GStwin.com GS500 Message Forum

Main Area => General GS500 Discussion => Topic started by: jefferygs500 on March 30, 2005, 06:22:51 PM

Title: Holes in the back of the muffler???
Post by: jefferygs500 on March 30, 2005, 06:22:51 PM
hey,, i see you guys talking about drilling holes in the back of your muffler and it makes it louder??? i don't think soo?? Or for mine it nevered... I put 7 holes 1/4 bit. Any suggestions??
Title: Holes in the back of the muffler???
Post by: V8Pinto on March 31, 2005, 06:40:26 AM
I started with four 1/2" holes, then drilled 4 more.  That's roughly .2 square inches of area per hole, and 8 holes for 1.6 square inches of area.

You holes are .049 square inches * 7 holes gives you about .34 square inches total.  

I don't think you have big enough holes.  area goes up by the square so even a little increase in the hole diameter will make a large difference.

I could feel the performance increase when I drilled mine.

I might have gotten the math wrong, to much "fun" in my twenties...

:cheers:
Title: Holes in the back of the muffler???
Post by: cozy on March 31, 2005, 03:11:05 PM
I did it. 8 5/16" holes. Too farty. With my ignition advancer it felt like i was losing power. i did't like it and have since gotten a wileyco from Dennis Krook and ordered a flange from Sinrath. I rejetted with 127.5 mains and 40 pilots.