Air to fuel ratio gc8
 

Any advice how to check my air to fuel on my gc8 I don't have a guage wondering could it be done via obd port or any other method ?

I personally use a wideband lambda and gauge to check my v3 GC8
I know you can replace the narrowband sensor and hook up the wideband in its place then log the voltage data in ESL then convert to get AFR,so maybe on the later v5/6 you can do the same with the oem ECU?
Or possibly converting the maf voltage data(in open loop) and lambda(in closed loop)into AFR is possible but I couldn't say for sure :wonder:

Cheaper to find a rolling road and get a health check run done.

Can it not be done via diagnostic port in flight mode

can't do with OBD port - the car doesn't have a way to accurately read the air fuel ratio on boost. You could read the stock narrowband output but it will just be flicking between rich/lean all the time so not really of much use to you.

JDM Stig has nailed it, find a local rolling road who can do a dyno run and provide an AFR plot at the same time or if it's just for setting emissions up then most garages that offer an MOT should be able to check and report on it.

Think It's gotta be a dyno run just wondering if I clean out the tail pipe from inside will that give a idea if lean or rich you think ??

You could whip the plugs out and check the state of those, this gives a indication of the mixture, no where as accurate, but is a guide.

Are you interested "just to know"? Or do you think there is an issue.

If you think there is an issue then putting it on a dyno is not a good idea, the issue could well bite, and your car will struggle with cooling on a dyno having the tiny slanty top mount intercooler
If its decatted the tail pipe will always be black and that no indication.

Get someone with proper wide band kit to put that onto the car then drive it in a varied way using throttle controlled load levels, that will give you the true indication.

If it gets toasty on a dyno (almost guaranteed) then the oem ecu will simply throw fuel in for safety and you won't get a true picture at all

If you do check plugs make store its after a decent run before starting it again when cold

This is actually for version 5 type ra it's been imported last year running oem ecu decat has a manual boost controller just want to make its safe when driving because I'm putting it up for sale shortly

The slanty one is chilling for the moment need to get this one gone then I can concentrate on the v2