Flex Fuel E85 on e46 M3/BMW S54: Bosch Green Giant to max performance!!! we go to E71 Ethanol level

Can go all the way to E85!!!!  based on Injector Duty Cycle, but you need the right fuel pump to deliver.  I have done this previously.  The pump has to cover the higher flow rate for E85.  That is posted here      BMW e36 Fuel Pump 340 LPH upgrade rev....  I have since swapped to a duel fuel pump setup for fuel starve reasons.


The OEM injectors are not sized to allow full use of E85.   Plus they are from 2002 and had 150K miles, and one did not clean well.  SO I bought an aftermarket one.  This is a future reliability concern.  Track Toy needs new stuff,  fuel is important!

BUT, how?  Calculations online say something over 42lb/hr or about 440cc/min will do the trick.

Low and behold Bosch Green Giant at 43lb/hr will work, have a dual cone spray, and maybe will allow a good idle.  It seems if you buy very expensive and very large injectors you will have a problem with idle.  I had no idea if these would work.  But they are a relatively inexpensive option!!

I found an injector hat that would work from __injector rehab___ for the fuel line feed.  It has a filter so I drilled that out.

In the end using the APE-X85 Flexfuel app I was able to easily start the car and drive it by using their _____ RPM band and Fuel Multiplier _____ feature for initial injector sizing vs. ECU tables.  I did get the ECU tables fixed later but this made it super easy!

Additionally the APE-X85 logging feature illustrated graphically that I could not max out these injectors all the way to E85 as E64 was below 50% for the most part on duty cycle.

Honestly based on these numbers these injectors are still a little oversized.  However these work really well and are highly recommended!

The biggest issue to overcome was the mechanics of the fuel line feed.  SOLVED!