Jayboy

How off would the blue box be with a ported z6 head with 31o's +walbros. Am i running lean?. I know the box is for 240's (SOHC blue box) but i have the fuel pressure at 37. Only reason I'm asking is because my autometer gauge starts slowly spreading from green to orange, i'm talking like 6-7 bars lit half green half orange, get it?

dustin

We have no way of knowing if you are running lean...

Jayboy

I know the gauge sucks but its a temp. The thing is the gauge has only 3 green lit when i start to boost and by redline its like 3 green AND 2-3orange. i just dont know if the porting has anything to do with it. thanks

dustin

Well the O2 sensor isn't accurate at anything past stoich... so anything we tell you is just an estimate.

For what it's worth, when I've had my cars tuned at 11.5:1 AFR, the "light show" autometer gauges always pegged themselves rich (last green light).

So yes you may be running lean, but I have no way of knowing for sure. How much boost are you running? what motor? greddy kit?

Jayboy

Its a completely built z6 wiesco 9.1, eagle rods, ported head/IM blah blah blah and running a greddy kit with about 8psi of boost. On the fuel side is a walbro, 310's adjustable fpr base 37psi. The thing is How could I be running slightly lean though? I thought the blue box was supposed to make it extremely rich throughout boost. Maybe I'm running so rich that the autometer, being stupid and inaccurate, shows a bit in the orange? But its never pegged in the green, only like the first 3 bars from stoich. The main question is does the ported have a significant effect on how much air is being forced in? Enough to make the motor run slightly rich? Its wierd. Wideband is coming but just not soon enough!

to the people that are answering my questions

boostincoupe

You should be fine. Don't up the fuel pressure too much though, it's alright from about 37-40 psi or so.

The blue box's A/F ratio is tuned by boost level, and nothing else. It maxes out the injectors when the MAP sensor reads boost, so at 5 psi, you're rich, 10 psi you're stoich, 15 psi....BOOM!

EDIT: Oh, and **** that Autometer A/F gauge with a midget's ****.

Jayboy

You think because i upped my fuel system (injectors 22% bigger than stock) I should reduce my base FP by 22% (since the bluebox is essentially controlling the 310's at the 240's pulse-width)? That would leave the base setting at ~30psi. Maybe that was why it bogged so much at WOT, too rich? Its weird because it pulls harder under part throttle full boost compared to WOT full boost. Why is that?

Throw me a bone

Jayboy

mmm