My experience is just the opposite. After driving my '88 201/2.6 for a half hour and letting it idle for ten to fifteen minutes while I measured the O2 sensor duty cycle I measured the exhaust manifold with an IR gun at only 475F and the converter inlet was only 220. Coolant temperature was about 90C.
Find someone with an IR gun and take some measurements. Also, check your initial timing and see if it's to spec. Mine was right on the 9 degrees spec, but I want to retard it to increase the EGT so I can pass emission testing by more than the skin of my teeth.
Less than 500 degree manifold temperature with only 9 degrees idle timing was a real suprise. The 103 combustion chamber must have faster flame propagation speed than I ever imagined; most engines with only 9 degrees idle timing will show manifold temps a lot higher because so little timing is much less than optimum, and retarding from optimum increases EGT. You have to go back to pre-emission controlled engines with full vacuum advance at idle and 20-30 degrees total idle timing to find such low manifold temps.
Last edited by Duke2.6; 05-20-2003 at 09:50 PM.