(This article first appeared in the July 2008 issue of SportsCar magazine)

By Jason Isley

It has been nearly a year since our Project Sentra graced the pages of SportsCar. When we last visited our 2004 Nissan Sentra SE-R Spec V, the car was in the Rally Stock Front Wheel Drive (SF) class and we had aspirations of moving into Rally Prepared Front Wheel Drive (PF). Unfortunately, the conversion from Stock to Prepared trim took much longer than we had planned – but isn’t that the story of any project?

Phase one of our transformation from a dusty Stock car to a Prepared monster was driver safety and comfort. The first item on our list of modifications was to install a proper race seat and harness system. This would also aid in keeping the driver safe in the event of an incident.

For the race seat we decided to raid our storage bin, so we dug out a lightly used Racetech RT4009HR. This seat was rescued from a previous project car that has since gone away, but we liked the seat so much we hung onto it just for an instance like this. The RT4009HR is FIA approved, lightweight and is just about as comfortable as race seats get. We turned to Beta Motorsports for help installing the seat. Beta owner John Coffey combined the existing stainless steel mounts, which were on the seat from our previous installation, with some aluminum plate to create a solid mount for our seat.

While we had the car at Beta Motorsports, we also had Coffey design and install a harness bar so we could correctly utilize a five-point harness. To make the bar as strong a possible, Coffey welded a 1.5-inch steel tube directly to the Sentra’s B-pilar.

As is the case when building any project car, you sometimes jump too far ahead of yourself – and we’re no exception to this rule. After Coffey attached the bar, it occurred to us that we hadn’t double-checked the RallyCross rulebook to see if this modification was legal for the Prepared class. The rules did not clearly address this type of installation, so we contacted Jayson Woodruff, who is a member of the RallyCross Board

“The harness bar is well within the spirit of Prepared,” says Woodruff. “There’s also the Stock allowance of ‘additions of protective equipment,’ and more specifically ‘driver restraints,’ which can certainly be argued.” Whew.

With the legalities of our harness bar taken care of, we attached a five-point restraint system from Impact Racing. These lap belts tighten from the center, allowing for easy belt adjustment while in the race seat – a big bonus for us since this car would see multiple drivers.

The downside to our driver safety upgrades was that ingress and egress was now more difficult – even uncomfortable – due to the lack of range in the factory tilt steering wheel and high side bolsters on the race seat. To solve this issue, we once again turned to the past project car take-offs pile. This trip to the pile revealed a red leather Isotta quick release steering wheel.

While we can’t say for sure why this particular item was ever saved, it solved the current problem and gave us a touch of bling. An added bonus was this wheel has a built-in chronograph and shift light – functional bling. To fit the steering wheel to the Sentra we had to modify a Momo hub adaptor from a Nissan 350Z, as there is presently not a direct fit part for this application.

Freeing the power

Well on our way to a Prepared class car, we knew it was time for more power. We placed a call to AEM for a number of parts. AEM sent both a Short Ram Intake and a complete Cold Air System designed for our Sentra, so we could figure out which would be best for our RallyCross application. Comparing both systems, we were concerned that installing the Cold Air System, which locates the filter element behind the front bumper, would expose the system to a lot of dirt, so our plan was to opt for the Short Ram Intake despite the fact that this system would pick up hotter air.

Once we removed the stock intake system, which includes a large intake chamber behind the front bumper, we discovered it was actually cleaner behind the bumper than in the engine compartment. Consequently, we shifted gears and installed the complete Cold Air System – no more sucking hot air from the engine compartment.

With an increased volume of cooler air coming into the engine, we needed to be able to evacuate it as well. The restrictive stock header was replaced with a DC Sports header. The 4-2-1 header design is ceramic coated and also removes the stock catalytic converter.

The Prepared class rules require a working catalytic converter in the exhaust system, so we took advantage of the allowance to upgrade to a high flow unit. We selected a spun metallic catalytic converter from Magnaflow Performance Exhaust. The metallic core offers a free-flow design that is still EPA compliant, allowing for maximum power. Inside the massive Magnaflow catalog we also found a direct fit cat-back exhaust system for the Sentra. Having used Magnaflow on a number of projects in the past we knew we couldn’t go wrong with these parts.

Good looks and grip

When we started to research the conversion from Stock to Prepared, we spoke with a number of drivers and rally car builders about which parts to upgrade. In almost every case, the answer was: “It’s a waste of time.” We looked at suspension changes, shedding weight, more power; we were told that it all makes very little difference on a RallyCross course. However, the one item that everyone agreed as the most important modification was rally tires.

A call to Falken landed us a set of Azenis RS-01D 215/60-15 tires in the soft compound. According to our sources, this set of tires should transform the car and create an entirely new experience. The downside, however, is that Falken no longer sells these tires, but if you shop around the Internet, you can probably find a set or two floating around.

What self-respecting RallyCross car can show up on a rally tire without wheels to match? Team Dynamics is one of the leaders in rally wheels, as well as being a supporter of the SCCA National RallyCross program (even offering contingency), so it was a no brainier to pick up a set of Team Dynamics wheels.

The Pro Rally 1 is a very rugged design that combines a cooling venturi to direct airflow along with great protection for the brake rotors and calipers. To get the full rally look, we went with a set in white that measured 15×7-inchs. We did have to do a small amount of machining to get the Pro Rally 1 to fit the Sentra – the hubs on the Sentra are a little larger than many cars with a similar bolt pattern, but as solid as these wheels are we don’t think that the small amount of material we removed will be an issue.

The National Challenge

With all of our planned modifications completed, all we needed now was an event with a high caliber of competition, and lucky for us, the RallyCross National Challenge series was making a stop in nearby Lucerne Valley, Calif. This is when thing started to go wrong. Shortly before the event SportsCar Editor Philip Royle, the only person on staff who had any RallyCross experience, suffered a hand injury, relegating him to the role of spectator. This left us heading to the National Challenge with an untested car setup and a rookie driver behind the wheel.

Upon arriving at the event site, the news just got better. We found that we would be the only entry in the RPF class. That would take the pressure off and give us an easy win, but not wanting to take the easy road we opted to move to Rally Modified 2 (M2) – the top level class for any two-wheel-drive car. Now we had 10 drivers to compete with.

Figuring a mid-pack M2 finish would be respectable, Associate Editor Jason Isley took his position behind the wheel and prepared for his RallyCross debut.

After the initial runs, our guess looked to be accurate as we were sitting dead center in the results. Then things started to turn around. With each run, Jason started to make the adjustment from autocrossing on pavement to autocrossing on the dirt. At the end of the day, after 10 runs spread over three different courses, our Project Sentra was in first place in M2 and held the second quickest total time for the event.

Needless to say, we were thrilled with the results. It is pretty clear to us that with some more seat time, some testing and a little elbow grease setting up the car for the surface, our Sentra could be a contender for a RallyCross National Championship. Now it’s just a matter of getting the car to Tennessee.

Sources:
http://www.aempower.com
http://www.betamotorsports.com
http://www.falkentire.com
http://www.impactraceproducts.com
http://www.magnaflow.com
http://www.momousa.com
http://www.nissanusa.com
http://www.racetechseatsna.com
http://www.scca.org
http://www.teamdynamicsracing.com
http://www.tirerack.com