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> A/F readings, What do the experts think?
Black22
post Aug 19 2012, 04:47 PM
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Hey all,

I've got a 1911cc motor with about 250 miles on it. KB pistons, stock cam and L-jet, with 1.8l heads modified to 2L valve sizes. Compression is 8.5:1. Running Brad Penn 20/50.

Car was recently running way rich and got VERY poor gas mileage. I hooked up with Joe Sharp, (thanks again Joe!) and he let me use his LM-1. I tried to dial my L-jet in and got pretty close. I've since purchased and installed an Innovate MTX-L AFR kit. Gauge works great! Here is my readings as of now and after MUCH tweaking this is my dilemma.

AFR stats:
Idle= 12.7
WOT= 9.7-10.2 (it will hit these readings regardless of RPM)
Decel= 14.8-15.9

Timing is set @ 7.5* @ ~900rpm with vacuum ports disconnected and plugged.

WOT seem rich still, but now my motor runs hotter. I know I'm leaning the motor out and should expect higher oil temps but I was running about 190-200 and now I'm running 210-220. I'm also running an external 72 plate oil cooler w/fan!

I've adjusted the timing to experiment, and had it at 9.5* adv. and it ran cooler at idle but the temp went back up while driving.

It seems I have some more adjustments to get it even leaner, but that's just going to raise the temps right? (IMG:style_emoticons/default/confused24.gif)

What do you guys think and what should I do (if anything) next?
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ChrisFoley
post Aug 19 2012, 05:21 PM
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You need to adjust the wiper inside the AFM to lean it out across the entire rev range.
Someone just posted a link in another thread to a very good explanation of how to adjust L-Jet.
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Black22
post Aug 19 2012, 05:28 PM
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QUOTE(Racer Chris @ Aug 19 2012, 04:21 PM) *

You need to adjust the wiper inside the AFM to lean it out across the entire rev range.
Someone just posted a link in another thread to a very good explanation of how to adjust L-Jet.


I think you are referring to me. I posted that link to the article. I'm doing all adjustments based on the readings and that article.

What do you think about the temps? I don't have a CHT gauge but I can feel the heat coming off the engine and it seems WAY hotter.
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