EGR Delete - Will I benefit?

[Nathaniel2g]

Hey guys,

Just looking for some information and advice - I have a 1997 GMC K1500 with a 5.7l Vortec and 4l60E. Currently have a Blackbear performance tune on the way, cold air intake and 2.5" straight pipe. My truck has 480k KM on it.

Very shortly (spring or sooner), I plan on doing some motor work. I've already swapped in a newer 5.7l Vortec with only 160k km and it is clean. The truck is noticeably more powerful and runs a hell of a lot better. I have long tube headers on order and plan on putting the largest cam possible with stock Vortec head clearances and possibly boring .030 over.

My question: I've seen and watched EGR deletes done on these old trucks. Some people claim you will have more power and slightly better fuel economy by deleting the truck, but I don't see that being possible. The EGR is recycling unburned gas, theoretically making it have better MPG than without. Will I actually gain anything from deleting the EGR? I would guess that performance gains would only be 3 - 5HP, but I don't know much.

 

[Christian Steffen]

EGR only opens at part throttle cruise, so no you won't see any performance difference. It will keep your intake cleaner though. I've heard rumors that your mileage will go down a bit with it deleted, but I have no first hand experience there so hopefully someone else will chime in.

 

[someotherguy]

You misunderstand the EGR's function or it has been misrepresented to you.

The EGR puts exhaust gas back into the intake stream. This isn't to burn "unburned gas" - the exhaust gas is mostly inert. The idea is that this inert gas helps cool the combustion chamber, preventing detonation (spark knock/ping.) It allows for a more aggressive timing curve on the specified grade of fuel (regular, in your truck's example.)

If you delete it, your tune will need to compensate for that in terms of the timing curve. It's something any good tuner already understands. If you delete it and don't make any change in the tune, you will have pinging, which will eventually destroy the engine. It hammers the **** out of the bearings and can damage pistons.

Richard

 

[Nathaniel2g]

You misunderstand the EGR's function or it has been misrepresented to you.

The EGR puts exhaust gas back into the intake stream. This isn't to burn "unburned gas" - the exhaust gas is mostly inert. The idea is that this inert gas helps cool the combustion chamber, preventing detonation (spark knock/ping.) It allows for a more aggressive timing curve on the specified grade of fuel (regular, in your truck's example.)

If you delete it, your tune will need to compensate for that in terms of the timing curve. It's something any good tuner already understands. If you delete it and don't make any change in the tune, you will have pinging, which will eventually destroy the engine. It hammers the **** out of the bearings and can damage pistons.

Richard

It was definitely misrepresented to me. So my question still stands - with an EGR delete and proper tune to compensate, am I going to see an increase in power and/or fuel economy? I've already ordered a Blackbear tune that I've requested be tuned for 91 octane, so I'd possibly like to add the EGR delete to the tune before they ship it.

Edit: Also, is there a write up on a proper EGR delete around?

 

[someotherguy]

Usually more power and fuel economy are mutually exclusive. Which do you want? Your tune will have different directions based on your desired outcome. It's old-school non-thinking of "removing emissions equipment = more power"; the EGR is not robbing you of any power. To stretch the thinking a little bit, it actually allows for more power to be made in the stock setup than would be allowable without it.

If you live anywhere that has emissions inspections you will fail immediately on visual inspection.

Physically deleting it is fairly easy; you fashion a block-off plate for its spot on the intake manifold, and plug each end where the EGR tube was.

Richard

 

[Biggershaft96]

the only difference youll see is the difference from the tune. Egr deletes are pretty useless on a stock vehicle other than the fact that your intake will stay cleaner, but then it still gets dirty from the pcv system. IMO have bb shut it off then physically delete it if or when you get a set of headers.

 

[arrg]

Unless your long tubes have a hook up for the EGR tube, you'll be deleting it when you install those regardless of whether or not you physically remove the valve. It won't have a source of exhaust gas to recirculate.

 

[Supercharged111]

EGR reduces NOx, I believe that's its primary purpose. To make the most out of it, fuel is reduced to match the actual oxygen content and timing is advanced to match the decreased cylinder pressure. I saw no difference in performance or mpg when I deleted mine. Deleting in the tune is as simple as turning EGR off, no need to redo any timing. EGR has its own timing adder table that is no longer used once EGR is turned off.

 

[Spookers]

I agree with supercharged111, literally as simple as un-ticking a box in the tune, it also makes it easier to tune for the cam, long tubes, intake etc. without egr. I would also suggest running the pcv system to a catch can, you can still run vacuum to it if your worried about it, or don't use vacuum and toss the pcv valve (its a restriction unless under vacuum) the benefit will be increased vacuum which increases fuel economy, intake will stay cleaner, plus a little less hot air in the intake

 

[big_mike]

EGR is a crap emissions component. There are benefits to removing it, don't really care what some argue for keeping it. There is no denying fresh clean air is better then recirculated heated air. The theory it could "cool" the chamber goes against basic logic.

Remove it and have it deleted from the pcm, simple as that. Have done it myself on other vehicles and known many more who have done it with ZERO negative effects.