I have a 400 that the EGR valve is broken on. If I take it off and put a plate over the hole, Will it cause any problems with the way it runs, or drives. Thanks RUSTY

 

You might lose 1 mpg. I swapped the EGR spacer plate out on a 300 6, and replaced it with a pre-EGR spacer plate under the 1bbl carb. Runs fine with no problems.

EDIT: I should mention I used the non EGR spacer and carb (early 70's) from the same engine, along with efi headers ('89), so the "system as a whole" became non EGR. ('86 300 6 in '79 Bronco)

 

Where are you going to find a block off plate?

1971/72 400: There was no EGR valve, so the carb spacer plate had no place to mount it.

EGR valves introduced 1973, every 1973/82 400 had one.

 

The exhaust gas introduced into the intake charge by the EGR system is an inert gas and serves to cool the combustion chamber and allow the use of a leaner air/fuel ratio without pinging. When the EGR system is disabled, it is common to run into trouble with severe pinging. The solution is to either pull out timing until it quits or to install bigger jets in the carburetor to get enough fuel in there to cool the combustion chamber and make it stop. The former solution usually results in a severe loss of power and the latter will maintain your normal power level, but fuel economy will suffer.

 

Thanks fellas; I thing I'll just replace it. RUSTY