This page shows the results for the horsepower and torque my car is producing, using a program called Street Dyno from by STKR Software, click here to go to their website for more information on the program and how it works. Street Dyno runs on the following systems, Win95/98/NT. The program requires a little tweaking of the parameters to get a clean graph, but I found it very easy to use.
I tried Street Dyno quite a while ago, but had some problems due to using a very old tape recorder (Street Dyno uses the recording of pulses from the ignition), which naturally didn't give such good results, and I got side tracked and never went back to it. Now I wish I had, it works great!! I have to thank Adrian Broughton from the GT-Four mailing list, for using the software and getting some very good results, (the power figures match what the stock output should be), which is what encouraged me to go back at it. Check out Adrian's page by clicking here. Even if Street Dyno didn't match the specified output (which it did), this would be a valuable tuning tool for getting a base reading before doing your mods, and seeing if they really made a difference or not, as well as turning up any strange dips in the power curves.
The skeptic in me never sleeps though, so I thought I'd put the program to the test. I did 4 runs on the same stretch of road. I figure if everything is the same, the four runs should be very close. Well, Street Dyno passed with flying colors, the four runs were within 4 horsepower of each other, and with in 3 foot pounds of torque of each other. That's approximately a 1.5% error margin, and I seriously doubt it's an error, because an engine's output can easily vary that amount.
Below is a screen capture form Street Dyno showing the results of my run from October, 1999 (scroll down to see the latest power figures). As you can see the car made 268 hp at 5,910 rpm, and 284 ft/lbs at 4,510 rpm. With Street Dyno, you can run the mouse along the power curves, and the rpm, hp and torque figures will show in the three black windows below the graph for that particular point along the curve.
Below is the the Street Dyno run I did in August, 2000, showing peak power of 319 hp and a peak torque of 314 ft/lbs. As you can see, the modifications done have definitely paid off. Peak power has increased by 51 hp and peak torque has increased by 30 ft/lbs. The runs have all been done on the same road, and all parameters are the same, except for weight, temperature, barometeric pressure and humidity. Tire diameter has also changed due to the switch from 205/50/15 to 205/50/16 tires. Because of the removal of some parts, the weight was dropped by 20 lbs. In reality the car's weight has dropped by about 35 lbs, but since the driver's weight has to be added, which...ahem...has increased by 15 lbs, it makes it only 20 lbs difference.
Below is a screen capture showing the run made on June 5th 2001, showing peak power now at 356 hp, and peak torque at 335 ft/lbs. What is now noticable is that power is no longer dropping off at high rpms. Unfortunately, I came of the accelerator a little to soon, as power was still on the rise. From the time I first drove the car after installing the HKS 264º camshafts, I could feel a good difference in power, and the extension of the power band. I spent many hours retuning the car to suit the changes made by the camshafts. The result is a healthy gain of 37 hp, and 21 ft/lbs of torque.
Below is a screen capture from the 29th March 2002, showing a peak power of 391 hp, and peak torque at 360 ft/lbs. Quite a bit more tuning has been done since installing the cams. I have also used a new fuel mix, which consists of 20% toluene, and made increases in the amount of water injected, that has allowed more ignition advance. Boost levels have remained the same.
Below you can see a comparison between the first dyno run I did in October 1999, and the most current one almost two and half years later, done on the 29th March 2002. I think this is where my engine modifications end, as I am satisfied with the current power of the car.
page was created by Dennis Heath.
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Please note that I am not a mechanic by trade, and that any information offered on this web page is free and without guarantee. Should you choose to perform any of the procedures listed on this site, you will be doing so of your own free will, and I will not be held responsible or liable for any damages that might occur from using information obtained here.