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VEMS Community Forum

Technical => Fuel Injection => Topic started by: Siena on October 04, 2009, 10:06:56 PM

Title: AFR At Part Throttle / WOT?
Post by: Siena on October 04, 2009, 10:06:56 PM
Hi Guys,

Fitted my new 350cc injectors today, and set the new values. Idle AFR is between 14.5 and 15.2, and she revs cleanly.

My question is, what is the ideal AFR at part throttle and WOT? I haven't driven her hard yet, just wanted to know what the approx. AFR readings I should be seeing at higher RPM.

Thanks.
Title: Re: AFR At Part Throttle / WOT?
Post by: gunni on October 04, 2009, 10:39:53 PM
What engine do you have?

I´d say stick to Lambda 1 below 80kpa.
Lambda 0.9 from 80-100kpa
Lambda 0.80 above that for starters
Title: Re: AFR At Part Throttle / WOT?
Post by: Siena on October 04, 2009, 10:47:00 PM
Sorry Gunni, Audi ABZ 4,2L V8.

I'm more used to using the VEMS AFR gauge though.

Would you say between 11.5 and 13:1 is a safe ratio at WOT?
Title: Re: AFR At Part Throttle / WOT?
Post by: Siena on October 04, 2009, 10:53:52 PM
Doh! Silly me, I'm not concentrating.

13:1 at WOT is way too lean.
Title: Re: AFR At Part Throttle / WOT?
Post by: gunni on October 04, 2009, 11:35:23 PM
Why is that to lean?
That´s what most NA engines like.
Title: Re: AFR At Part Throttle / WOT?
Post by: Siena on October 04, 2009, 11:41:30 PM
I thought at WOT it would be too lean?

I'll set it for that value tomorrow, and try it out. It'll also keep the big V8's thirst to a minimum too!
Title: Re: AFR At Part Throttle / WOT?
Post by: dnb on October 11, 2009, 07:12:43 AM
13:1 is good for NA engines at WOT.  You could even go a little leaner if it doesn't compromise your timing curve.  (Save testing this for the dyno though!!!)
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