I will tell you this. Unless you hit the autobon, or find a steep hill, with a high output engine hitting 60 kpa is a major accomplishment. Since I could not hit 80 in the vtune sessions, smoothing from 60 would likely produce a more gross error in the ve tables than leaving it canned. That's why I didn't do it. Or another way to look at it is if you can't hit them, you don't really need to be concerned about them.
Ron

 

One Ron to another, Best answer I've heard in a long time!

 

You guys must be at elevation, haven't found it difficult at all to hit 80 kpa. Unfortunately I find that I exceed 80 KPA frequently, so the data isn't valid.

 

powerlab, i would go with the NI-176 for the 2-1 exhaust. You always want to go after the closest cam profile, then the closest exaust combo when choosing a starting map. You can always chage the injector size in tuning constants.

 

I'm looking at doing some more tunes on my '09 FLHR. We're headed into 110F+ days and I really want to cool my bike down. I dealt with constant pinging last summer and a couple of knocks. I've read that the stoichiometric ratio for E10 gas is 14.1 which is what I'd like to set my bike at. I think I'm around 740-760 mV right now. However, both Doc's and Mastertunes instructions say not to set it over 780-800. A 14.1 AFR would have me setting the bias around 805. How bad is this? How quickly will my O2 sensors crap out? Would it be worth replacing O2 sensors regularly (as a maintenance item) in order to save my entire engine from the ravages of the AZ desert heat?

 

Bluegrasser,

I don't even play an expert on TV, but your numbers don't make any sense to me. First, Stoichirometric is just south of 14.7. My tuner set mine at 14.68 to take into account the non-perfect world.

Maybe that is why the rest of your numbers don't compute, but a 14.1 AFR is pretty rich, though I don't know if its enough to create a problem. As I see it the bias would be set at 808/809mV for that. A bias of 740-760mV would result in a AFR of 14.6-14.53.

Again, I'm no mechanic, and an even worse tuner, so here is what my dyno-tuner set my bias tables at, and I couldn't be happier. The bike runs great, and yes we have some 100+ degree weather here.

Under 40, 50 & 60 MAP: 622, 603, 603, 603, 622
Under 75 MAP: 681, 681, 681, 681, 720
Under 90 MAP: 778, 778, 778, 778, 778

Remember that in open loop (idle & acceleration) your bike uses a different AFR map which will be richer.
Steve

 

Thanks for the help, Steve. I was under the impression that the 14.68 AFR was what the EPA mandated that HD use and wasn't actually the best AFR for the bike? The 14.1 number I came up with is just what I saw on various internet sources when I googled E10 stoichiometric AFR.

 

yeah I'm sure the EPA did mandate that AFR for stock bikes. That's basically a perfect burn, which is what stoichiometric means. I don't know how ethanol changes stoic., but I'm sure it does.

From what I gather, one doesn't need to go too rich in the closed loop area, because your bike is not under much of a load there. And during that same condition you are typically getting decent airflow across the motor. I believe that TTS has done a pretty good job in enrichening the AFR in the areas where cooling is more important.

Someone else chime in though if I'm not saying it right, or have something wrong.

Lonewolf176 is an excellent professional tuner with Mastertune, hopefully he can set us both straight.

Steve

 

I'm no TTS expert either as this is my first bike using TTS, but first thing I would do is contact whoever I bought TTS from and ask their advice. It kinda sounds to me like you might need to do some timing runs and adjust the spark advance to stop the pinging. But, like I said, this is my first bike using TTS.

 

If you want your bike set to 14.1 at cruise. Then, just set the AFR to 14.1 at cruise. Nothing says you have to stay in closed loop.