If you think about the design and its intended function....it was meant to improve performance on much older engine designs, and has successfully been used on various muscle cars, etc...but with the current fuel delivery systems....what can it do? The systems essentially have made the old mod obsolete.

I personnally have felt that any mod that makes more noise when you hit the gas just seems faster...I think its a common impression most people get...the first time I got a hole in my muffler and sounded like a dragster, I could have sworn I had new found power....but being a grease geek, with access to test equipment, etc...I was able to prove to myself that I was wrong about the increase in power, but right about the impression of increased power.

The dyno showed no measurable difference....and....

My 1/4 mile times on the muffler hole were no better than the muffler whole.