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jackson
08-02-2008, 02:58 PM
hello all ! i'm new here , i'm looking for someone ( or business ) in the cleveland area to tune my 304 in my jeep . i'm .040 over on the pistons and have the edelbrock performer cam, intake , and 500 cfm carb , also have a d.u.i. hei distributer . she runs great ( as far as i know ) but i was told, if i weld in an oxygen sensor bung behind the headers , there is some high tech ways to get me dialed in right where she needs to be... any thoughts or recommendations would be greatly appreciated !

AMX69PHATTY
08-04-2008, 11:26 AM
Best power is achieved with optimum ignition advance curve and fuel air mixture. Adding a wide band O2 Sensor and a Rich / Lean indicator will allow fine tuning the carb and jetting for best mixture, for power about 12:1 air:fuel, and for economy about 15:1 air:fuel, throughout the rpm range. Edelbrock, Holley, and others offer Rich / Lean indicators that work with O2 sensors. They're stand alone "gauges" and do not require a computer. Re-curving the distributor advance curve is another way to help get peak performance. Unable to offer any info on shops in the Cleveland area.

jackson
08-05-2008, 07:37 PM
thank you ..... it will still help for when i do find a shop .

AMX69PHATTY
08-05-2008, 10:42 PM
"Hot" Distributor Timing Advance Curve Set-Up

Total Potential Full Advance
~14 deg Initial Advance set at idle with NO Mechanical Adv & NO Vacuum Adv
~24 deg Total Max Mechanical Adv all in by 2500-3000 RPM's
~38 deg Sub-Total Initial and Full Mechanical Advance
~16 deg Total Max Vacuum Advance with a Can that is all in 2" lower than idle vacuum
~54 deg Total Max Potential Full Advance @ ~3k rpms & ~15" of vacuum

Advance at Idle
~14 deg Initial Advance
~16 deg Vacuum Advance attached to Manifold Vacuum
~30 deg Total Advance at Idle with NO Mechanical Adv coming in at Idle

Be careful of Detonation.
If it pings, or if small black specs appear on the plug's porcelain,
reduce the Initial Advance, or the rate and/or amount of Mechanical Advance.

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