i have a hrc stage 2 and i know this is bad but what does running lean mean...and how do you know if you are and how do you control it. i just replaced my transmission and i don't want to have to replace my motor!!! please help and do yall think my transmission broke because of the extra hp from turbo...just wondering??? thanks

LAST EDITED ON 07-Jan-01 AT 11:49 AM (PST)

Well, it's easy actually. Running lean is when you have less than a Stoich mixture (proper fuel and air mixture) in the combustion chamber. Rich is too much fuel. Rich can lead to clogged cats, foiled plugs, O2 sensors, poor gas mileage, less power than you could ultimately achieve, but a safer than lean condition for a less likely chance of detonation. Lean is great for faster runs, but increases chances of detonation (i.e. new motors). An A/F meter is a way to see if you are running lean of rich. A better way is an EGT guage. The leaner you are running the hotter the exhuast gas temp. This can lead to cracked or melted pistons or blown rings. A fuel pressure guage is good to monitor your fuel to boost ratio. That is gonna be the next guage I get. I already have A/F, EGT, and Boost gauges.

There are several ways to control... Most importantly supply enough fuel... Either turn up the Fuel Pressure or turn down the boost. Also, bigger injectors is another way, but sometimes (depends on how big you go) requires something to control them (i.e. Super AF-C).

If you are really interested in learning more about your turbo, or turbos in general, get the book Maximum Boost by Corky Bell. Very informative and a MUST HAVE for any Turbo inthusiast.

Good luck and hope you get it ironed out soon...

Later
DoN

'99 GS Sports Edition
Star Stage 2, CFDF Clutch
Greddy Manual Boost Controller
Greddy BOV and EVO Exhaust
Greddy TT and shift knob
AF/X UDP
B&M Edge Short Shifter
Eibach Sportlines with Tokiko Blues

'99 Eclipse GS Sports Edition
Star Stage 2
Greddy EVO Exhuast
AEM Big Brakes
Greddy Type S BOV
Pioneer DEH-P7200
Bazooka EL1500 running 2 MTX 10" Subs
Fosgate Separates throughout