| Author | Message | ||
     Slitherin |
Looks like I should have posted my question in this section vs troubleshooting. http://www.badweatherbikers.com/buell/messages/384 2/287328.html?1182948615 Anyway, 2 basic questions. 1. Just running the race pipe should not affect the mixture right? I'm running a stock setup now with the race pipe. I should just get sound out of that right? 2. After the race ECM didn't give good performance I swapped back to the stock ecm for 2 days. Do I need to reset the TPS again if I want to run the race ecm again? | ||
| Bad_karma |
John The experts will be along shortly, but I believe that changing the ECM requires a TPS reset and running at 3k for 5 minutes for the ECM to set parameters Joe | ||
| Al_lighton |
Just running the race pipe will absolutely affect the mixture, especially in the top end. The bottom end of the race pipe and the stock pipe aren't dramatically different. Their curve shapes are similar, and the absolute values fairly close. But above 4500, the race pipe is a monster, the stock pipe less so. The race pipe needs a fair amount more fuel up top. But since the response isn't tremendously different across closed loop learn, the AFV scalar will NOT make up for the lack of fuel up top. It will be lean, and run hot, and possibly damage stuff, if run hard on the stock ECM. Running the race pipe without the race ECM isn't a great idea, especially if you ride it hard in the top end a lot. In closed loop, it won't make a lot of difference either way, the O2 sensor will compensate for the little bit of difference there. The bike will run, ON AVERAGE, at 14.7:1 in cruise on either ECM. You don't need to reset the TPS if it was set right to begin with. The value is persistent. Al (Message edited by al_lighton on June 28, 2007) | ||
| Slitherin |
Thanks Al. So do you have any advice on why I "feel" a flat spot with the Race ECM between 3k-4500? And you're also saying that the stock air, stock fuel, but with a race pipe will let it run lean on the top end and be dangerous? Thats bad because I'm often at the top end. I've got a track day coming up in just over a week so I should go back to the race ecm and deal with the flat spot? Also the TPS will be ok after going back to the race ECM. I'll try to scan the Dyno sheet and post here. The interesting thing is that the curves are almost identical but the flat spot is definitely there with the race ecm and K&N even though it isn't on the chart. | ||
| Al_lighton |
I can't say why you're feeling a flat spot that doesn't show up on the curves. I tend to trust curves more than my "butt dyno". "Butt dyno's" are notoriously inaccurate. They tend to notice rate of change of power more than actual power. Neither the stock pipe nor race pipe are stellar in the 3-4.5K range. Most of the dyno plots you'll see on either will show that to be their weakest point of operation. The stock and race ECMs were designed to fuel the stock and race pipe respectively. If you look at the curves in the exhaust shootout for the stock and race pipes, you can get a good feeling for what the maps in the stock and race ECMs are trying to feed. I assume that you're talking about WOT operation across those RPMs. I've got the maps for both at work, I can compare the fueling to see how different they are across that range in the WOT TP column. Al | ||
| Mwbob |
Al- Just out of curiosity, Will the ECM cover the fueling needs of an XB12Ss, stock air and a D&D pipe during closed loop operation? I'm sure that it would have problems at higher RPM and possibly large throttle openings in the midrange. As I've talked about on other threads, my TFI seems to do a pretty good job in open loop mode, but closed loop operation is constantly changing. Perhaps I should let the ECM have control of the closed loop mode without interference from the TFI. |
