To EGR or Not to EGR that is the question!

[eastendmedic]

So as this process of getting my 60 to run better system by system I have a question for you all. I had originally disabled my EGR by clamping the top hose and it ran great...no Ping..

I recently replaced the thermostat as mine was stuck open and never getting to operating temp. Now that I have gotten the 60 up to temp....damn thing pings in 3rd and 4th gear on long hills and some flat runs when I am up to 60-65mph. I adjusted the mixture and set the timing....the BB is just below the line in the window.

I unclampped the EGR hose and now it is chuggy/sputtery as hell (like it was before)....and upon accleration the vac gauge needle sputters like hell and is reading like 5" but no ping at all. The EGR tests out fine...the modulator is probably toast...I am not sure...

This 60 is smogged and will have to pass emmisions soon.

Should I Disable the EGR and just retard the timing till no ping....is that a good idea? Anyone have an idea how far to retard..is it below 7*btdc?

Or.

Just deal with the chuggy EGR....I hate it btw... which is worse for the motor...a vac leak created by a crappy modulator/EGR system

or a disable EGR...

Gurus' rule in please.

thanks

Matt

 

[ellington12]

what kind of emmisions testing do you have out there? do they run cars on dynos?

if they test for oxides of nitrogen, you'll need a fully functioning EGR system for sure. your air injection system is very crucial as well as far as your CO and HC levels.

out here in CA, they are very anal about not only what comes out the tailpipe, but whether all of your smog equipment is present and hooked up. they can fail you for a disconnected vacuum line if they're really anal and going completely "by the book."

 

[eastendmedic]

Yeah...NY is anal too.....especially in the Long Island NYC area...however they aren't too critical about hoses....I know they won't really look to hard....they dyno everything unless it is full time 4wd....BTW last time I smogged this 60 it had a Webber on it and the EGR was disabled...the NOX was the lowest reading..weird huh.


I know the Air pump tricks to get more air for the test to dilute the readings.

But I want to know if the EGR is better disabled or enabled for every day operations.

 

[Dave-T]

A seasoned engine builder I was talking to the other day about milling my head to increase compression said that because I have an EGR system it will keep the chamber cooler and reduce pinging. Maybe someone else could confirm this.

 

[ellington12]

true...the EGR system is meant to control NOX but it does so by basically recycling some of the exhaust gases and routing it to the intake; this effectively cools down the combustion chamber temperature which in turn inhibits pinging. pinging occurs when the air/fuel mixture self ignites instead of igniting when the spark plugs fires. if you mill your head, you increase the compression in the cylinders which can make your engine more prone to pinging. a way around this is to use high octane gas. i've heard of people using aviation fuel if they have really high compression engines.

i believe you can do a search for EGR and there are people on this board running without EGR and champion the increase in performance. my rig is still bone stock with all of the emissions plumbing still intact so i personally can't really say.

eastendmedic,

CA is so stringent that just about every performance mod for the 60 is illegal...a real bummer.