well in the EVO's 4G63 and power went up. "We took a few different cam grinds, had them looked at by another reputable cam company and came up with a mixture of the best cams and had our own ground," Dave says. After getting the custom ground cams in the car they ran out of fuel. "At that time we were running a single high-output Walbro in-tank pump. The power was now at 542 whp, I was beyond maxing out the duty cycle on the injectors as the fuel pressure was falling off drastically," Dave says. Despite the lack of fuel, the car was able to run a 9.97 at 142 mph by driving it to and from the track in full street trim on BFGoodrich Drag Radials."

The next problem was the lack of fuel. "After some studying, I found that we could modify the factory fuel pump assembly and build an in-tank double pumper, using two Walbro pumps," Dave says. "In theory this would be enough for just about 1,000 hp, even with running the stock feed and return fuel lines." After they fitted the new double pumper, the duty cycle on the injectors dropped from 100+ percent to only 65 percent. With the fuel problem solved, the car made 590 whp on their dyno.

"Over the winter of 2006 I decided I wanted to see what the car would do with a larger turbine housing on it and I also wanted to try a [Full Race] header," Dave says. He built a custom 02 housing dump tube for the 44mm TiAL gate and down-pipe to finish it off. This combined with a 0.82 A/R turbine housing picked the car up even more. "The car then went up to 642 whp and 530 lb-ft of torque. The powerband runs flat from about 6,000 rpm all the way past 9,000 rpm," Dave says.

Back to the track, running on Toyo Trampio tires, the car laid down a series of nine-second runs. It's best run to date is 9.77 at 148 mph. "The car spins the tires very easily so it has to be babied off the line, best 60-foot is a fairly slow 1.63 and it crosses the finish line in fourth gear ... at 9,650 rpm," Dave says. The engine can easily go to 10,000 rpm and this is where the rev limiter is set.

"This car is a legit street car, not a race car that is paraded as a street car," Dave says. "It is driven to and from the track and I take my kids to school in it." It's loaded with all the door beams, both airbags and the seatbelts. Dave says that's because it was built to be driven. "After 19 years of building nothing but 4G63 engines it is still hard for me to comprehend how 122 cubic inches can put out over 750 flywheel horsepower, run 10,000 rpm, knock out 27 mpg on the highway, idle in traffic all day and still be reliable."

Dave would like to say he's done with the RS, because he doesn't know how he can improve on it much more, but he's already developing some new lightweight chassis components that are going to find their way on the car to lighten it even more. "I am also thinking a set of slicks, just one time, would be nice as the car would easily run some 9.4s at 150 mph with some traction," Dave says.

The shop has a race-only EVO for pure quarter-mile domination and we can understand why Dave doesn't want to endanger his drivetrain - his kids have to get to school.