QJet APT question
Le Mans Master
Joined: Jul 2006
Posts: 8,117
Likes: 104
From: charlotte north carolina
there are no mechanical connections between the primary rods and the primary throttle butterflys. the apt is controlled by the engine vacuum. if calibrated properly, the 'proper' apt spring will lift the primary rods out of the jets in exactly the 'correct' amount so that the 'corrrect' taper allows 'proper' amount of fuel to mix with the 'proper' amount of air that is entering the engine. what's 'proper'-that's the $64,000 question! read lars' papers and you'll start to get a hint. i've read them several times, and i'm still confused as all hell, but the cloud is slowly lifting.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
Lars
Thread Starter
Racer
Joined: Feb 2013
Posts: 386
Likes: 3
From: Clifton Virginia
Thank you for the info. What is the factory setting for APT screw? 3 turns out? I checked mine and it's about 4 turns out from seated.
