By Chuck Johnson
Photography by Joe Lu and Adam Bendig
The 2014 season has been a tough one for land speed racers in general, with high winds cancelling events at El Mirage and thunderstorms flooding the Bonneville Salt Flats. On the home front, Team MotoIQ has had its own series of struggles to overcome with Murphy’s Law wreaking havoc every step of the way. Nevertheless, we managed to overcome the odds and set a new H/PS land speed record at Bonneville. Recounted through data logs, videos, photos and of course text, here’s our World of Speed story.
Upon arriving at Bonneville, we were greeted by the remnants of Mother Nature’s devastation of Speed Week. The first mile of the salt flats was covered with vast sections of standing water over a foot deep. With standing water at the entrance, we knew that the course conditions would be pretty bad.
The one good thing that came from the cancellation of Speed Week was that it gave my elbow the extra time that it needed to heal. In other words, I was back in the driver’s seat again. Sorry Annie Sam, next time.
During Speed Week 2013, we had secured a new H/PS class record of 178.984 MPH. However, after the fact it would be reduced to 173.329 MPH. Without getting into too much detail, 173.329 MPH was the average speed of Project 240SX LSR between the two and three mile markers on both runs. According to the SCTA rulebook, a record less than 175 MPH must run against on a three mile course. We had done our 178.984 pass in five miles.
What this meant for us, was that we either had a mere three miles to reach 200 MPH or we had to first bump the record over 175 MPH so we could go to the longer, 5 mile course. After much deliberation amongst the team, we decided to try to push hard and go for the 200 MPH mark during the first run.
There’s no doubt that with over 600 horsepower at the wheels, our 5523 Motorsports built SR15VET 20V was producing enough power to surpass the 200 MPH mark. Getting it done in three miles wasn’t completely unreasonable either, even on the salt.
Upon taking off from the starting line though, any thought of laying down a 200 MPH pass was gone. Up until this point, I had only ever had one dodgy moment driving Project 240SX LSR when she suddenly veered left at around 170 MPH during a pass at Speed Week 2013. This time though, I found myself fighting to keep Project 240SX LSR pointed straight and on course every inch of the way.
Upon passing the two mile marker, I knew that I was incredibly behind pace. At this rate, I was in danger of not even surpassing our previous record, let alone pushing it above the 175 MPH we needed to get on the long course. As I pushed harder, Project 240SX LSR continued to oversteer wildly, with the rear end sliding out to the right sending the car shooting left across course. It was a careful balance of applying enough power to continue accelerating while not spinning the car. We managed a 177.492 MPH pass and qualified for the record.
A couple weeks earlier, we had tested at El Mirage. She was definitely faster than ever and with the help of Steve Mitchell from M-Works aligning and corner weighting the car, she was also notably more stable. Something was different, something had definitely changed.
With highly active LSDs or welded/spool type rear ends like we run, a difference in rear tire pressure can cause a car to over steer. While the rest of the team packed up the car and prepped it to be towed to impound, Sean Rossi did a quick check on the tire pressures which revealed a leaking valve stem on the right rear wheel. With the culprit seemingly identified, we removed the tire in impound and had the valve stem assembly repaired that evening.
Later that night, we reviewed the data logs from the AEM Infinity EMS over a few beers in the Rainbow Casino’s lounge area. Some of the locals found it amusing that a group of guys were huddled together in a bar staring at a laptop, ignoring the live band and all the dancing ladies. Eventually, one of the locals came over and asked us if we were watching porno. After a brief exchange and a few laughs, we found out that he was Mike Crawford, Mayor of Wendover. We got a kick out of that… Later in the week, the Mayor’s huge pet parrot would attempt to assault Sean during a bathroom break. That’s a story for another day though.
In reviewing the data logs, we plotted throttle position, boost pressure, and wheel speed along with gear and RPM. The data logs from the AEM Infinity EMS confirmed that I was only able to use a fraction of the power on hand and essentially, I was pedalling the car up to speed at partial throttle using only a third of the available boost pressure. Indeed, I was never able to drive the car flat out as it would snap oversteer the second I got overly ambitious with the throttle.
Although 5233 Motorsports had already programmed in gear dependent boost control ahead of time, we decided that some changes were still needed to make the car more manageable to drive. The ease of implementing powerful changes is where the power of the Infinity EMS really begins to shine.
To make Project 240SX LSR a bit more manageable to drive, Nick pulled boost from 2nd, 3rd and 4th and 5th gear. The reduction of boost would still leave us more than enough power to cross the 200 MPH barrier.
In addition, we decided to soften up the rev limiter as the lack of traction would cause the engine RPMs to shoot up quickly and too abrupt of a rev limiter and cut in power could cause the car to become unstable. Originally, 5523 Motorsports had set up just a basic fuel cut at 9,000 RPM. To soften the rev limiter, a spark cut was introduced at 8,800 RPM along with an ignition retard of 10 degrees beginning at 8,600 RPM.
With the changes to our tune completed, we called it a day knowing that we had to be back on the salt and at impound before sunrise the next morning.
The next morning, Sean re-installed the repaired wheels while Nick uploaded the new tune. It’s pretty impressive to see how easy it is to make changes with the AEM Infinity EMS.
With the changes uploaded, we headed off to starting line to back up our qualifying run and set a new land speed record.
On our second run, we’d lay down a whopping 190 MPH pass, setting a new H/PS land speed record with a two pass average of 184 MPH.
Looking at the time slip above, there’s no arguing that the changes to the Infinity EMS gear dependent boost control system resulted in a more manageable car under acceleration. Quantifiable improvements were seen with an increase in speed through each of the mile markers. The top measured speed was 18 MPH faster than the previous run. Who’d have ever thought that cutting boost would have resulted in a faster run?
Although there was some improvement in stability, the car was still acting squirrelly under acceleration, which suggested we hadn’t yet addressed the root cause. While our record was being certified in impound, we decided to verify the front and rear toe. We found that the rear was approximately an 1/8” toe out. Running a car with the rear toed out is probably one good way to crash a racecar.
Standing behind the car, Nick and I both could clearly see that the right rear wheel was visably toed out. Taking a bit of a gamble, we decided to make only adjustments to the right side to bring the toe back to zero. The behavior of the car had changed since we alignmened the car and shook it down at El Mirage. At this point, we’re still not sure what caused the change in rear toe.
With all record runs being conducted first thing in the morning, we were able to get back in line again afterwards but this time for the longer, 5 mile course. With the toe problem corrected and two additional miles to get up to speed, we were pretty confident that we’d break the 200 MPH mark with this next pass. We all know that Project 240SX earned the record of 184 MPH, but did it actually hit 200 MPH or did we just spin trying? Find out next time on the Road to World of Speed: Part 2!