Author Topic: Low 10s AFRs on slight throttle  (Read 2398 times)


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Low 10s AFRs on slight throttle
« on: 17:35, Sat 13 July 2013 »
Hello again people. I had some issues with my 5 before. Managed to solve everything but still got a major one.
On the AEM  gauge, on slight throttle shows low 10s. Ac jet is drilled at 1.1 to help solve the issue but nothing (previously at 0.9).
main jet is standard 1.2.  On the enrichment circuit, 1st removable jet is 1 mm and the second stage is drilled to 1.2 to help the on wot fueling.
 At 16 psi with a T25 turbo i get 11.5 afrs (way too rich though), on slight throttle-cruise i have constant low 10s (10-10.5)...
Is there a possibility the fuel regulator is faulty? If for some reason it is, and allows more fuel pressure, is it possible for the above effects to produce?
Carb is serviced and cleaned. I'm busting my head to fix this cause from one hand the fuel consumption is extremely bad, plus the constant so rich mixture will fook up the engine for sure.


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Re: Low 10s AFRs on slight throttle
« Reply #1 on: 21:43, Tue 24 December 2013 »
I had the same issue as this, but I don't think I know what sorted it? I couldn't figure it out so decided to rebuild the Carb, but I took the time to get all the mating faces nice and flat using 600 grit wet & dry on an engineers flat surface (I used the underside of a Vee Block).

I also replaced my ignition module (AEI) with a Megasquirt controlling a Ford wasted spark system (EDIS4).

So it was either the rebuild or the new ignition?
Love 5\'s so much I took mine to Oz to scare some V8s