ZR-1 ZR-1 ZR-1 ZR-1 ZR-1 ZR-1 ZR-1 Haibeck Automotive Technology
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Drag Racing the ZR-1
If driven well these are typical ET’s with street tires.
Stock 375 hp. 13.1@110 mph
Stock 405 hp. 12.9@112 mph
510 hp. 12.1@120 mph
650 hp. 10.9@130 mph
It takes experience to achieve those numbers. If you have not driven on a drag strip for a long time, deduct about .5 second from the example times.
The start is very important. Generally, wheel spin should occur for one half to one car length. A good beginning point is to use 2000 rpm for a starting speed. Don’t pop the clutch, let it out over about one half second so that the car gets a good push from the tires before they break loose and spin. If in doubt, less wheel spin is better than more. Watch the 60’ time. If you don’t get a perfect start, a bogging start will have a better 60’ time than a spinning start. Again, use 60’times as a guide, not how the start feels.
With drag radials, start with 2500 rpm in the above prcedure.
The temperature of the tires is important, especially when the ambient temperature is less than 70 degrees. A two second burnout is good, a four seconds of heating is better. Back into the water box area. Hold the car with the front brakes.
The 60' time has a big effect on ET. Generally for the ZR-1, every tenth of a second relative to a 2.00 second 60' time is a gain or a loss. With a 2.00 60' foot time the car should be able to run the ET’s listed. For example for a 2.5 second 60 foot time add .5 second to the ET. 12.9 + .5 = 13.4. If you use drag radials and get a 1.8 '60 foot time, 12.9 - .2 = 12.7 ET.
Shift at 6800 rpm for stock engines. 7000 rpm for ported engines.
Engine heat is a huge performance damper. The engine will make best power at about 175 degrees coolant temperature. 175 degrees is at about 40% of the scale on the temperature gauge. Oil temperature should be over 140 degrees for lubrication and to reduce oil pump drag. You will never run a great time on a 90 degree day. The best conditions for trying to set new personal record are with ambient temperature between 45 and 70 degrees and low humidity.
The air filter can cause variations in performance. I recommend either installing a new AC filter before going to the track, or remove the air filter at the track to eliminate the possibility of a power loss due to the condition of the filter.
Set the shock absorbers to Tour for best weight transfer to the rear of the car.
Try to run with one half tank of fuel. Excess fuel weight slows the car. The power to weight ratio of a 400 hp ZR-1 is about nine pounds per hp. If you are carrying five gallons of excess fuel it’s like losing about five hp.