231 N/A rebuild ???????????

[Buick in Olds]

231 N/A rebuild Questions
Looking for some help from those who have done the upgrade to the 4.1L manifold and 4 barrel carb.

Finally have the motor complete and installed in the car tonight, just about bolted in! My upgrades include mild porting and polishing of heads and intake. Installing the 4.1L manifold and rebuilt Quadrajet, installed a new cam (in a GM "Target" crate motor), running hotter HEI ignition, CAT-Back dual exhaust and installed a 3.42 gear w/posi. Have also changed changed rear springs and boxed the rear control arms.

My questions? We plan on NOT putting the air pump back on car and plugging tube to CAT. Also thinking of running EGR straight and not using the solenoids on the passenger valve cover all while using the ECM. Car is a 1984 version G-Body! Whew! thanks in advance for any and all help!

 

[gofstbuick]

The AIR system helps the cat light off. I suspect the EGR solenoid has manifold vacumm to it. At a specified temp, speed and gear, it makes the connection to the solenoid to allow manifold vacuum to the EGR valve. If you bypass the solenoid, the EGR will open at idle, causing a major vacuum leak and / or stumble. If the EGR is allowed to work during engine warm up, the cooling effect (created by the EGR valve being open) on the cold cylinder walls may cause the fuel to change from a vapor to a partial liquid. The effect will be a stumble. Here is a Detroit Auto maker deduction. In 1972 EGR began appearing on Mopars, GM and Fords. Initially temp sensors were not used and many compaints were generated for stumbling problems (while the engine was cold). The complaint problem must have been severe, because all domestic manufacturers incorporated some type of temp sensors (to control EGR function) mid year! Now computers control EGR function and rely on coolant temp, speed, gear selection, throttle position and sometimes even exhaust back-pressure. IMHO, I would let the computer continue to control EGR function.