For British drivers of carbureted, left-handed Camaros...

Vader · 2004-03-16 22:44:18

Sorry, it wouldn't fit in a PM: http://216.121.161.76/files/E4MEexplode.jpg FLOAT CHECK Remove the air cleaner and cap any vacuum lines that were disconnected; Unplug the Throttle Position Sensor and enrichment solenoid connectors; Remove the choke pull-off actuator and linkage rod (25 & 28); Remove the secondary metering rod cam follower (10) and metering rods (9); Remove the choke lever screw and lever, and the linkage rod (29, 30, & 31); Remove the air horn screws (5, 6, & 7) and the two front carburetor to intake bolts; Carefully lift the air horn (1) off the carburetor body. As you do, pivot the air horn to allow the accelerator pump linkage rod to be removed from the top lever (3, 69); Hold down the float hinge pin (57) and simultaneously hold the front end of the float (56) closed against the inlet needle and seat (55), to raise the float to its maximum position. Verify correct float level by measuring the rear edge of the float to the top of the carburetor body with no gasket in place. Gently bend the float tab to raise or lower this setting to the specification; Replace the gasket and reassemble the carburetor, being careful to properly align the metering rods, pickup tubes, and TPS actuator plunger; Reconnect the hoses and electrical connectors; TPS ADJUSTMENT Start engine and allow it to reach normal operating temperature; Set engine timing at the specified RPM; Set base idle speed with the A/C off and idle speed solenoid disconnected; Turn off the engine; Insert the probes of a digital voltmeter in terminals ?B' and ?C' on the TPS connector (center and bottom terminals). You may have to insert a paper clip or similar object into the rear of the connector to make contact; Turn on the ignition but do not start the engine. Read the voltage of the TPS. Remove the top plug (19) and adjust the TPS screw (18) to obtain a reading of 0.48VDC across the terminals. NOTE - If your meter probes are reversed, the reading will be -0.48VDC. The important factor is the number. Replace the hole plug in the adjustment screw hole when the position is set; Connect a dwell meter or oscilloscope probe to terminal ?B' on the enrichment solenoid connector; Start the engine and allow it to reach normal operating temperature. Start the engine and reset the base idle if necessary. The dwell meter reading should vary while this is occurring, or the oscilloscope square wave frequency (pulse length) should vary; Set the parking brake, block the drive wheels, and place the transmission in DRIVE for an automatic car, NEUTRAL for a manual car; The dwell meter reading should fluctuate between 10? and 50? on the 6 cylinder scale, the oscilloscope should indicate a 15-85% duty cycle. Adjust the idle air bleed valve screw (12) in 1/8th turn increments to obtain a dwell reading between 25?-35?. The optimum setting is 30? (50% duty cycle), so get as close to this as possible. Adjust the screw only a little at a time and allow the system to react between adjustments; If the desired reading is not attainable through this method, the idle mixture screws will have to be adjusted (87). This will require removal of the carburetor and cutting the throttle body away around the steel plugs. Then reinstall and adjust the idle mixture screws evenly , then adjusting the idle air bleed screw as described above to obtain the correct readings.

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03-16-2004, 04:44 PM

Vader

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For British drivers of carbureted, left-handed Camaros...

Sorry, it wouldn't fit in a PM:

FLOAT CHECK

Remove the air cleaner and cap any vacuum lines that were disconnected;
Unplug the Throttle Position Sensor and enrichment solenoid connectors;
Remove the choke pull-off actuator and linkage rod (25 & 28);
Remove the secondary metering rod cam follower (10) and metering rods (9);
Remove the choke lever screw and lever, and the linkage rod (29, 30, & 31);
Remove the air horn screws (5, 6, & 7) and the two front carburetor to intake bolts;
Carefully lift the air horn (1) off the carburetor body. As you do, pivot the air horn to allow the accelerator pump linkage rod to be removed from the top lever (3, 69);
Hold down the float hinge pin (57) and simultaneously hold the front end of the float (56) closed against the inlet needle and seat (55), to raise the float to its maximum position. Verify correct float level by measuring the rear edge of the float to the top of the carburetor body with no gasket in place. Gently bend the float tab to raise or lower this setting to the specification;
Replace the gasket and reassemble the carburetor, being careful to properly align the metering rods, pickup tubes, and TPS actuator plunger;
Reconnect the hoses and electrical connectors;

TPS ADJUSTMENT

Start engine and allow it to reach normal operating temperature;
Set engine timing at the specified RPM;
Set base idle speed with the A/C off and idle speed solenoid disconnected;
Turn off the engine;
Insert the probes of a digital voltmeter in terminals ‘B' and ‘C' on the TPS connector (center and bottom terminals). You may have to insert a paper clip or similar object into the rear of the connector to make contact;
Turn on the ignition but do not start the engine. Read the voltage of the TPS. Remove the top plug (19) and adjust the TPS screw (18) to obtain a reading of 0.48VDC across the terminals.

NOTE - If your meter probes are reversed, the reading will be -0.48VDC. The important factor is the number.
Replace the hole plug in the adjustment screw hole when the position is set;
Connect a dwell meter or oscilloscope probe to terminal ‘B' on the enrichment solenoid connector;
Start the engine and allow it to reach normal operating temperature. Start the engine and reset the base idle if necessary. The dwell meter reading should vary while this is occurring, or the oscilloscope square wave frequency (pulse length) should vary;
Set the parking brake, block the drive wheels, and place the transmission in DRIVE for an automatic car, NEUTRAL for a manual car;
The dwell meter reading should fluctuate between 10° and 50° on the 6 cylinder scale, the oscilloscope should indicate a 15-85% duty cycle. Adjust the idle air bleed valve screw (12) in 1/8th turn increments to obtain a dwell reading between 25°-35°. The optimum setting is 30° (50% duty cycle), so get as close to this as possible. Adjust the screw only a little at a time and allow the system to react between adjustments;
If the desired reading is not attainable through this method, the idle mixture screws will have to be adjusted (87). This will require removal of the carburetor and cutting the throttle body away around the steel plugs. Then reinstall and adjust the idle mixture screws evenly , then adjusting the idle air bleed screw as described above to obtain the correct readings.

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03-16-2004, 04:56 PM

si_camaro

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Car: 85 Z28

Engine: LG4 modified

Transmission: 700R4

Thank you very much, J.

Duly saved!

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03-16-2004, 05:05 PM

Vader

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And the elusive secondary metering rod & hanger data:

EDIT: You might also like the rod length information:

Tip Length Legend:

LL: Extra long power tips supply richest mixture starting at 60° of air valve opening.
Never use in performance applications using greater than 70° air valve opening.
L: Power tip starts at 70° air valve opening.
Tip considered to begin at that part of the rod that is within .003" of rod's minimum diameter
M: Power tip starts at 80° air valve opening.
Tip considered to begin at that part of the rod that is within .003" of rod's minimum diameter
M/S: Power tip starts at 80° air valve opening.
Tip considered to begin at that part of the rod that is within .005" of rod's minimum diameter.
S: Power tip starts at 90° air valve opening.

Last edited by Vader; 03-16-2004 at 05:23 PM.

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03-16-2004, 05:16 PM

Vader

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"D" hangers and "DR" metering rods are common selections for performance improvements. "H" or "I" hangers are reasonable choices for a 305, along with the appropriate metering rods.

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