New Exhaust

Just wanted some input on a new exhaust. I have python slip on mufflers right now. They are ok but noticed that the right muffler gets very hot and the left muffler doesn't get so hot. I wanted to go true dual but don't think my cobra tuner will work with a true dual set up. I like the looks of vance and hines pro pipe that comes out this February. I've heard that a 2 into 1 gives better torque. The SG could use more torque. Any input would be appreciated.

Kevin

Your Cobra tuner will work with dual exhaust, just not as good as it could with a different kind of tuner, I had mine on for a short while and it worked OK I then put on my Thundermax and it was like night and day, I would say if you want dual exhausr go for it, I like mine and lots of less heat and sounds awesome, Todd

That's 'cause only part of the exhaust from the rear cyl. goes down the left pipe - more goes down the right, as well as all of the exhaust from the front cyl.

Others can help you with the tuner issues, but I can tell you that the Pro Pipe is a poor performer. I'm reminded of a Dyna that had a V&H Pro Pipe & switching to duals picked up 13 HP right off the bat. I was leaving the place where the dyno tuning was being done so I don't know the end results, but the 1st thing that was done was to pull the 2-1 pipe.

Also, all 2-1 pipes have a torque dip in the 2500 rpm range & the powerband they work best in is just 1500 rpm wide - typically 3000-4500 rpm. But that's the range a lot of people ride in & with some tuneable pipes like the SuperTrapp, you can move the range around a bit.

Look @ a typical 2-1 pipe & unwind the rear pipe in your "mind's eye" - it's longer than the front pipe, isn't it? And since anytime you put a bend in a pipe you increase the effective length of it, it's even longer than it looks. But a Harley is an "odd-fire" engine & even if the front & rear pipes are the same length, the exhaust from the front & rear cylinders hit a 2-1 collector @ uneven intervals.

However, by tuning pipe length, diameter & collector design, you can make the engine think it's an "even-fire" & make each cylinder help the other. But you can only do that in a limited rpm range & given the basic design of the motorcycle, you're limited as to what you can do - otherwise the bike will look goofy.

So you end up with a compromise of style, sound & performance, with different brands emphasizing different characteristics - in other words, this one may look great but perform poorly; that one may perform well (in a given rpm range) but doesn't sound that great, etc. & it boils down to what's most important to you.

Art:

Thanks for the info. I will post a link of the new pro pipe that will come in Feb next year. It says it has a tuned length to make both pipes about the same length. Seems i heard somewhere that if I do true duals and keep my cheap tuner that the rear cylinder will run hotter since I can't change the adjustment on the rear cylinder only?

Vance & Hines: Performance Exhaust Systems

I like the look of duals. This winter I am putting on a set of the dresser duals and the monster oval slip ons.

That's all well & good & looking @ the website they mention using a "stepped" pipe design, which you can do lots of things with, but unless you can convince God to change the laws of physics, you're still going to end up with a powerband that's about 1500 rpm wide - cylinders helping each other in the 3000-4500 rpm range. And that 2500 rpm range torque dip is still gonna be there. But you can tune the bike so the "seat of the pants dyno" says it's not a big deal.

And if you normally ride in the 3000-4500 rpm range anyway, you'll be right in the range that the pipe works the best. Pipe makers for big twins usually focus on throttle response & pulling power on the highway rather than stoplight-to-stoplight acceleration, simply because the goal is to be able to pull out & pass without having to downshift. If you like that pipe & it fits your riding style, by all means get it. I personally don't like 2-1's, but I'm a Sportster nut & run in a different rpm range than BT riders.

That I'm no help with, but there are a lot of BT riders here who are familiar with the different EFI tuners.

I already have the mufflers so sometime will get python header pipes and be done with the cross-over. Hope it does not hurt the torque to much. Seems anything less than 3000 rpm the motor starts to labor. Would like to install a better tuner and cams sometime in the future.