2NR: I thought that logo was really cool. What was the initial response from the general public?
JK: It was really good. A lot of people were sporting that decal whether they were turbocharged or not. At the time I was cutting out the stickers by hand and it got to be too much of a pain after a while.
2NR: Moving into the turbo industry did you have to familiarize yourself with all the various trims and compressor housing sizes?
JK: As far as the trims and families go...those were pretty much basic. The biggest thing was matching a specific turbo to what was done internally within the engine. For example, turbo sizes are determined by the type of fuel management, the horsepower produced and the type of driving; that's where I think I outshined a lot of these other guys in the turbo industry. I saw a lot of shops or mechanics who weren't aware of the correct turbo applications for certain cars. So they just throw in a turbo for a customer's two-liter displacement engine. Sure it will work but that specific turbo isn't optimal for their specific application, and I saw a lot of that attitude in the industry.
2NR: So what you're saying is a turbo made specifically for one engine will not work as efficiently on another engine?
JK: That's correct. We fine tailored the turbos by downsizing the turbine wheel. If it wasn't available, we had the housing machined to fit that specific wheel, which made it more efficient and produced more power.
2NR: Let's talk about AR ratios and housings for the turbo.
JK: Well if it's used more for the street and it has a 1.8-liter motor built with rods, pistons and an aftermarket fuel management targeting anywhere from 350 to 400 hp, I would recommend a .48 AR housing with a T31-76 trim turbine wheel. Other companies might call this a Stage Three. The benefits of using this setup include maintaining a good exhaust flow with minimal turbo lag. Again, it all depends on the engine setup and how the car is being campaigned. On the compressor side I always like to stick with anywhere from a .50 to a .57 trim, T04E compressor, which gives a broader range.
2NR: What's that setup get you in maximum horsepower before the power levels begin to taper off?
JK: You'll end up choking it with a .48 AR at top end rpm because it tends to produce too much exhaust pressure, but you're still good for about 300 to 340 hp on 91-octane fuel. With a higher-grade fuel you can squeeze out a little over 400 hp to the wheels. If you're building a car for drag, you don't want as much response in the low-end rpm. The logical alternative is to alter the boost characteristics by moving your power range higher up to minimize wheel spin and reduce traction loss. The AR of the turbine housing can shift the power band from lower to higher as the housing sizes increase.
2NR: What are your recommendations when selecting the proper turbo applications for two very different vehicles? For example, one vehicle plans to road race and the other plans to drag race.
JK: Setting up for circuit is a little harder. I would have to find out what type of course the car is campaigning on. For example, the east leg section at Streets of Willow [Palmdale, Calif.] is known as a course that has more twists and turns and is run at lower speeds. The high-speed, 2.5-mile road course at Willow has long straight-aways, which create a whole new situation in turbo selection. It depends greatly on whether or not the stock chassis can handle the power and abuse from track conditions. Given this, the car may handle worse when power is increased as well as you might overextend the limits of the suspension. I would usually go a little smaller in turbo size so the vehicle will have more response when coming out of the turns.
2NR: Can you tell us the main differences between setting up an FWD vehicle compared to an AWD vehicle?