The hauler of Dalton Zehr...
The hauler of Dalton Zehr Racing arrives at New Smryna Speedway in Florida to begin the track testing phase of Project G.R.E.E.N. This was a test of different fuel-delivery systems, different fuels, and even emissions-reducing catalytic converters. What we discover and report may well be the future of stock car racing.
The second phase of testing for Project G.R.E.E.N. has arrived. You'll remember back in the May issue of Circle Track we hauled our GM Performance Parts CT525 down to Mast Motorsports in Nagadoches, Texas, for three solid days of dyno testing. While there, we tested carbureted and fuel-injected configurations of the motor both with and without catalytic converters. We also swapped back and forth between 100-octane race gas and E85. The test results were published in that May issue with a more deeper study on the results conducted in the September issue.
In order to validate our dyno session, we planned on testing the same configurations on the track. The technical report on our findings will be published next month, in the January issue. However, we wanted to show you just how much work went into this test and how we got those results. It's a very interesting story.
Our group of technical experts who participated in the dyno session agreed to come down to Florida and lend their support to an on-track test session at New Smyrna Speedway. As to the car, Marty and Dalton Zehr were kind enough to lend us one of their chassis, the tranny and rearend, and so on, so we could install the engine, dual fuel tanks, and all of the other related hardware and software needed to complete our testing.
The idea is to back up our dyno tests with real on-track laps run at racing speeds, or as close to that as possible. I can tell you that Dalton was as consistent as a driver could possibly be and clicked off laps within several thousandths of each other; more than enough consistency to provide usable data. And, as is always the case, Marty and team member Mark Jones jumped in with all four limbs and worked hard for days on end preparing this car.
The key technical players attending the test were Forrest Jehlik and Danny Bocci, both from Argonne National Laboratories; Dave Kalen, representing Sensors, Inc.; and Horace Mast, owner of Mast Motorsports. Rob Fisher provided support while I worked alongside Marty and his gang at the shop prior to the arrival of our tech staff.
We began our build with the...
We began our build with the engine. Here, Mark installs the Jones Racing Products kit designed especially for the CT525 motor. It includes everything you need from the water pump, to the alternator, to power steering. Next, we installed our clutch pack from Quarter Master. On went the bell housing and tranny and we were ready to install the engine in the chassis.
I can say, honestly, that this "build" was extremely difficult due to the fact that we had to fit the engine with the two induction systems along with all of the test equipment, the wiring harness for the computerized ignition and fuel injection controls, and mount the SEMTECH-DS analyzer into the car. We installed two separate fuel tanks to hold the racing gas and the E85 (a blend of 85 percent ethanol and 15 percent gas), all provided by VP Racing fuels. Our fuel line was drained between the runs with each configuration and the fuel pressure had to be adjusted from carb to fuel-injection, or from around 6-8 psi to 60 psi.
All in all, things got done, the crew all came together well, working to complete the assembly on Monday. We made it to the track on Tuesday morning, July 13, for what was to be a very lucky day. Just one rain delay on Wednesday and we were able to complete our testing on Thursday afternoon. Now the team will run the data, compare results and make a full report. The following is a pictorial report on the construction of this great-looking Camaro-bodied car that might just help shape the future of circle track racing.
We weren't quite sure how...
We weren't quite sure how the engine would fit fore and aft, but once we had it positioned over the chassis engine mount tabs, we made a quick measurement and found that the driveshaft distance matched the length used for the crate motor that had run in this car. The height was adjusted to a 2-degree angle, rear down, so that the oil pan just cleared the ground should the bottom of the car come in contact with the track surface. For our pinion angle, we rotated the pinion up to a 2-degree angle to match the transmission output shaft angle. A slight difference in height between the ends of the driveshaft provided plenty of angle differential at the U-joints. The mounts were tightened and we were now ready to move on to the next phase of installing our Schoenfeld headers.
The header design for this...
The header design for this Pathfinder front stub caused a conflict with the connection of the plug wires and with the individual coils over each cylinder on the CT525. So, we had to fabricate a new mount for the coils up and away from the headers. In addition, we had to have new, longer wires made by Phillips Racing Wires. The new position also provided separation from the heat of the headers. Mark did a fabulous job of fabricating these new mounts. With the headers in place and the plug wiring straightened out, we now had to install the stock wiring harness that would connect all of the systems, sensors, and computers needed for our test. This was not an easy task either and Mark had to cut a large hole in the dash to allow the large plug-ins to be threaded inside of the cockpit. Mast provided a wiring plan and it was simple and to the point. We easily found each plug and wire we would need and made our connections. This process was made simpler by the fact that each plug was different than the others.
Mark carefully welded on the...
Mark carefully welded on the six bungs that were needed to place two thermocouples, two air inlets, and two O2 sensors into the exhaust stream at predetermined locations. We needed to monitor the oxygen content of the exhaust at a point before and after our air injection ports. Air needed to be pumped into the exhaust so that the catalytic converters will have enough oxygen to burn properly and help reduce harmful emissions. In dyno testing, we were able to see a significant reduction of those harmful emissions using racing catalytic converters. We hope that we will see similar results once all of the data has been reviewed. One of the most meaningful results of that dyno testing was to find a very small drop in hp using the cats. So, racers don't have to worry that running cats will hurt their performance. The use of E85 fuel recorded a significant gain in hp and torque and the power curve was improved on the low end when we switched to the FI system on the dyno. A combo of E85 and FI results in more power.