"We then figured out how to use an MSD rpm-activated switch with a lock on it, and also on the shifter, with another rpm-activated switch. The shifter on the Powerglide and the shifter on the overdrive are not connected-the rpm switch on the shifter turns the overdrive on, and the one on the MSD turns it off. Basically, I don't have to do anything. If there's some human involvement, it isn't going to be consistent. In Super Comp, consistency is the key to winning. The reason why the lock is so important is that on the top of the track, I want the overdrive to stay engaged to where if something happens, I don't want to over-rev the motor.
"Then we wanted even more simplicity, so we stopped using the rpm switches and changed over to timers to activate the overdrive. We still had the switch on the air shifter to deactivate the overdrive on the one-two shift. We also used a second timer to engage the overdrive on the top end. It gave us more consistency. After a few runs on a test and tune day, we could easily move any of the shift points before race day. We did pretty well. We actually won a Wally Award with it in Super Eliminator at the National Open in Division 7.
"I'm making right around 1,900 hp, and this Gear Vendors unit has never come apart, or been checked out. It's still together. I couldn't even guess how many passes I put on it-it's got a minimum of at least 400 passes. It's been in at least three different dragsters since 1997, and behind everything from a carbed big-block Chevy, to a blown Keith Black Hemi. Rick Johnson at Gear Vendors keeps wanting to take it apart and inspect it, but I don't see any reason to. Those guys have just been above and beyond for me."