[W126 Coupe] tornado air twister

[Jim Nowak]

14.7:1 is stoichiometric.  That's ideal for emmisions
but not ideal for power.  For maximum power 13.5:1 is
ideal.      

http://www.kennebell.net/faq/faq-answers11%286%29.htm
http://www.carcraft.com/techarticles/116_0402_tune/

Jim
     
--- eurotech1 at charter.net wrote:
> 
> Hi Jim,
> 
>   In the case of a 318 BMW we turbo'd at the shop I
> worked at, we had to remap the fuel map in the
> ECU.We used a H-P laptop with a USB to diagnostic
> connector cord. We connected the connector to a
> piggyback computer on the BMW ECU. The piggyback
> overwrote the original fuel map with a program from
> Underdog Racing Development we used to remap.
> We read the air/fuel ratio with a wideband sensor
> display unit from Innovate Motorsports. As you know,
> 14.7:1 is the ideal air/fuel ratio for a gasoline
> engine. At higher RPM at the top end of the boost
> (18 lbs.), we set the mixture at 14.3-14.5:1 (a hair
> richer) to prevent a lean condition at WOT. Tuning
> the fuel map made a world of difference, as a matter
> of fact, the brand new BMW clutch and pressure plate
> were starting to slip at about 3500 RPM , the motor
> was producing so much torque. A Centerforce six-puck
> racing clutch and pressure plate took care of that.
> The 1.8 had a pair of cams from Web-cam, Rossi 8.5:1
> pistons, rods were stress-relieved, the turbo came
> from a 2.0 Buick Skyhawk, and used a Jackson Racing
> dump valve. Used Innovate's electronic boost control
> unit, with an indash control center. On a Dynojet
> dyno, it did 307 hp at 6200 rpm at 20 lbs. of boost,
> with a 50 shot of nitrous at 5800.
> That was a fun car!
> 
>                        Later,
>                        Chris
>