EGR - necessary?

[Kurt Reiter]

my 350 sb has a performer edelbrock intake manifold without a connection for an egr valve. Do I need one, and if not, how will it affect my vacuum hoses? thanks in advance-

Kurt

[Joe L.]

Re: EGR - necessary?

Kurt----

By 1979 the emissions controls systems on Corvettes (and other cars, for that matter) were very integrated. If you remove one portion of the system, it affects others. Removing one part of the system can actually have a negative effect on overall vehicle performance, too. In any event, with the EGR valve removed, the only effect on the rest of the vacuum hoses is that the line which formerly went to the EGR will need to be plugged.

Also, with the EGR removed the vehicle is illegal under federal law and the laws of most states. So, if you require a smog inspection on a periodic basis or at change-of-ownership, the car will usually be an "instant fail".

[Kurt Reiter]

Re: EGR - necessary?

Thanks, Joe. I can't tell you how invaluable your information is. As you can tell, I'm a first time rebuilder, and although I am having a great time, it really helps to have someone to get me through. Thanks!

Kurt

[Clem Z.]

Re: EGR - necessary?

a lot of engines will "ping" without a operating EGR because the exhaust gas believe it or not cools the combustion chamber preventing "pinging"

[Duke W.]

Re: EGR - necessary?

EGR reduces peak combustion temperature (for less NOx formation in the flame front) and slows flame propagation speed. The carburetor is calibrated specifically for EGR so disabling the EGR might require recalibration for optimum part throttle driveability. The timing curve is also affected. Because EGR slows flame prpagation speed, less vacuum advance may be advisable without EGR.

EGR has no effect on the WOT torque curve because the valve is only open at part throttle.

Duke

[Clem Z.]

i should have posted "part throttle pinging" *NM*