My car is running precision 1200 cc injectors on E85 right now.....My pump map is scaled to 770 and my e85 map is scaled to 539. Im assuming this is why my car will go stupid lean at one stop sign then stupid rich at another. If I start uping the scaling to get my trims within +/- 10% how much will this change my WOT tune?

Thanks

 

Read the "fuel trims" thread in alternative fuel section. That should clear some things up.

 

thanks that thread helped quite a bit, any idea how much I'm gonna have to change my fuel map after rescaling?

 

If you change your injector scaling correctly, you will only have to adjust the map to mimic the flow vs. duty cycle curve of your new injectors.

 

I'm assuming you don't have a wideband or evoscan. Your best/safest bet would be to go get a basic dynotune where a wideband is used(or a road tune w/ a wideband). That would get you really close to optimum performance and reliability. I recommend a wideband with a link to evoscan so you can learn how to do it yourself after you've done some research on consequences of changing whatever map you're changing. Those two options are really the only true way of knowing what your car is doing on a wot pull and daily driving conditions. Enjoy the can of worms you've opened up to yourself- it's a lot of fun but time consuming.