Well after a monumental effort we are 'done' in Southern California - finishing up at Turn Key Engine Supply and heading towards "home". It's been a long three weeks but we are winding it up on a high note (* or so it seems). When David brought the car down to San Marcos our first stop was Best of Show Coachworks where they looked over some touch-ups on the passenger door and scoped out a plan of attack.
From Best of Show David headed down the street to Turn Key Engine Supply where Kory started working on a calibration for the ECM but almost immediately found some issues. First and foremost - there was no mapping for an idle or intermediate circuit; this explained the erratic idle and hard starting when it was warm. This was an easy fix but led to another discovery - the Throttle Position Sensor (TPS) signal has an erratic 'burble' that seemed related to the harness or ECM. Changing the TPS yielded nothing, confirming that the issue was internal to the system; the meant that no matter how close Kory was able to dial in the idle, it wouldn't be stable or predictable. While we pondered that problem Kory did an initial power pull and found our third major issue - under even light load there was a significant voltage loss that was hindering the calibration throughout the power band and was probably responsible for our 148 mph engine cut-out issue that we encountered at the Optima High Noon Shootout at the Nevada Open Road Challenge. That marked the end of our first day on the dyno - it was back to Best of Show to lick our wounds, get started on the door, and install our new Magnum T-56 transmission from Classic Chevy 5-speed.
Work at Best of Show started quickly and in no time the door was in primer and the new transmission was in place. The first issue we found with the transmission swap was the shifter location - we knew that the Magnum relocated the shifter slightly but we got a brand new Hurst shifter that was supposed to position the shifter in a 'standard' position. It didn't... Best of Show quickly began working on some modifications to the shifter and handle and in no time Chris was able to get us back in business. The second issue that we found was the driveshaft - the one we had was too long. While this was expected, what was not was the fact that out old driveshaft could not be modified... we needed a new piece made up. For this we turned to Inland Empire Driveline who built us a new 3 1/2" aluminum shaft the next day. Unfortunately... it was 1" too long. David quickly turned around to LA and waited while the driveshaft was shortened and rebalanced. With the transmission in place and the door cleaned up, Dave and Best of Show focused on addressing the wiring issues that we encountered on the dyno the week before. A couple of days of hard work and we were on our way back to Turn Key for another dyno session.
Tuesday morning David rolled in to Turn Key with high hopes. A new, beefier power wire had been run for the alternator and a ground was added to ensure that it was charging to its full potential. A relay had been added for the ECM power supply and everything seemed to be in order. First look - the TPS irregularity was still there... strike one. That hurt but once again Kory decided to do a power pull while we evaluated our options for the idle tuning. Fourth gear... get on the gas... clutch is slipping... strike two? more like a bean ball... we're toast. We hadn't had any issue with it before and were stumped with the problem now.
An hour earlier we were expecting to wrap the day up and get David home... now we were contemplating our next step and wondering if we were going to able to make the Silver State Classic Challenge. What a demoralizing turn of events...
Back to Best of Show and up onto the lift... where Dick quickly found the problem - the hydraulic throwout bearing was stuck and maintaining pressure on the clutch. We were able to pry it off the clutch and the guys quickly noticed that the clutch pedal/master cylinder was binding and needed a simple adjustment. Thankfully they were able to resolve it quickly and, after a quick test drive, a third dyno session was arranged for Wednesday morning. In the mean time one of the techs at MSD/Painless replied to my question about the TPS... maybe there was a light at the end of the tunnel...
By noon Wednesday Dave and the Camaro were back at Turn Key Engine Supply and to nobodies surprise the TPS tick was still there. After looking at a couple of options Kory's focus turned to the Wideband O2 sensors. Following the techs advice the widebands were disconnected and immediately the TPS issue was resolved. With some quick tuning to clean up the idle it was time for a power pull... success - no clutch issues, no voltage issues, Kory was clear to work on some final tuning. When he was done the car was running like a top and had made 475 HP at the rear wheels with 447 ft.lbs. of torque.
With that David was finally able to pack up the trailer and was on way back home. It had been nearly three weeks but we had made some tremendous progress and by all accounts the car was far better than it had been before... or so we thought...
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