Very good write up, are you going to do one on ignition timing?

 

Ignition timing is somewhat more difficult to do with clear cut screen shots. This motor has the only logical timing plot I have ever seen.

In this plot MAPxRPMxVE is the airflow and Ignition Advance is on the vertical axis. Notice that there is a clear pattern to the graph. This map was developed by the dyno gurus at Motec on the bosses personal motor. It is unlikely this pattern I found is a coincidence.

http://www.nbs-stl.com/MLVDemo/255%2...otIgnition.png

this screen shot is even more telling as to what they are doing.

http://www.nbs-stl.com/MLVDemo/260%2...IgnitionTp.png

Andy

 

They start at 10 and advances to 41ish (evidently this is a turboed or am I misunderstanding the manifold pressure?).
Folks on this thread including myself don't have close to the tech knowledge or the equipment to put that knowledge to use.
Some of us don't even have access to a good tuner, so trial and error using the butt dyno (old school) seems to be the norm for some, present company included.

It kind of sucks wondering how much unburned fuel and power you leave behind not knowing for sure whether or not your timing is fully optimized.

 

That motor is a supercharged 1500 cc marine motor pulling close to 300 hp on about 11 lbs of boost. Right at 180 KPA.

Andy

 

Andy, as an exercise I will. That would be interesting. The tune I'm running is actually a FuelMoto tune that Jaime did for me when they did my build this past February.. and although I see a spark event once in a while, I never really hear it, or feel any indication of actual knock.

However, what I see every late fall (late October/November) here in New England is a definite change in the number of events recorded and I'm pretty sure it's a change in the gas ethanol mix the gas companies hoist on us in the winter months, at least this is what I've been told.

It's been quite cold here lately but the bike isn't away yet, so I might get out this coming week and I'll do a log of the standard channels. I'm not really thinking I have a problem with the tune Jaime did for me, but a 2nd one for this change when the weather turns might be good.

 

Thank you Oldhippie,
I have been reading pretty extensively and while I feel I am starting to get a better understanding of some of it, I am still puzzled by other parts. I am an IT Engineer myself, so I understand excel, and I log often. So a few questions I have:
1. We are told to auto tune to get the VE tables dialed in, but then we are told that we sometimes have to edit the VE tables.. So what I dont understand is on every tune I have looked at that has been sent to me for my bike, the VE tables are much larger numbers than what I get with Autotuning....I have a friend that is very good at tuning and has really made me some great tunes, and those tunes also have much larger numbers in the VE tables...

2. I know how to edit the PVV files to make them work in PV LT, but not really sure if it is helping much. I get the feeling it doesnt tune for performance, on efficiency and optimization. If I want a map that is really strong on the bottom (2200-4000rpm) when you roll on the throttle, how can that be achieved with a tuning software that doesnt appear to allow for a specific power result?

I actually tried "my Tuner" and its pretty much the same as the PV LT...as I can see.. I was going to buy it, but it will NOT let me...it crashes on every machine I own.. including work machines.. So I gave up.. I digress..

2007 Screaming Eagle Road King 110ci
Stock Heavy Breather (so they say)
No engine mods (255 cam, etc)
V&H Slash Cut rounds, V&H stock baffle.
Fulsac True Duals Conversion
PV2 (Powervision) All of my PV software is current.

Thanks guys.. I just want to learn more about what is actually happening. I am with many of you when I say, I am pretty smart LOL...and I cant really make heads or tails of MLV graphs either..
Glen

 

Glen

See if this helps out on getting your head around tuning.

www.nbs-stl.com/tuning/BasicTuning101.pdf

Andy

 

I have read this a couple of times. While it explains a lot of the mechanics and o logic behind things, it doesnt really translate into baselines and where to go, what to change, how to change etc.. But its a very good write-up with lots of good information for thought. I dont own a copy of MLV and until I understand more about this process, I cant see buying it yet. I really appreciate all the time you guys put into this and helping other people..
Thanks
Glen

 

Reading to learn about tuning a motor is is like trying to read and learn how to ride a bicycle.

Andy

 

Glen

Do you understand what a Target AFR is? Do you understand how to read the Target AFR Table?