|08-18-2006 02:45 AM|
There's some info on power piston adjustment at the bottom of this document.
|08-17-2006 09:24 PM|
the power piston stop or APT screw is set at the factory to give the engine the correct cruise a/f mixture. a good place to start is 3 1/2 turns from the bottom, then use it to adjust the cruise mixture. the way we set the cruise mixture is with a exhaust gas analyzer, the CO reading taken in front of any catalitic convertor and with any smog pump disabled is to target a CO reading of 0.75 -1.25% CO. (any smog shop should be able to give you the readings for just a few$),you could also use a air/fuel meter such as the Innovate Motorsports LM-1 and then target a air/fuel mixture reading in the 14.2-14.5 to 1 range. i know of no easy way to do the APT screw other than those methods or trial and error spark plug readings.
henry @ oles carb
|08-17-2006 09:08 PM|
|08-17-2006 08:44 PM|
I wish my uncle, or grandpa were around right now... they can tune any hesitation, any problem, out of a qjet.
Unfortunatley, I was raised in the fuel injection for the masses age, so this is unknown country for me. From experience and most service manuals, for tuning screws and otherwise it's 1.5 turns back of the seat/bottom. Hope my efforts help!
|08-17-2006 07:54 PM|
Rochester Quadrajet! help
I am in the process of rebuilding my rochester quadrajet carb m4me or such... anyhow i took out my power piston stop and spring, and have no idea of the general ammount of turns it should be out.. anyone ever do this? or know a good setting that is emissions friendly? ive been searching the internet for over a hour and cannot find a base setting.. so im here for all the carb guru's help.. thanks in advance