EGR System 85 C4 ?????

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EGR System 85 C4 ?????

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EGR System 85 C4 ????? - 4/6/2006 12:00:09 AM

mjames

Posts: 10
Joined: 1/17/2006
Status: offline

I took my intake runners off to polish them and found the runners very clogged with exhaust soot. It was also very evident in the plenum and throttle body. I want to eliminate the entire EGR system and keep the brand new high flow cat I just bought. I'm presently porting the headers and now would be the time to weld the EGR ports shut. What are the potential computer problems versus the performance benefit? I don't have any emissions problems or checks where I reside. I'm woried this move will foulup the ECM and I'll have problems. Has any one done this? HELP! The SPECS: I run stock cam, high flow cold air box, stock throttle body with coolant line eliminated, throttle body air foil, Hypertech stage 2 chip, Hypertech 55,000 volt coil, port matched everything including ported headers, high flow cat, balance tube, 4 glass pack for final exhaust.

Post #: 1

RE: EGR System 85 C4 ????? - 4/6/2006 2:29:27 PM

Clayton

Posts: 115
Joined: 10/13/2005
From: Athens Georgia
Status: offline

Hi. This is an educated guess. I would not do this for two reasons. One is that your service engine soon light might come on because of a code 32 which is EGR valve malfunction. The reason I say this is because my car flashed a code 32 and it was the egr valve that had to be replaced. The other reason is that many states are introducing emmisions testing. What if your state decides to do this and you have welded up the egr ports? I wouldn't do it myself but this is just my opinion. I don't know much about the egr system and that is why I call the first reason a guess. Hope this helps a little.

_____________________________

Clayton Morang

85 Corvette
03 Harley Electraglide Standard

(in reply to mjames)

Post #: 2

RE: EGR System 85 C4 ????? - 4/6/2006 6:48:21 PM

mech259

Posts: 1760
Joined: 1/22/2006
From: Lumberton, Texas
Status: offline

Most Chevy's around that year uses vacuum and exhaust pressure to open egr valve. It has a vacuum solenoid that is commanded open or shut by the ECM. The way your ECM determines if the valve opens or not is by watching the O2 sensor. When valve is commanded open, it's looking for the O2 to rich within so many milliseconds. If you weld your ports up, not only will the light come on, but you could cause engine detonation (pinging), because the EGR gases help to cool combustion temperature, and if the temperature gets to hot, you get detonation, sometimes more than the Electronic Spark control system can overcome by retarding your timing to help with detonation. WHEW! Sorry, I sometimes tend to ramble on, kinda sound like a school teacher.