A/F at Cruising

[elton]

Hey guys,

Am in Malaysia here and would like to know if we're able to cruise at a 15.0AFR.
Current setup was tuned at 11.5AFR on boost and 14.7AFR on cruising.

I somehow notice an increase in fuel consumption after the tune when i put in a rrfpr and walbro 255lph. Also have a decat and FMIC. That's the reason I'm asking about the 15.5afr... wonder if colder plugs would help as I'm running on platinums 6-7 grade which i cant remember

Opinions anyone>?

 

[HYBRID]

ideal cruising AF is between 14.7 & 15.0 .. dont go leaner on cruise thats what the 4e likes.

kon

 

[JasonGlanza]

x2

 

[elton]

anyone tried 16.0?

Btw, how much do you guys normally tune on boost? 11.5 or 12?

 

[sx_turbo]

14.7 on cruise, leaner and it'll go bang.

between 12.5 and 11.5 on boost

 

[elton]

would i be able to squeeze more power if i go 12-12.5 from the current 11.5?

 

[sx_turbo]

it is possible.

normal rule of thumb though is to get the a/f's at there leanest till the stop making more power.

then make it richer until the max power starts to drop off,, then the max safe power is between the 2

 

[elton]

thanks mate!

The reason i was asking is because we Malaysian are paying shit for fuel here therefore the question about running a 16.0 AFR

 

[pig666eon]

thanks mate!

The reason i was asking is because we Malaysian are paying shit for fuel here therefore the question about running a 16.0 AFR

i think i would rather pay it at the pumps than in a garage man

 

[JasonGlanza]

low 11s on boost will be gd and at cruising as said above 14.7 low 15s gd

 

[dac69er]

14.7 on cruise, leaner and it'll go bang.

thats a bit extreme!!!!! you can go leaner than that under cruising conditions without there being a problem, as long as you dont go too mad.

 

[JasonGlanza]

thats a bit extreme!!!!! you can go leaner than that under cruising conditions without there being a problem, as long as you dont go too mad.

exactly dac69er

 

[HYBRID]

thats a bit extreme!!!!! you can go leaner than that under cruising conditions without there being a problem, as long as you dont go too mad.

ditto... the chance of a low compression engine going bang whilst cruising due to lean af's is well.. difficult, unless its so lean it starts to pink and judder...

as for tuning on boost, af is very relative to many other factors.. ie how much boost ur running, if ur running alot of timing, depending on what type of fuel ur using.. etc , these
all add up to the equation of where u want ur af to be... u can find a good balance of "power Vs safe" af ratios... no to engines respond the same to tuning, some engines may prefare (ie give better results)
with a richer condition... and vice-versa .. Thats why its very important to feel the car ur tuning, not just tune it based on common practice

Kon

 

[elton]

So conclusion a 15afr would be acceptable?

Btw,

Am running on 5efe pistons on a 4e engine, shaved flat .

 

[12345678]

yes, 15 will be fine, its the on boost afr's that will destroy an engine quickly