Avette4me

Just bought a pair of GM bow tie valve covers and the EGR valve appears to be in the way. I never really liked it up there any way (too much extra stuff) and would like to take it off.

What will happen if I remove it and cover the hole, plug the vacuum line, etc..

Any help is appreciated.

TedH

The EGR (as your probably know) mixes exhaust gases with the fresh air/fuel charge. Blocking the EGR hole (I bought this plate from a forum member as my EGR had been literally welded shut on the underside and was a 'dummy' EGR for inspections only) may cause the engine to run richer as the a/f charge will now have less waste gases mixing with it. As a result, carb jetting/tuning may be required. More or less depending on the valving of your EGR. As I mentioned, with a 'dummy' EGR, impact of installing a block-off plate on my car was 0%. My understanding is that the EGR closes under WOT so the primary/main jet/metering should be the only adjustments. Check with Lars, he probably has better intel on the impacts and may even be able to corelate your EGR (using number stamped on the top of it) to recommended tuning adjustments to compensate for its removal. IMHO, this would be valuable tuning info for those of us considering EGR removal.

Avette4me

Thanks Ted. I figured that air mixture would be some concern, but wasn't sure of farther reaching impacts.

I appreciate your help.

Lonny :cheers:

wcsinx

Wouldn't it cause you to run slightly leaner as you're now taking in more air (i.e. less exhaust) than your carb was tuned to?

WydGlydJim

The effect of EGR is to lean out the mixture under certain conditions, by adding exhaust gas back into the intake system. This lowers cylinder head temps under these conditions, which lowers emissions. It is correct, that it is used only in part throttle applications. The only caution I would say, ( in deleting ) is that in some cases if the head temps are right on the edge, it can cause pinging under light acceleration, because exhaust gases are not being introduced to cool down the head, and that would be hard to get rid of. It's kind of a try and see thing. The newer the car, the more it would need to be the way it was engineered.
:cheers:

BSeery

If for some reason you still wanted to run the EGR, I think they make spacers / adapters to move it out of the way.

WydGlydJim

Oh, BTW; it is real easy to imitate blocked off operation!. Just disable the vacuum source (unplug and cap the line). The valve rests in the blocked off position. If you see no drivability probs in the disabled operation, i.e. pinging, stumble, etc., you're good to go!
:cheers:
Just running a few more emissions, but how many Vette owners care about that!
:D

Glutamine83

is there any HP increase when you block off the EGR?

Avette4me

Thanks gentlemen! You've helped me decide/confirm.

I though about the spacer thing, but kinda want to clean it up under there anyway, smog stuff in a box, not under the hood. :D

I'll be removing it and capping/plugging tonight. If anything really wierd happens, I'll let ya know.

Thanks Again! :cheers: :smash:

Jvette73

if it was functioning before you remove it, my guess is the only thing you'll notice is your car running better with it gone