EGR MOD

[jweir22]

Anybody heard of making the hole back into your upper intake from your EGR Valve 75% smaller allowing less hot exhaust fumes back in to your Upper intake thus getting rid of some hesitation and getting some top end back?Just Saw it on another site for a 4.3 and they said it worked great just wondering if it would work for our 60 degree engines?

[Anonymous]

Sounds bogus to me because the EGR is ONLY on during cruise and light throttle. At WOT, the EGR is closed.

[korbendallas68]

Oh God! If they make another bogus eBay mod...

[geoffinbc]

Yea its a busshit mod and can lead to bad gas milage, check engine lights, pinging and in severe cases detonation. Some people claim to gain low end torque but I think any power they are feeling is purley in their heads (mental horsepower). Because as already stated EGR is only active under light throttle crusing.
Here is a good read http://www.asashop.org/autoinc/nov97/gas.htm

[jweir22]

OKay all good points but they say you can make the hole smaller and still the light will not come on.Anyway don't you guys think the less of the exhaust gas going into you combustion chamber is better.It does not Detonate the second time so it just takes up cold air space and i hate the black tar it leaves in my shiny polished intakes,i just find it hard to believe i have this big K&N filter to filter the air into the intake and then they go ahead and bypass the filter and throw junky exhaust gas thru.Heres the thread if someone wants to look at it. http://www.s10planet.com/tech_egr.htm http://www.s10planet.com/tech_older_egr.htm

[korbendallas68]

Its better in some ways and in someways not... I don't have the EGR even on my manifold, and the car runs flawlessly (well no, but it not because of the EGR). The exhaust gas is supossed to cool your cylinder walls. I agree with you on the black sludge in the plenum, mine is nice and clean still.

[SappySE107]

Fuel is based off EGR%, which means that keeping the EGR on and then modifying its flow will throw the fuel tables off. The computer will expect more exhaust gas, which means it needs less fuel. I suspect it will run slightly lean with this mod, until the computer compensates for it. Over some time, the computer will have adjusted for the tables being wrong and all will return to normal. I don't see how they notice better low end unless its part throttle. Its not going to increase HP at all, but give a feeling of better power at part throttle. Essentially, you won't need as much throttle for the same effect...but peak power at any RPM won't have changed one bit. I don't see a dyno sheet from them. I cant even find that part in their store.

The carbon build up is the only reason I turned my EGR off. The engine heats up faster (that person saying their engine runs cooler has problems, it makes no sense on so many levels), and I noticed NO performance increase at all. Maybe on a dyno I would see less losses over time...or you can just run top engine cleaner every once in a while to remove the deposits. The combustion chamber is gonna have deposits no matter what you do to the EGR, which matters much more than intake manifolds. We don't have fuel through the intake manifolds, so the sludge won't effect them at all. The intake valve however, you will get a buildup on the backside where as I don't have any now.

That mod..whatever. Its still letting EGR gas through, so whats the real point? It doesn't get the intake valve benefit cause the exhaust exists in the intake anyway. Just delays the results.

[korbendallas68]

If the EGR somewhat controls fuel, could that cause my car to not be running correctly?

[SappySE107]

if its not turned off in the computer...maybe. If it is giving you a code for the EGR not being there, then it will probably also use the EGR 0% fuel constant. The fuel constant itself is based off EGR. Every other variable is part of the math formula based off it.

[korbendallas68]

Well I don't have a code reader, but I am pretty sure that the EGR code does come on, because after going above 60 mph (then cruising or any hard accelerating), the SES light comes on.