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Well here's the deal. I'll assume you have the software and the license, because if you don't you're not being forward thinking enough. On that basis, work out the K factor for the bigger injectors and the AFM, add 30% for E85, don't touch the timing. Fiddle the K factor (and the injector latency) until you get it to start and idle. Ideally check the mixtures at a light cruise with a wideband. Then drive it really gently to the tuner.

You will NEVER get a pre-done tune that you can just load up and drive merrily off to the tuner on. At best, even if beautifully mapped by the world's best 26 tuner, it will as like as not never even start unless you can adjust the basic scaling values yourself.

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Download the Nistune tuning guide pdf from their website. You're looking for the sections on how to recalculate k to account for both AFM changes and also injector changes. You need to read and understand that stuff, as if you were going to do it yourself, even though there is a built in function in Nistune (software) to do it for you nowadays. The reason you need to know is that you will probably get Nistune (software) to do it for you for the physical changes, but you will need to know how to then mod that number to account for E85 (ie adding that 30% extra fuel).

Short answer, you make k 30% bigger just to account for the fuel change.

If I were you, I would definitely read the Nistune forums also, with respect to looking for specific instances where people are just converting to E85. There's probably a few extra tidbits hidden in there about what extra things you will need to do and which extra things you might do won't help. That sort of thing.

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Thanks that info is awesome and just what I was looking for. There's only one nistune tuner in the entire state of Texas so most help I get is from the GTRCanada forums. Since there are only about 2 or 3 E85 stations in Canada, there is not much help for tuning for it.

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