We’re back at it with the Rock Bug, this time going over the entire vehicle without the pressure of a ticking clock. Our goal now is to have the Rock Bug ready for the first W.E. Rock Western US National Rock Crawling competition on April 4th, which will mark the Rock Bug’s ultimate debut. For those that followed along with our Rock Bug King of the Hammers updates, you may recall the Rock Bug was struggling with what we thought were motor and transmission issues.
To quickly recap, the day before the KOH race the team came to the conclusion that the stall speed on the torque converter was set to high and the low end torque of the motor was far from ideal for rock crawling. Although the Rock Bug could arguably run KOH, the risk of damaging the motor just weeks before the Rock Bug’s intended purpose of competing in W.E. Rock, the last minute decision to pull from the event was made. Whether this was the right thing to do is still a hot topic around here, but you have to do the best you can with what you have.
There is no question weeks of countless sleep and the pressure of race day may have gotten the best of the Rock Bug team at KOH and here is why. The Rock Bug was back at our shop this past weekend for a closer inspection of the problems experienced at KOH. It appears these problems were not as they seemed, which can be both good and bad depending on how you look at it. The stall speed on the transmission was not set too high as originally thought, but in fact set far too low at about 1000 RPM. This in turn gave the impression that the low end torque of the motor was far from ideal.
So the solution will be installing the right torque converter with a 2200 RPM stall and re-tuning the Scat V4 for rock crawling. The Rock Bug went back with Tracy on Sunday the 15th for some well deserved seat time. Tracy and his co-pilot for the day, Dave of Powerhouse Motorsports, had a chance to run a full trail with the Rock Bug this past Monday. Both agree the Rock Bug is in great shape for rock crawling and have since ordered the 2200 RPM stall speed torque converter. Once the torque converter is installed, the Scat V4 will be re-tuned for rock crawling and trail tested. Yes, this was indeed a lot of drama all because of a torque converter.
Tracy’s seat time is probably more valuable now then almost anything else we can do, so while the Rock Bug was in our shop this past weekend we took on only the absolute necessities. For W.E. Rock regulation, we had to build a very small & simple front bumper. I have included a few pictures below and do apologize in advance for the low quality photos. The camera is being repaired and all that was on hand was an iPhone.
Still to come for the Rock Bug are changes to make it even lighter for W.E. Rock. Due to time, these changes will not all make it for the first event but are coming. These changes include, but are not limited to, swapping the rear steer axle for a a chromoly Spider 9 full floating axle as well as replacing the fuel cell for a smaller & lighter version. King Shocks is building Tracy some custom air shocks just for rock crawling, which will not only perform better but will also save weight. Once we get all of these changes in place, we will make a point to weigh the Rock Bug which we have been dying to do since KOH.
Lastly, while at KOH we received a few dyno videos, courtesy of Tracy, related to our blog entry The Sultry Sounds of a Scat V4. These were taken around the 21st of February and will be included below.