AFR Ratio

ash · December 11, 2008, 09:54:24 AM

Can someone please? Just put my mind at rest on my AFR gauge reading. I have just bought a new RX7 with loads of gauges including a GReddy AFR guage. When cruising its reads 8.0, and when lifting off it reads the other endof the scale 16.0 i think.

So is 8.0 Rich i.e. 8 Air : 1 Fuel

and

16.0 i.e. 16 Air : 1 Fuel

So is this ok?

P.s - its a single turbo.

Also heard that these non - wideband gauges are useless!! :Giggle

BlitzBoy · December 11, 2008, 09:57:29 AM

ahh its a narrowband, next to useless, just tells if you are running on Rich scale or Lean, just looks pretty

hairyhoover · December 11, 2008, 10:02:26 AM

dont narrow band whizz back and forth when cruising and idling?

ash · December 11, 2008, 10:04:06 AM

Yeah it really is a bit distracting when your not sure what they should be doing. So should i be worried about the readings or just be happy with my portable Christmas Tree?

BlitzBoy · December 11, 2008, 10:27:51 AM

Just be happy with your new Christmas tree lol

ash · December 11, 2008, 10:33:45 AM

Nice One! Cheers Blitz!

Prof · December 11, 2008, 11:14:29 AM

or buy an Innovate LC-1 Wideband controller and use one of it\'s analog outputs to drive the \'useless\' gauge - and make it a little more useful. :Thumbs-up

ash · December 11, 2008, 11:39:51 AM

Just had a quick look at the LC-1 controller..hmm bit expensive are\'nt they!

hairyhoover · December 11, 2008, 11:59:04 AM

wideband arnt cheap but worth the cash! although it does make you a bit paranoid!

Will66 · December 11, 2008, 12:33:59 PM

Am I right in saying that 12:1 is pretty much the ideal AFR?

BlitzBoy · December 11, 2008, 12:37:35 PM

depends on boost pressure, low boost up to 12psi 12:1 is fine, the higher the boost you go the richer you should be to aid chargecooling and stop det.
On NA probably 13:1 at WOT but tuners have there own numbers they use for best power and the type of petrol being used

Will66 · December 11, 2008, 12:40:18 PM

Aha, interesting! I think I can get my CampII to show AFR, I might have a look at what mine does!

BlitzBoy · December 11, 2008, 12:45:56 PM

yep you will need to get a Bosch (or similar) wideband sensor fitted before the CAT pipe to get a true reading then hook it up to your camp unit

nikp · December 11, 2008, 12:50:08 PM

Aren\'t bosch the only suppliers of the sensor? I am not aware of anyone else making them - but i may be wrong!

m1tch · December 11, 2008, 06:13:32 PM

You can either spend a bit more cash on a wideband sensor and get a good reading, or not and the engine run lean and cause you to need a rebuild lol I know what I would wanna choose