Tommy's Big Single 93 Rx7

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Home Contacts Links Tommy's Big Single 93 Rx7 Mike's Turbo Convertible Rx7	Tommy's car started as a simple stock rebuild. However, after his motor went off to the builder, the project somehow morphed into a big single project. The builder, Arizona Rotary Rockets (AZRR) is well known for building high horse power rotary motors for street and race applications. I think that Glen at AZRR had a part in persuading Tommy to build his car into the fire breathing monster that it is today.
	As mentioned already, Tommy's motor was built by AZRR of Tempe, AZ. Glen and Tom at AZRR did a fantastic job. Not only did they build and port the short block, but they sourced or fabricated all of the supporting hardware. The resulting configuration is known as AZRR's "Big Kahuna" turbo kit.
	The transmission was rebuilt too, so the tranny and engine were pulled and installed as a unit. This is really no more difficult than pulling the engine by itself. In fact, with the pull style clutch that the FD uses, it is probably a bit easier.
	The use of a larger turbo meant that some of the car's hoses had to be rerouted. The first hose to interfere was one of the heater hoses (right). I straightened the factory hard line, welded up a new bracket for it, and then bolted it in place. It is now mounted about 3 inches lower. Greddy also supplies a new power steering fluid cooler (left). All of the mounting hardware is included, but the hose that attaches to the driver's side of the cooler needs to be shortened, and the hose on the passenger side of the cooler needs to be replaced with a longer one.
	Tommy's performance goal necessitated the use of a larger intercooler. AZRR supplied a Greddy intercooler kit for the FD. The kit is essentially a bolt-in, but it still required that the bumper and some sheet metal be cut. Also, the Greddy kit was intended for use with the stock twin turbos, so some modifications to the plumbing were necessary. The kit also requires that the radiator (left) be mounted in a more upright position so that the intercooler plumbing may pass over and around. This means that some of the car's factory hardware had to be modified. More on this later.
Boost controller hard lines mounted to the passenger side fender well	To the right and left are some shots of the under-hood portion of the boost controller waste gate and associated vacuum lines. The flexible portions of the vacuum lines need to be made of high-temp silicone to withstand the very high under-hood temperatures associated with a turbo car. The close proximity of these lines to the turbo further necessitates the use of silicone. The fact that blue silicone lines look cool is just icing on the cake. I also made some hard lines to actuate the waste gate. I did this in lieu of using three foot long flexible rubber or silicone lines. This almost completely eliminates any chance of the lines wearing out due to chafing. The solenoid for the boost controller is mounted reasonably far away from the hot side of the turbo and down pipe.	Boost controller solenoid Here is a shot of the vacuum lines at the waste gate
	The boost can be varied by the driver from the inside of the car (right). I made the center console bezel for the boost controller's console from a storage bin and some scrap black plastic that I had lying around. I used black touch-up to cover the yellow adhesive around the edges of the bezel after this picture was taken. I also drilled a small hole through the transmission tunnel (above, left) under the center console and then ran a section of 1/4 inch steel vacuum line through it. The boost controller console takes manifold pressure readings from this vacuum line. The other end of the hard line (below, left) makes its way up to the top of the fire wall where a rubber vacuum line connects it to the intake manifold.
	Engine management is handled via Apexi's Power FC plug and play computer (right). The commander for the computer (left) can be used to display coolant temperature, injector duty cycle and a host of other critical engine conditions.
	After the radiator was repositioned, the relay box (left) did not fit. To make room for it, I cut a notch from the radiator core support. The relay box also needed to be positioned slightly higher to allow the lid to open. To facilitate this I made a simple bracket to be slid into the passenger side of the box. I also cut the upper portion of the plastic mount off of the driver's side of the box and then drilled a hole through it and bolted a new bracket in place. The repositioned radiator also made the wiring for the radiator fans (right) too short. To solve this problem, I cut the wires in the middle added about eight inches.
	The radiator hoses needed to be shortened, and Greddy supplied a great solution. Their solution included a pair of steel hose splices and a hand full of clamps. The stock hoses (or a cheaper set) can be cut and the remaining pieces attached at both ends of these splices. Viola! new radiator hoses. For those of you who might consider doing this your self, the part number for the upper hose (left) is L193. The number for the lower hose (right) is S069.
	The relocated radiator also meant that the stock battery and tray would not fit. I fabbed up a new battery tray that leaves the battery very close to its stock location. The stock battery was also much too large, so I used a Miata battery. I have seen many cars with a similar configuration that use a much smaller battery. However, those batteries are more difficult to find. Also given the same cranking amps, those batteries are more expensive than the Miata battery.
	The alternator and water pump are both under drive pulleys. This is good news for the water pump since this car no longer uses an air pump and without the air pump, the W/P, Alt belt makes very little contact with the stock W/P pulley. The larger pulleys lessen this effect. Even with the larger pulleys though, finding a short enough belt is almost impossible. The closest I could find was a belt that was about one inch too long. To make up the difference, I cut the alternator adjusting bracket in half, welded in another half inch of flat stock and then slotted the bracket far enough to pull the belt tight. The resulting bracket works very well.
	Tommy's car was a touring model, so it only had one oil cooler from the factory. To keep up with the greater demand of the Big Kahuna Turbo Kit, Glen at AZRR sourced a pair of after-market oil coolers (left) plus the necessary stainless lines, an fittings and thermostat (right).
	The last day of work on Tommy's car turned out to be a little longer than one day long. I started the last days work on Friday afternoon, worked through the night, and finished his car as the sun was coming up on Sunday morning. Of course, this only served to make the feeling of accomplishment that much greater. Rolling a finished product out of the garage into the first light of day after a month of work is a fantastic feeling. Carlos, also of Tucson AZ, built the down pipe and mid pipe for the exhaust. He also built fabricated the section of intake with the blow off valve. J-Rat of Tucson AZ completed the tuning of this car. Click Here to view a video of the car motoring away from his garage for the first time.