View Single Post
      01-30-2013, 07:57 PM   #23
CT335xi's Avatar

Drives: 2014 x5 50i, 2005 evo 8
Join Date: Dec 2011
Location: Newtown, Ct

iTrader: (0)

Originally Posted by Ænema View Post
CAT(charge air temps) are the same thing as what we usually refer to as IATs. For me it is more accurate to talk about IATs as pre turbo and CATs as post turbo, but that's just me.

You are correct with your line of thinking, however in application it works a little differently. The DME follows timing correction tables that will target lower timing advance the higher the CATs climb. It doesn't matter if you have 100 octane/e85/Q16 or whatever else in the tank the DME will still target less timing, it does this to prevent the CAT induced knock you're talking about because it assumes you have 93 octane. At that point, all the e85 can do is just prevent timing corrections.

That's why getting the BMS back end flash is a good idea, Terry(probably) makes changes to the correction factor tables to reduce the effect they have.
I see what your saying. What is this BMS back end flash? Is is a special JB4 or does Terry have to actually flash your ecu? Thanks
2013 x3 35i fully loaded with M package (sold)
2014 x5 50i msport (stock) 368 awhp/ 417 awtrq
366 / 428 awtrq - mustang dyno