Reading spark plugs

Your head is in the right place -- look at the idle mixture, that's where most of your driving is done.  But before you go messing with jets, have you adjusted your idle mixture???

And before you mess with your idle mixture, have you perfectly balanced the carbs for identical idle vacuum?

You probably have already done all the fundamental requisites first, because swapping jets around is the very last thing you should think of considering.

I owned a 1969 911E Targa and built a 2.4 engine for it using the E cams.I removed the Mechanical fuel injection and installed dual three barrels .  When I got it done it ran very rich ( stock jetting) with the carbs, on mine it was not the carbs but the ignition system that was weak. I replaced the ignition system with a MSD  6AL box and coil, used a Pertronix setup in the distributor to eliminate the points and never had another problem . I did not have an A/F guage but the tail pipe stayed clean. Another benifit was the elimination of the factory preset rev limiter, I ran the car up to 146 MPH on an empty hwy until I got nervous,hahahha , no Autobahn in North Carolina.  Mike McCarthy

Mike, why did you exchange the fuel injection for carbs? More power? And....would you consider selling me the FE setup for my '72?

I remember now that using the stock recommended Weber set up for the other engine (911T) I had in the car also made it run rich.  I had to go down a size or two in the jetting.  At that time I was still using the stock ignition system.  Now the new ignition system should be up to the task as I am running an Electromotive crank fired system.  I'm hooking up the AF meter today so will try and dial it in over the weekend, weather permitting.  Thanks for the suggestions.

Hey Berry,

          My mechanical injection was set up for the original 2.0 engine and it did not run well to begin with . I traded my 2.0 for a 2.4 engine ( he didn't know the crank was the same as a 2.7)that needed rebuilding but was complete. I rebuilt an engine for a doctor who specified new clinders on his 2.2 T and his old ones which were perfect he gave to me. I was able to keep the valvetrain from the 2.0 /cam and everything else but gave the Inj to him which he needed to complete his 911S. I still have a set of dual three barrel Webers with manifolds and factory air cleaners, everything but linkage I would sell.

         I was lucky that I drag race VW's as the MSD bits were spares. They did not make a Pertronix setup for my distributor but I was able to use parts from my 4 cylinder kit and an available 6 cyl  kit to come up with my setup for the distributor.

Good luck with your tuning , cheers, Mike McCarthy