Carb Jetting Help Wanted

[Muscleford]

I have 302 with B303 cam, shorty headers with catted H-Pipe, Edlebrock intake, 4180C Motorcraft/Holley carb.

My plugs are almost white and have been since I installed this engine. The carb has a 6.5 power valve, #70 jets at the moment (just installed them today replaced #68's), metering plate has been drilled two sizes over. Vacuum reading is steady 18, I have adjusted the idle mixture on the primary side to achieve the vacuum reading. I do not believe I have a vacuum leak, the car runs strong, idles beautifully. I do not detect any detonation.

I installed a AutoMeter wideband Air/Fuel ratio gauge and before I installed the #70 jets was giving me a 16 A/F reading. Idon't have it installed at the moment.

Why is the car running so lean? Could it be too much static timing, I believe I may be at 16 BTDC. What should I check? I have some 72 jets but gosh I am already 8 sizes over stock (stock were 622).

Ideas, thoughts suggestions???

Thanks


George

 

[PUNISHER RACING]

How are your plugs being checked? You should check them under load usually 3rd gear wide open and kill the key( just to the off pos. not to the lock pos.) drift to a stop and pull em all of em. Your idle screws should be no more thn 1 1/2 turns out and with 18* of vac. your p.v. is to small take you vac. divide in half and use corresponding powervalve. You should be using a 8.5 or so there is no reason this car should be lean if you drilled the 70's should more than work. And by the way if its not pinging white plugs are not a bad thing if it still pulls hard to 6,000.