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WhiteFinish wrote:Is it normal the AFR will change all the time?

When i'm just cruising when engine is normal temperature and just normal music level on my afr will change all the time between 14.7 and 15.5

Mine does exactly that, if not wider fluctuations. Hope it is normal

wytbishop wrote:What does the cookie do?

You gotta eat eventually...

nos92mx3 wrote:
Af ratio should be where the engine will idle smoothly but not overly rich. My car idles comfortably at 16-1 afr
crusing and under light load is basically the same idea lean, but not overly lean, id say crusing at a constant rate of speed, say 55 mph shoot for 14.7 (the stoichmetric rate for gasoline, up to 15-1, possibly leaner but i wouldnt try it without being able to detect knock and alter timing)
WOT rich best torque is made at 11.8-1 , lean best at 12.3-1.

So if I would run WOT under 11.8 i'm still running rich and I have to screw down the fuelpressure?

need to know more about your car/setup/driving style.

KLZE highcompression
Curved neck intake manifold
KL31 Camshafts
KL31 ECU
Aasco flywheel
Clutchmasters clutch
NGK Irridium plugs BKR6EIX
Cold air intake in combination with a universele open airfilter
Magnecor ignition leads
MSD digital window switches
Outlaw thermal spacers
Aeromotive AFPR

XS-power headers
65mm middle exhaust
65mm cat replacement
Custom double exhaust
Engine mounts filled
Short shifter
SRD Bushing & Bronz oil Bushings

Nitrous, at the moment 50 shot, will go to a 100 (with a walbro)

My drivingstyl is sporty. Sometimes want to have a little trafficlight sprint or on the German Autobahn go 100+ miles/hour

A little rich would be fine, especially with that shot of nitrous.just make sure you retard timing when you step it up to the big shot, and tune by reading the plugs.
Rich is a b---- but lean is mean.

So i'm right when i'm saying
"if I would run WOT under 11.8 i'm still running rich and I have to screw down the fuelpressure?"


when stepping up, i'll take colder plugs and adjust timing.

for na 11.8 is very rich, but since you will be using a type of forced induction id try to shoot for around 12 or a bit lower on spray.