Post by thebeaver on Jul 1, 2010 17:27:02 GMT -5
Well, I wanted rebuildable 1.5" straight through pea shooters for '78 standard, and couldn't find what I wanted. So, I decided to build a pair. I hand formed the cones from 20ga stainless sheet metal I got from the scrap yard, and I cast the end caps from a melted down BMW head (also from the scrap yard).
my understanding is that keeping a constant ID through the muffler tricks the engine into thinking the header is that much linger (24in in my case). This would increase low and mid range power. So that's what I did. The perf tube is a little thinner wall, but otherwise, everything matches up perfectly.
I just took it on it's maiden voyage today, and the result was phenomenal. I had pod filters, Mike's 750 kit, Boyer ignition, and 1.5" Mac headers, and crappy generic reverse cone mufflers (Emgo I think). The bike was quiet and had little more power than stock if any. Now I realize that it was the restrictive mufs that were holding me back.
The bike is now a monster. Power throughout was dramatically increased (especially in the mid range). The sound and vibrations are so sweet too. At idle, it's super quiet, but cracking the throttle produces quite a roar.
I would highly recomend this kind of setup, but for god sakes, don't try to build 'em yourself. It came out great, but it took way too long.
yfrog.com/0ymufconstructj
yfrog.com/0ynewmufs1fj
yfrog.com/0ynewmufs2j
my understanding is that keeping a constant ID through the muffler tricks the engine into thinking the header is that much linger (24in in my case). This would increase low and mid range power. So that's what I did. The perf tube is a little thinner wall, but otherwise, everything matches up perfectly.
I just took it on it's maiden voyage today, and the result was phenomenal. I had pod filters, Mike's 750 kit, Boyer ignition, and 1.5" Mac headers, and crappy generic reverse cone mufflers (Emgo I think). The bike was quiet and had little more power than stock if any. Now I realize that it was the restrictive mufs that were holding me back.
The bike is now a monster. Power throughout was dramatically increased (especially in the mid range). The sound and vibrations are so sweet too. At idle, it's super quiet, but cracking the throttle produces quite a roar.
I would highly recomend this kind of setup, but for god sakes, don't try to build 'em yourself. It came out great, but it took way too long.
yfrog.com/0ymufconstructj
yfrog.com/0ynewmufs1fj
yfrog.com/0ynewmufs2j
