We've all heard it and we've been saying it. "Drifting is going to be the latest craze!" I often get advertisers asking me, "why?" and I think all can agree with me on my answer. If we follow the footsteps in the dirt bike world, Supercross is based on watching who wins the race. You have to know the drama behind the scenes of Supercross to under stand the battles within. This usually means you follow your favorite rider to fight for a third, fourth or whatever position it may be. It becomes a spectator sport if you follow the drama behind the riders. Now, let's look at freestyle motorcross. It's not about who is leading the race; it's about who is scoring the best with the judges. So the spectator doesn't have to know anything about the riders, but they can cheer them on based on how crazy they are on their dirt bike. Basically, drifting is the same thing when compared to road racing. It's not about who is leading in laps; it's about who is going big. The technique and car set up goes against the entire rulebook in road racing but, you have to admit, it's pretty cool to see guys get slideways in a car! Knowing that the difference between road racing and drifting is judging and driving technique, you can bet your ass that car set up is just as important as driving ability. So on with the build up. Based off of our email responses on the issue, I would say there is a 50/50 toss up on sticking with the KA24DE or swapping out to an SR20DET. Since this series will be a four-part story, we decided to leave the first part to involving an engine swap (my apologies to the 50 percent that wanted to stick with the KA24). This will include swapping out the engine, installing a clutch and programming an A'PEXi Power FC ECU. Our home base for the build-up operation is none other then Signal Auto from Torrance--well, they're really based out of Osaka, Japan, but Signal Auto in Torrance is much closer.
You would think an SR20DET would be a hard component to find, but just a few months ago we found out that our office is 30 minutes away from one of the biggest Japanese engine importers in the State. Libero Engine's LTD is not just an import enthusiast's wet dream, it is in fact J-spec engine reality. It's a place where anyone can go to purchase some of the most popular import right-hand drive front clips. You don't just get an engine and tranny, you get whatever is installed on the front of the car. Its almost like Godzilla took a bit out of the back half of the car and left the front half as if it was an inedible fish head. This left us with a clean engine, transmission, wiring harness, ECU and even the front lights and bumper. Of course, no swap is complete without a few extra bolt-on upgrades, so we turned to Signal's mechanic, Hiroki Kitaoka, to make the final decision on what is and is not a good upgrade on our 240.
To start with, we removed the factory clutch and replaced it with an Exedy unit. The clutch is a complete unit that includes flywheel, release bearing, clutch disc and pressure plate. Labeled the Hyper Single, the unit is a single disc, using a carbon metallic material. Being a six-puck, sprung hug allows the unit to be streetable with minimal amount of pedal pressure. Pressure plate clamping force for the 225 model is rated 1200 kgf.
A'PEXi components include a Power FC ECU, air intake and intercooler. A'PEXi makes an intercooler kit for the J-Spec Nissan Sylvia. According to the gang at Signal Auto, the intercooler kit fits in a US-Spec 240SX, but the battery must be either swapped out with a smaller unit or relocated to the back of the car. The reason is the intercooler pipe comes right from under the battery tray. The GT Spec with end tanks specifically designed for the S-14 was the APEXi core that was used. The S-14 in factory trim uses a side mount intercooler that can still be used on a US spec but since our drift project is planning on upping the horsepower level, we decided to cool the air charge with a larger unit. OK, in reality we know it works much better then stock, but having an aggressive appearance has even more to do with it!
The A'PEXi Power FC is a complete engine management system that plugs directly into the factory SR20DET wiring harness. One of the great things about the Power FC computer is that it removes the factory air flow meter with a speed/density three-bar map sensor. Since the Power FC has a base program already loaded, most of the tuning required is to compensate for octane differences as well as mild bolt on modifications. Since the Power FC unit doesn't use the factory mass air unit, we also incorporated an A'PEXi air intake.
While cooling the air charge was important, cooling the water temp was another factor. The factory radiator is very thin and a drift car requires plenty of cooling, because the engine is on constant high rpm as well as bouncing on the rev-limiter through turns. We doubled the core size by installing a Koyo polished aluminum unit designed to bolt right into the factory mounts. Since the factory engine uses a mechanical fan, we decided to swap out to an FAL electric unit which helps us out in horsepower and cooling. The FAL unit is also a bolt on piece to the Koyo radiator. With the radiator change, came a radiator hose change. We decided to use Blitz units since they are much stronger and allow for an additional water-temperature sensor. They are made of silicone rather than rubber to hold up against extreme pressure.
Since the vehicle is factory turbocharged, we turned to Tanabe Racing Development for a few key components to free up some additional horsepower. To start with, Hiroki installed a Tanabe Super Medalion Racing-Spec exhaust system. The exhaust is a full stainless unit that uses an extremely small wall thickness. Tanabe uses a special process that makes the exhaust much thinner than normal, allowing the exhaust to be very lightweight. The Tanabe downpipe is also made in the same fashion as the exhaust. Because it's three inches in size and stainless, it helps the turbo breathe much easier and protects against rust. Later in the story we will unload an arsenal of Tanabe suspension components.
With this series of our parts complete, it's now time to sit back and watch Signal Auto's Hiroki Kitaoka get dirty on our project while we keep our hands clean to take pictures. How unfortunate for us. In part two we will go over an array of Tanabe suspension drift components and a Kaas limited slip install.