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How to get better VE table from datalog

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I tried searching, but maybe I'm using the wrong terms.

I am on an FSAE team with a single cyl KTM engine. We have a Motec M150 an I have some experience with the Megasquirt ECUs. For the life of me I can't figure out how to dial in the VE table from datalogs, easily. Since the car is a single seat driving it around with a laptop isn't really an option and we are very limited on dyno time later and it would be nice to get ballpark close at least before that happens. I know with the Megasquirt I can upload the tune and the datalog into Megalog view and have it generate a "better" VE table and while the car is running the "Q" key in the VE Motec table works. Is there an easy way to take a datalog in i2 and have it adjust the tune with a "Q" key type function or table generator? I have megalog viewer pro and can open the Motec logs there, but can't figure out how to get the Motec "package" in there.

The race car currently starts and runs, but the previous team had zero idea what they were doing and it is the ugliest tune I've ever seen. I'd really like to make it better, but I'm stuck with using only logs for some time.

Thanks, and any help is appreciated

You need to use the L key (Lambda Was) within M1 Tune when you've selected a cell (site) in the Engine Efficiency table. Then you type in the values for Exhaust Lambda Normalized and Fuel Mixture Aim for a given cell and it will do the calculation and change the data. I suggest you make sure "Fuel Closed Loop Mode" is not in use (set in Engine Systems->Closed Loop Fuel tab). Another alternative, is to have closed loop fuel turned on, and change your Engine Efficiency Table by the amount of Fuel Closed Loop Control Bank 1 Trim. The engine will likely run better while trying to tune it initially if you do that.

What is hard is to actually get logged data with the car at steady state -- you don't really "cruise" a FSAE car, except on the dyno....

I might be misunderstanding the question, but it almost sounds like you're asking 'how does road tuning work'. It's a bit like an engineering lab course, but with different tools. You can plan ahead for what to test, gather some data during the test, analyze the test results to form conclusions, then make changes and repeat the test to see if your conclusions were correct.

Your test goals can be as simple as finding which VETable values are required to hit a certain target Lambda value at full throttle, or more complex like does a certain lambda target affect measured vehicle acceleration. Part throttle and transient throttle (acceleration fuel) is pretty important for autocross and endurance racing, possibly more important than extracting the absolute max power the engine will make at full throttle. Be sure the engine restarts well after running an endurance race, it's a shame to see FSAE teams fail half-way through that event.

Look at the road tuning course, or this webinar if your account has access to view it: https://www.hpacademy.com/previous-webinars/the-key-to-road-tuning-left-foot-braking/

Good luck and remember to pass all of your classes.

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