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Weber Jet Help


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Need some help guys. I believe my stock L20b with a Weber 32/36 DGV is running too lean and this has been the root cause of my elevated cruising temperatures. I installed a AEM wide band O2 a while back and at idle it hovers around 12 ish. If I'm just crusing down the freeway it seems to be 14.5 +- . Any acceleration or increase of load (a hill) to the engine causes the A/F mixture to go off scale lean. It runs fairly well but I'm concerned about the effect of running too lean for too long.


Plugs are whitish ... kinda/sorta spotty light tan if you look at them in just the right light.


Here are the jets as installed -


Primary Main 140 Air Corrector 135 Idle 55

Secondary Main 165 Air Corrector 160 Idle 50


Timing 12 degrees with 35 degrees of advance at 3000rpm


Any help would be greatly appreciated.

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Mine does the same thing... It leans out on hills and romps...


I think mine right now is


160 air primary 140 air secondary

145 gas primary 160 gas secondary...


at 6 deg I think?


still have not driven it yet. I hope the more gas on the secondary makes it behave better.


I am starting to think that maybe... MAYBE! The fuel pump is not providing enough fuel during the romps and on the hills...

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Good article called 'Weber Tuning Guide' in General Technical, good reading.. Also 'olddatsuns.com is good place for info..


To me I'd say that the Primary is too lean. The more throttle used on hills = more load on engine = leaner condition.. as far as the secondary side, primary first..

14.5 across the board would be good, but that's my opinion (backyard mechanic school...)


Try like: Idle: 55-60 (Depending on mix screw turns out, shooting for 1.5-2 turns at smoothest/highest idle)

Main: 145-150

Air correctors: are for high end flow(4,000-6,000+ RPM) once the idle and main jet are set for smooth transition and mid range power, then play with this so that the power doesn't fall off( Fall off: the power is good and building through the RPM, then it falls on its face = too lean)


Any 'ping'.. lean detonation over time no good either... pinging on hills/under load is tell-tail of lean also

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