So I went with the american custom header and slip ons. The mechanic at the dealer tells me I need to have a dyno done on it. Is that true? Also, do I also need to get some kind of tuner or will the dyno be enough to get everything right? Thanks in advance.

 

Not sure from this what year we're talking about, but you could have the dealer flash the ECM. You'll get varying opinions on the effectiveness, but it worked well for me (I flashed it myself). I just added after-market muffler and a/c. Now I'm replacing the head pipe, and still plan on a flash first to see results.

 

I did the Heavy Breather with V&H Dresser Duals and Monster Ovals slip-ons.
Had the dealer do the Stage 1 download flash to the ECM.
Everything runs great.

I did this same thing to my Sportster and it ran great and got great gas mileage for the 3 years I had it.

 

I've install two rush mufflers and wanted to remove my cat from my stock exhaust then install a heavy breather. Instead of installing a fuel system or the XiED I went to my local H-D dealer and explain what I wanted to do and ask if they could do some type of down load instead of using a fuel system. They said H-D no longer is allowed to do down loads. My bike is a 2012 street glide. So I guess I will have to use some type of fuel system or XiED to make my changes.

 

I think they're giving you the run around.
I just had the Stage 1 download installed on mine last month and my freind just had the SE Race download installed on his a couple weeks ago.

I would check with another dealer.

 

Sorry. It's a 2012 Ultra Classic.

 

I have the Pro Tuner from Harley, and can do the download myself. Finishing up my new headpipe (fuelmoto without cat) on my 2010 Road Glide, with SE a/c and SE Muffler. Planning on flashing the ECM this weekend.

 

If you want to know that you got maximum performance from your modification, you may want to consider a SERT (or some kind of tuner) and a dyno. Otherwise, it's just, "I hope all this stuff is working the way it's supposed to". Anyway, that's what I did.

 

Do you NEED a tuner? No. Your sensors and ECM will adjust to AC and pipes. Your bike will not blow up.

However, if you want it to run a bit cooler and/or get more power you have a range of choices, the more you spend, the more perf you get. XIEDs are a cheap way to richen it up a bit, but various fuel management solutions combined with a tune would give you optimal performance.

 

when changing from stock headpipes to aftermarket pipes on a 2012 I would recommend tuning. There are options that only require a download map for the system and eliminates dyno time expenses. It's generally not as good as a dyno tune but they still work great. The main benifet of dyno vs a fuel management system with a map is squeezing out every last bit of power and having a smooth curve. If you just want it to operate properly the download maps work great.