This is a question that seems hard to answer. The more I read, the more confused I get.

I have always heard that with intake and exhaust, one need to have something done. Whether it be download, tuner, or xieds.

So as I was looking at xieds, I read the FAQ and it said the opposite. Here is a link to the page http://www.nightrider.com/parts/ied_faq.htm
So basically it will still run as lean as it was from the factory, but no harm. Is that a correct assumption?

I know that it would be better if it was running richer, and I plan on getting a tuner. I just haven't decided on one yet.

So how do you feel about that statement that nothing is needed, or you will kill your motor.
Thanks for the help as always.

 

I have changed my intake and exhaust with no tune mod. I figured I would try it an see how it ran. I doesn't backfire or run any hotter than before. The way I look at it is you aren't actually changing the size of your intake and it can only take so much air in. Try it and see if it runs like you like. But I honestly don't think you will hurt anything.

 

If you add pipes and breather to a HD, the ECM will revert the lean condition back to 14.6:1. That is what the 02 sensors are for. However the lean burn 14.6 : 1 is still too lean, runs hotter and allows more unspent fuel out the exhaust.

It is the AFR that yields the lowest emissions which is why it is used.

For almost 100 years of engine science the 12.8 :1 AFR is the easiest to ignite, most complete burning and coolest running.

Your air cooled engine will run stronger and cooler at that AFR.

Last year American Iron did a test by installing an after market exhaust and air breather on a HD. The got more HP and torque. The EMC did adjust the AFR to the 14.6:1 ratio.

So yes a tune is not needed. But why run a lean burn AFR when it will run better at a proper ratio?