Official 420A EGR Block-off Disscussion 2007

[BigRand]

Okay so here is the deal, during the course of the MS install my friend found that my EGR tube is cracked at the top.

Now I know many of you have your EGR's blocked off, and I know some people don't and some of those people that don't have it blocked off for a reason.

I would now like to open this up to everyone for pro's and con's of blocking off the EGR, in order to help me and future others figure out if its something we should do based on our individual situations.

I don't want repeat posts, so if it gets said come up with something new or don't post please, I would like this thread to be really comprehensive.

I'll start off

Pro: no EGR = no recycled exhuast = more power

Con: no EGR = no passing emmissions without some sort of ecu trick correct?

 

[VelocitàPaola]

Um... here's why I removed mine:

I don't like engine bay clutter,
I'm pretty sure it wasn't working anyway,
It just gave me another place to look for boost leaks,
I'll polish my intake manifold at some point -- and I'd like to keep it polished,
Screw the environment.

 

[totaleclipse_05]

I had mine blocked in the Talon, but it threw the code (obviously). I threw just the 1 plate sandwiched between the head and the ER valve on the eclipse, so I am going to see if that throws a code still. If it doesn't, it should give you the benefit of blocking it off without completely blocking it off. The pipe will probably still get fairly warm though so it won't be as good as completely taking it out.

 

[dr1665]

Block it off. If you want to avoid a CEL for it, take a close look at the thing and see if you couldn't just drill a small diameter hole into it from the bottom edge of the flange that would go into that chamber where the exhaust goes when it functions. If you could do that, blocking off the port on the head wouldn't prevent the EGR from flow or function and you would avoid the CEL.

Emissions compatability is the only reason to keep it on. I even threw mine away after blocking it off with a plate. The plate looks nice, but now I have a CEL and would fail a visual. Just another reason why Daisy is collecting dust in the garage.

 

[VelocitàPaola]

Just another reason why Daisy is collecting dust in the garage.

And another reason why you need to move to a state that doesn't have emissions testing... like Florida.

 

[BigRand]

Okay now where, is a good place to get the block off kit.....(CI is out for me)

 

[VelocitàPaola]

I'unno... make your own?

I used the soda can trick for the main valve. For the intake manifold part, I cut off the flange from the dump tube and filled the hole with JB Weld.

 

[bullettdsm]

I make my own out of flat stock sheet metal. Used red goobers to seal it up. Pretty simple.

MB

 

[FasterImage]

Cut it out of 16g steel it will be fine! good luck

 

[totaleclipse_05]

I remember seeing a few guys selling their block-off kits on 2gnt for decent prices. Maybe check out there?

 

[link16]

I thought I saw one on Modernperformance.com.

With the portfueler setup you cannot economically use the egr, they say to leave the selenoid attached to the block and hooked up, just block off the two .5" holes, I cut the tube in half and used the two brackets and you can take a "paper" gasket and break off a solid portion and wedge it in there, not pretty but works for cheap.

 

[Ajax]

You can buy the 2 plates of Ebay for $15 or so, or make your own I just recycled my old gaskets that was in place and made my own plates. Again we dont have emisions in Iowa!

 

[Shadow98]

I removed mine because I didn't like the idea of it going back into my IM. Besides, it makes a cleaner engine bay, like Paul said.

 

[BigRand]

so leave the sensor attached to avoid the CEL, but block it off by any means...correct?

 

[dr1665]

so leave the sensor attached to avoid the CEL, but block it off by any means...correct?

Close. Why do you want to block the EGR system? You want to prevent nasty exhaust diluting the intake charge and fouling your intake manifold, right? Right. So it's not that you want to block the EGR system off as much as you want to keep it from sucking in the exhaust. Blocking the outlet on the head (typical block off kit) keeps the exhaust out of the intake, but at what cost?

It helps to know how the system is tested before you can design a way around it. When the ECU closes the IAC and opens the EGR, it's looking for engine vacuum to draw in enough air to maintain idle through the exhaust post on the EGR. You get the CEL when you block this, as you seal the system off. When the ECU opens the EGR, the ECU sees the RPMs drop due to a blocked intake source.

In order to avoid the CELs, you need to make sure the EGR system is in place and everything is connected. All you really want to do is keep the engine from sucking skunk from the exhaust back up. So the trick is to devise a way to block off that exhaust outlet on the head (typical block off kit) while allowing the EGR system to still draw in air. Nothing wrong with fresh air, after all.

Here's the best example of the theory behind my previous suggestion. Poke a hole in the bottom of an empty can. This is where the hot shit gets into the system. You want to seal this off, but still let the system draw in the air it needs to fool the ECU into thinking the system works. Thus, you punch a hole in the side of the can so that, when the ECU trips the system, the engine pulls fresh air through the system instead of sucking foul unpleasantness.

Make sense?

 

[Focker420]

I like the idea your going with dr1665. but we still haven't exposed a main reason to have the egr.
It lowers combustion temps by routing exhaust back into the intake to vary the a/f. which then in turn lowers emissions. Don't know if their is any real hp loss. mabey slight.

If we could use your idea for the FRESH AIR CAN and still be able to control combustion temps, we would be some sweet engineers. just keeping the ball rollin

 

[BigRand]

yeah, reading your two posts in successoin makes sense....but what do you do with the exhaust air coming off the head..I know its not much, but isn't it still an exhaust leak? Or am I missing something still?

 

[Defiant]

I'll start off

Pro: no EGR = no recycled exhuast = more power

Before doing so, you should get a grasp of what the EGR does. Its main purpose is to cool the combustion chamber while not under load. It doesn't function when you're producing power, and so you will gain none by disabling it.

He kept repeating, over and over and over.

 

[Locke]

Randy: Block off the head, so there is no exhaust leak. Leave the valve and the EGR tube in tact. Notch the surface of the EGR valve where it would mate with the head, OR drill holes into that chamber, or whatever. When the EGR opens, exhaust gas cannot enter the IM, because that side is blocked, but since we introduced a "leak" on the hot side of the valve, fresh air is drawn in instead. We need the fresh air coming in to prevent the idle from dropping when the ECU tests the EGR's flow.

I could bust out some mean MS Paint sketches to illustrate, but I don't believe they will make it any more clear, as I am horrible in MS Paint.

Focker420: The EGR lowers combustion temperatures in an effort to lower the emission of NOx, which we don't care about from a performance stand-point. Any HP loss (if any) caused by the EGR is irrelevant, as it only functions at partial throttle.

 

[TSG59_Steve]

Defiant, what do you think of the drill a hole in it version? The main reason I would like to get rid of my EGR and vacuum lines is because of boost/vacuum leaks, but after reading the countless posts you've had on it you seemed to be the most... defiant

 

[totaleclipse_05]

Does anybody have an actual picture where you drill a hole into it? I don't have the EGR valve in front of me, so it's hard to picture where to actually drill.

 

[BigRand]

Before doing so, you should get a grasp of what the EGR does. Its main purpose is to cool the combustion chamber while not under load. It doesn't function when you're producing power, and so you will gain none by disabling it.

He kept repeating, over and over and over.

Been waiting for you to jump in.

Even if my stock one is cracked, would your advice be to replace rather than block it?

 

[Defiant]

Yes.

 

[TSG59_Steve]

Well I guess that answers my question too.

 

[VelocitàPaola]

Yes.

Sorry, I have to disagree. If your EGR system is working fine, then don't touch it. But if the valve is shot, the benefits of an EGR system don't justify the cost of a new valve or the effort to find a used one.