panic

i'd like to know how you tune a C6 after adding performance mods... what method, what hardware is used. i live on the other side of the pond (going east ) and much probably will buy my C6 soon which i'll mod and i guess i'll have to tune to optimize its performance...
thanks, all contributions will be appreciated

HITMAN99

Very little hardware is involved, it's almost all software. There are a couple of different methods generally used, one is dyno tuning, the other is street tuning. Both methods require that you have some sort of tuning software such as HPTuners, EFILive, or LS2Edit.

Dyno tuning has some advantages. Typically, a wideband oxygen sensor is inserted into the tailpipe to measure the air/fuel ratio. Wideband sensors are much more accurate than the O2 sensors built into the car, especially at wide open throttle. Data logging software is also used to capture other parameters such as the spark advance, throttle position, injector bandwidth, knock retard, etc. The car is then run through a WOT pull in 4th gear, starting at 2500-3000 RPMs. After the pull, the tuner reviews the data logs, then changes the various parameters to add or subtract fuel, advance or retard the ignition, etc. Then another pull is done, and the results checked. This can go on for several cycles until the tune is optimized. The disadvantage of dyno tuning is that the "load" on the dyno is not exactly the same as the load on the street, and neither is the airflow.

Street tuning is similar, only the pulls are done on the street. Since it's not so easy to go 115 MPH or so on the street, this can be a problem. Also, data logging is not nearly as accurate using the factory O2 sensors. However, on the street it's easier to log data under a variety of conditions, such as part-throttle acceleration in the lower gears.

The tuning software can do many other things besides adjusting the air/fuel mix and the spark advance. It can disable torque management, eliminate the "skip shift" feature, turn off error codes, adjust for aftermarket gears, change shift points and firmness, etc. There are literally hundreds of data tables an parameters involved, many of which are interrelated.

The only hardware device that I am aware of is the Diablo Predator, which is a handheld device. It can change a few tuning parameters, but is very limited in its capabilities compared to the tuning packages.

panic

thanks jitman for all these infos...i remember many years ago when first time was launched the mitsubishy gto twin turbo, right after colect from dealer i drove her right to a northern italy top tuner, the guy after making quite a few mods went for a drive with a passenger holding a computer and when came back was geting dark and i noticed the brakes were red hot...i guess this was a driving tuning then.

what about the chips they sell aftermarket? like the english superchips...could one of these be used on a modify C6 without taking the car to a tuner?

thanks/Giu

HITMAN99

Chips don't work on later GM cars that have powerful engine control modules (computers).