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73-87 Chevy _ GMC Trucks => 73-87 Chevy & GMC Trucks => Topic started by: 81Cheyenne on November 21, 2007, 03:51:30 pm

Title: EGR?
Post by: 81Cheyenne on November 21, 2007, 03:51:30 pm: I recently bought a used Edelbrock Performer intake to put on my 305. It's the spread-bore version with EGR. Most of the emissions related connections have already been eliminated and at some point in the future I'll be changing over to headers as well. Is s there any advantage (or disadvantage) to blocking off the EGR on the intake? There is no emissions testing in this state so that's not a problem. I also noticed that there are 2 holes cast in the floor of the plenum chamber, would I need to plug these as well? Oh, sorry, It's on an 81 C10 LWB 2WD.
thanks.
Title: Re: EGR?
Post by: werewolfx13 on November 21, 2007, 05:34:20 pm: Having the EGR valve there and functioning keeps cylinder temps down a bit i think, but I've never had a problem with em blocked off..one of the POs of my truck blocked mine off, and I blocked off the one on the '84 I used to have because it was in the way where I wanted my hand choke brackets when I put a Holley on it.
Title: Re: EGR?
Post by: VileZambonie on November 21, 2007, 07:11:43 pm: No problems blocking it off...Go for it.
Title: Re: EGR?
Post by: KojaK 79k10 on November 23, 2007, 03:48:09 pm: if pieces of the system are missing then go ahead and block it off but what wearwolf said is correct. the cylinder temperatures are supposed to be lower. the purpose of the EGR is to re burn unburned hydrocarbons to reduce emissions. In these older systems it neither helps nor hurts to have it there.
Title: Re: EGR?
Post by: cline100 on November 23, 2007, 06:48:06 pm: You can't reburn what's allready been burned. The purpose of the Exhaust Gas Recerculation system is to reduce Nitrogen Oxide, or NOx Emissions. It does this by reducing the amount of oxegyn in the cylinder by sending in exhaust gasses, thus reducing NOx, which form when fuel is burned at high temperature. Removing the system won't nescessarily cause problems, but in order to compensate, you'll want to run just a little bit rich, and use fuel to keep your cumbustion temperatures down. Of course, this won't help emissions at all, but it will keep your engine running longer.
Title: Re: EGR?
Post by: VileZambonie on November 23, 2007, 07:02:00 pm: Yes EGR is an inert gas. It will not reduce HC emissions only Oxides of Nitrogen. NOx gasses are produced when combustion temps exceed 2500°F but if your engine is producing high levels of NOx I would suggest a good decarbonizing and check of the ignition timing and a/f ratio. EGR will drastically reduce engine power so if you're hot rodding it up just unplug it and you'll see a huge difference without it.
Title: Re: EGR?
Post by: 81Cheyenne on November 27, 2007, 12:31:53 pm: Cool. What about the holes inside the plenum? Do I need to plug those somehow or are they ok just left alone if I take off the EGR?
Title: Re: EGR?
Post by: VileZambonie on November 27, 2007, 03:31:35 pm: You can actually just leave the valve on and remove and plug the vacuum hose. I have a bunch of EGR block off plates if anyone needs one.
Title: Re: EGR?
Post by: 81Cheyenne on November 28, 2007, 07:57:23 am: Quote from: VileZambonie on November 27, 2007, 03:31:35 pm
I have a bunch of EGR block off plates if anyone needs one.

I'm interested in one of those plates.
Title: Re: EGR?
Post by: VileZambonie on November 28, 2007, 07:00:29 pm: OK I have 6 of them left
Title: Re: EGR?
Post by: Captkaos on November 29, 2007, 09:53:57 am: You don't have one for a TPI do you?
Title: Re: EGR?
Post by: VileZambonie on November 29, 2007, 06:00:51 pm: If it'll fit your manifold you're more than welcome to one. I've had these for years. I had the machine shop make me a bunch of em...

(http://i6.photobucket.com/albums/y228/Sabaka454/egr001.jpg)

(http://i6.photobucket.com/albums/y228/Sabaka454/egr002.jpg)

(http://i6.photobucket.com/albums/y228/Sabaka454/egr003.jpg)

(http://i6.photobucket.com/albums/y228/Sabaka454/egr004.jpg)
Title: Re: EGR?
Post by: DnStClr on November 29, 2007, 08:53:35 pm: If you get Pugsy to make em they'll be stainless and probably coated with polished copper. Ha!
Title: Re: EGR?
Post by: JJSZABO on November 30, 2007, 11:20:02 am: Quote from: DnStClr on November 29, 2007, 08:53:35 pm
If you get Pugsy to make em they'll be stainless and probably coated with polished copper. Ha!

LOL :D
Title: Re: EGR?
Post by: VileZambonie on December 07, 2007, 07:05:23 am: I dropped it in the mail 4 u yesterday so be on the look out for it.
Title: Re: EGR?
Post by: Captkaos on December 07, 2007, 12:44:39 pm: I haven't had time to measure it yet, but it might work, I would just have to trim one edge off...
Title: Re: EGR?
Post by: VileZambonie on December 23, 2007, 11:45:55 am: 81 Cheyenne, did the plate ever arrive?
Title: Re: EGR?
Post by: 81Cheyenne on December 23, 2007, 12:50:36 pm: Quote from: VileZambonie on December 23, 2007, 11:45:55 am
81 Cheyenne, did the plate ever arrive?
Nope. Not yet.
Title: Re: EGR?
Post by: VileZambonie on December 23, 2007, 03:35:36 pm: I will send you another one. Gotta love the US post office....
Title: Re: EGR?
Post by: VileZambonie on December 30, 2007, 09:33:18 am: Please tell me you got the second one!
Title: Re: EGR?
Post by: 81Cheyenne on December 30, 2007, 12:06:17 pm: Quote from: VileZambonie on December 30, 2007, 09:33:18 am
Please tell me you got the second one!
Haven't seen it yet.
Title: Re: EGR?
Post by: 123 pugsy on December 30, 2007, 05:47:51 pm: Quote from: DnStClr on November 29, 2007, 08:53:35 pm
If you get Pugsy to make em they'll be stainless and probably coated with polished copper. Ha!

Almost Don. :D :D I use aluminum for block off plates.

Hey Chris. I have a TPI one that I made up if you want it. Its 1/4" thick aluminum.
I can mail it to you.
Title: Re: EGR?
Post by: Captkaos on December 31, 2007, 10:09:25 am: Pugsy, thanks for the offer, I broke down made one out of some 1/4" steel I had laying around 2 weeks ago.