Hey all, just got my bike all re-assembled and getting it ready to hit the track. It's an 09 ZX6R. I had the head milled by just 18 thou and degreed the cams to 107.5 in and 110 ex. I've installed a Bazzaz ZFI-QS and I also have the AFM module and O2 sensor. This is my first time utilizing any of this equipment so I was curious as to what the optimal Air/Fuel ratio's might be through the RPM range. I plan to run 91 pump or U4.4. Any advise and the reasons for it would be greatly appreciated!!
IMO you would get the best results with a trip to the dyno first. Then you have your best performance baseline and go from there. JMO Tdub
My plan was to take it to a trackday to get a baseline with the auto tune, then do a couple dyno runs and maybe smooth the map then. I'm new at this though.....
You should take it to a professional dyno tuner first. Get a custom map built, have the tuner find out which A/F ratio makes the best power for each fuel and have a map built for each. I can tell you that pump and U4 have different optimal A/F ratios, and the maps are significantly different - it's quite a bit of trim that each map would need to convert back and forth. 0.018" is a lot of material to remove. Are you using a thin head gasket as well? Do you have standard spark plugs in it? Can you adjust ignition timing?
Stock gasket, stock plugs. Not sure about ignition, dont know that much about the ZFi-QS. I got the AFM because I thought it would negate the requiremnt for a dyno tune, but of course I know the best results come from an experienced tuner. I'm not looking to ring every ounce of performance out of this thing, I'm not very fast. I did the engine work because I got a great deal on the machining and I was pertty much looking to learn a bit more. Basically in the original post I was just looking for some guidlines if anyone has them so I can put the #'s in the bazzaz system and take it to the track and ride it on whatever fuel I decide on, likely 91 pump. Then I was planning to put it on a dyno just to see what it will make, and then maybe have a tuner adjust the map accordingly.
It's not about wringing every last ounce of performance out of it necessarily. It's about making the most useable power curve. With that in mind there is no optimal A/F ratio so to speak. There is the optimal A/F ratio for your specific bike, modifications and fuel grade. Tuners don't tune the bike so they maintain a generally accepted a/f ratio across the board, they tune to achieve a smooth horsepower power and torque curve with no dips or spikes in it, and whatever the A/F ratio ends up being is what it ends up being. This could have the A/F ratio varying all throughout the fuel table. It's interesting because I was reading an article about how they tune MotoGP engines. They said that most untuned MotoGP motors create wildly erractic powerbands with huge spikes that would basically be un-rideable by most pilots, but they use electronics to tune the fuel and ignition maps (in real time) to create a nice smooth power curve that the riders can utilize. As you can imagine the same thing is taking place...A/F ratios that are constantly changing and being monitored to keep the power delivery smooth and useable.....not necessarily just shooting for the absolute highest HP numbers at all times.
yes I understand how it works and that every bike is different for a multitude of reasons, I was just curious as to if someone had a starting point they usually go by and then fine tune from there. I just want to ride the thing in the next few days and was looking for an acceptable starting point is all. Thanks for all the input
Well, I think for the less ambitious (and/or knowledgeable) tuners that just throw your bike on their Dynojet with Tuning link to put together a map in 15 mintues they just shoot for something in the 12.9-13.2:1 A/F range.
Thanks for all the input guys, much appreciated, I'm gonna do a little spariment' I'll set it up for 13.0 and run it for a day with the auto tune and make a map that way, then I'm gonna have it dyno'd to see what numbers it'll make, then have the tuner customize the map and see what #'s he comes up with.
