4/30/99:

I think my initial figures are incorrect, especially after looking at the other exhausts articles and comparing the results. When I initially posted the article I used before and after dynos taken on different days. I think the ODBII adaptation caught me, because if you look at the numbers it would appear that I had a peak gain of 7 ft/lbs, average gain of 5.8 ft/lbs across the entire RPM range, 7.8 ft/lbs gain in the 3k to 5k range (driving range). The 7.8 ft/lbs of additional torque is roughly a 4% gain in power in the highly used 3k to 5k RPM range.

What's interesting is if you compare Alan and my "after" dynos you see that they are practically identical. How can the Remus give me a 4% gain and the Supersprint give Alan a 2% gain, but we end up at the same numbers? I think the answer is that my original "before" dyno is questionable. What I did to try and "fix" this error was take the two different "before" dynos and combine them by using the high points from each graph. I then used this new line and compared it back to Robert's original "after" dyno.

Looking at the "fixed" comparison, I think these figures are more correct. Peak gain of 4 ft/lbs, average gain of 2.9 ft/lbs across the entire RPM range, 3.7 ft/lbs gain in the 3k to 5k range (driving range). The 3.7 ft/lbs of additional torque is roughly a 2% gain in power in the highly used 3k to 5k RPM range.

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