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http://vtec.net/articles/view-article?article_id=415957
Vtec did a dyno on the new EX coupe.
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Note that the higher of the two runs was performed in 3rd gear. The lower was in 4th gear. Power and torque at the hubs indicate that this engine is producing more like 150-155 hp and 135-138 lbs-ft of torque at the engine. Also note that the power peaks and torque peaks correspond almost perfectly with the advertised peaks of 4300 rpm for torque and 6300 rpm for horsepower.
We also noted that the engine would occasionally knock at low rpms, indicating that it might indeed benefit from higher octane gasoline (all testing was done on whatever Honda delivered it to us with - probably 87 octane). Power was somewhat soft below 2000 rpm. We feel that this was probably due to the new small valve opening mode on the R18 designed for optimal fuel economy. Once you got to full throttle and above 2000 rpm, however, performance was brisk.
We have heard some doubt expressed about these numbers, so we thought we would see how the dyno results stacked up with acceleration testing. Our 0-60 testing returned consistent times in the 8.2-8.5 second range. Average acceleration in 1st gear was 0.47g with a 5000 rpm launch. From 4500 to 7000 rpm (the rpm range we accelerated through with a hard launch in first gear), average torque is about 113.5 lbs-ft at the hubs. From past experience, for wheels and tires of this size, a loss of 5-6 lbs-ft of torque is expected from hub to contact patch.
An average of 107.5 lbs-ft of torque, multiplied by a first gear ratio of 3.143 and a final drive ratio of 4.294 gives us a total torque at the axles of 1485 lbs-ft. The tire size of 205/55/16 gives us a tire radius of 1.04 ft. This means an average thrust of 1440 lbs in 1st gear. Our total weight for the car (2705 lbs) plus driver and equipment (230 lbs) was 2940 lbs. This amounts to an maximum average acceleration in first gear of 1450/2940 = 0.49g. While this is slightly higher than what was recorded, launches were performed with a great deal of wheelspin to keep the engine speed up, accounting for some error.
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Vtec did a dyno on the new EX coupe.
Note that the higher of the two runs was performed in 3rd gear. The lower was in 4th gear. Power and torque at the hubs indicate that this engine is producing more like 150-155 hp and 135-138 lbs-ft of torque at the engine. Also note that the power peaks and torque peaks correspond almost perfectly with the advertised peaks of 4300 rpm for torque and 6300 rpm for horsepower.
We also noted that the engine would occasionally knock at low rpms, indicating that it might indeed benefit from higher octane gasoline (all testing was done on whatever Honda delivered it to us with - probably 87 octane). Power was somewhat soft below 2000 rpm. We feel that this was probably due to the new small valve opening mode on the R18 designed for optimal fuel economy. Once you got to full throttle and above 2000 rpm, however, performance was brisk.
We have heard some doubt expressed about these numbers, so we thought we would see how the dyno results stacked up with acceleration testing. Our 0-60 testing returned consistent times in the 8.2-8.5 second range. Average acceleration in 1st gear was 0.47g with a 5000 rpm launch. From 4500 to 7000 rpm (the rpm range we accelerated through with a hard launch in first gear), average torque is about 113.5 lbs-ft at the hubs. From past experience, for wheels and tires of this size, a loss of 5-6 lbs-ft of torque is expected from hub to contact patch.
An average of 107.5 lbs-ft of torque, multiplied by a first gear ratio of 3.143 and a final drive ratio of 4.294 gives us a total torque at the axles of 1485 lbs-ft. The tire size of 205/55/16 gives us a tire radius of 1.04 ft. This means an average thrust of 1440 lbs in 1st gear. Our total weight for the car (2705 lbs) plus driver and equipment (230 lbs) was 2940 lbs. This amounts to an maximum average acceleration in first gear of 1450/2940 = 0.49g. While this is slightly higher than what was recorded, launches were performed with a great deal of wheelspin to keep the engine speed up, accounting for some error.
mg: that's almost as much HP as an 04Si hatch..
