'One Lap' NSX

Video of the 3.3ltr 600+RWHP Setup!

Building the Beast

Engine

Originally to be a Grand-Am Cup 3.2 liter, is now punched out to 3.3 with my deck pins for strength. I then had the cylinders re-plated. I developed 10:1 custom pistons with Ross, they have .100 extra valve clearance built in and a different dome design then most NSX pistons. I also use double spiral pin locks (4) per piston. The rings are standard file fit with a few more thousandths for the boost and nitrous. The pistons have about .006” clearance. The block was line bored and honed for fitment of my billet main caps with ARP studs to .0025” clearance. The rods were re-sized with ARP 2000 wave bolts for .002” clearance, and bushed for floating pins. HV oil pump with spring shims for more pressure. The oil pan is baffled with (4) hinged one way doors. I cap and re-rout some of the water for my oil cooling. (Water to oil cooler) Added my adapter to route the main oil lines to the sump and cooler, it also has a separate feed for the supercharger, and relocates the filter. The Head Gaskets are steel shimmed like the late model 3.2’s, but I have them made .010 thicker to accommodate the crank relocation from Line honing. Everything was cc’d to ensure the target compression. I header wrap the water transfer tube under the intake manifold. I drill and tap the OE oil pressure sensor for an additional aftermarket sensor, I do the same for the water temperature.  I hollow out the OE thermostat for better flow, while retaining the o-ring design. The heads have wonderful springs from RTR ($1800), titanium retainers, titanium spring cups, machined keepers and the largest high temp stainless steel valves I could fit without hitting them selves.

The valves are lightened and relieved for flow. The bowls have flow work, and most important the combustion chambers are reworked and relieved to the 3.3 bore for better flow.

The intake manifold has the variable runners removed, along with the dual plane divider milled out and blended smooth. Many of original emission holes are welded and blended. The throttle body is a Science of Speed large bore. The injectors are RC. The headers are Comptech, and the Exhaust is made by us, with bank to bank scavenging. The supercharger has a 4” intake and a 3” exit with a 14 PSI pulley. (I’m going to stay tight lipped about the SC until about a month after the One Lap) The after cooler is a 30” x 12” x 3” low pressure drop air to air. I like Water to air, but didn’t think I had the time before this event. I insulated the 3” boost piping, and use a K&N style filter routed to a Cantrell side scoop. The After cooler is fed by two 10” fans when not rammed with the SOS hatch scoop. The cooler is also fed by (2) spray rings of cryo. I’m not yet sure how I will activate the cryo… either throttle position, rpm, or boost pressure. This and the nitrous will be controlled by the AEM engine management. The benefit of controlling the nitrous this way is that instead of just activating at WOT it can be programmed to turn off if you hit the rev limiter. I may also use the AEM for launch control at the drag event. The AEM is supported with an MSD DIS-4 for better coil strength. Depending on time, I may test the AEM coil enhancement, and or different coils. The Nitrous is a Pro Fogger set up that is easily capable of adding 500 more horsepower, but I think were going to limit our selves to 200 or less. The nitrous is fed by it’s own fuel cell, pump, regulator and filter. My calculations were too close to the limit for the existing fuel system feeding the engine. This will also allow me to run race gas in the Nitrous cell. I didn’t want to afford race gas for engine and the 4000 miles. This system will also let me perfectly tune a rising fuel pressure rate based on the boost pressure.

Brakes

Above, I covered the engine, but I didn’t say that we added mufflers. Driving on streets was a concern along with the Beaverun 95 db rule. I’m not sure how well there going to work, they are (2) stainless steel import mufflers… similar to the ones you see sticking out the back of Integra’s. I also replaced my 150 lb steel gas tank under tray with one made from laminated honeycomb (I think it’s weightless and actually helps lift the car a little) The tires are 235/40/17 and 295/35/18 Michelin Pilot Sport PS2… I hope their going to fit! The Brakes in the rear are larger diameter rotors with OE calipers and offset brackets. The fronts are 4-piston Alcon calipers with Brembo 12.9 rotors. Were also trying to get the ABS working again. In addition I added twin bias valves for the rear calipers. Twin, because the NSX has a four channel system… meaning two brake lines running to the rear. Fortunately they run right past the driver. So when I’m board on the track, I can tinker with the front to rear adjustment.

Brake pads have not yet been determined… 

Both the Alcon and the Brembo calipers use the same shape pad with a 20mm thickness.

Speed Factor

We added a second seat and harness so two of us can get from one event to the other. The seat pulls out quickly so we can replace it with a twin nitrous bottle fixture during the events. One of the bottles is for cryo spraying the after cooler. It feeds two odd shaped hallows that spray directly into the flow of air going through the heat exchanger. This is not normally practical for road racing, but in this event we only take two laps at one time, giving us plenty of time to swap empty bottles. The nitrous is made up of (4) Pro Fogger nozzles ported in the intake just past the throttle body. I have a manifold with direct port for each cylinder, but that wont fit in the supercharged and after cooled engine. Technically I would only need one nozzle for 200 hp, but I decided to use two to better distribute the spray pattern, and two will be non functional for this application. I also included a bottle warmer in case it’s still cold in the East. Nitrous would also be impractical for road racing, but this short format will work fine. Not to mention the drag race event. I have been using Nitrous at track events for years now… it’s a not so well known secret weapon. High hp cars can be a handful on the track unless you’re a Trans-Am car with enormous slicks, light weight, and good down force. At local SPO events, even our Cup car can equal the TA handling, but in the straights their gone. The NOS I have in my wife’s car (More then most applications) literally drops an average of 4 seconds off the lap time. This takes the car to a totally different category, and since it only comes on in the straights, it doesn’t affect handling or increase the mistake factor. Of course you can only do 4 laps without refilling.

Aero

Our front under tray will be replaced with a similar part made from the honeycomb material, only it will incorporate about 6” of splitter off the front and sides of the nose. If I get the time I will also incorporate winglets and maybe some sort of scoop in the front. I want all the down force I can get. Because I no longer have the RTR front nose, but I have borrowed back the RTR rear trunk lid and wing… that thing gives enough down force to compress water. Horsepower is not an issue. The rear hatch is replaced with an SOS lexan replacement and a scoop, the hood is an SOS carbon fiber vented. I may also put on functional side skirts depending on the ride height dictated by the tire size.