RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   Is EGR mod worth it? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/egr-mod-worth-27209/)

ROSHX7 10-22-01 05:18 AM

Is EGR mod worth it?
 
I was thinking of getting rid of my EGR Valve and was wondering if its worth the trouble? What benefits is there to REMOVING the thing?

RX-7 GT 10-22-01 05:41 AM

:rolleyes: ....(counting in head 1,2,3) um no. no gains. just easy access to whatver is back there:D i have an egr plate from k2rd if you want to buy it:D

copandengr 10-22-01 10:59 AM

EGR Valve 101
 
The purpose of the Exhaust Gas Recirculation valve is to stop the "pinging" or detonation sometimes experienced at lower engine speeds and higher engine loads. I have never heard this in my '86NA, but in a piston engine it sounds like you are crunching rocks.

It does this by introducing exhaust gasses into the intake system and thereby reducing the combustion chamber temperatures. The idea is to eliminate the conditions under which detonation happens. It is supposed to be taken out of of the loop under wide open throttle use.

The problem with the EGR valve is that it is prone to loading up with carbon and sticking in the open or partially open position. This will make the engine run badly and seriously affect the fuel economy. The diaphragm is also prone to rotting and then leaking vacuum when it is told to open up by the ECU.

Removing it is simply a matter of blocking off the mounting area after the EGR is taken off. You also need to cap off the vacuum line fitting on the solenoid that controls the valve. If you have a jig saw, a blocking plate is easily made out of thick (1/4 to 3/8 inch or so) aluminum by using the gasket as a template.

Have at it. The removal is certainly less expensive that replacing it, but do not expect any benefits from taking it off if it is functioning normally. The operation of the EGR valve when it is working properly is transparent (meaning you do not know it is there) and does not adversly affect your engine in any way. It does have the benefit of reducing or eliminating detonation, so you will need to be aware of this possibility and drive accordingly.

usmcjsy 08-10-03 09:59 AM

I could be wrong but I do not believe the EGR is for the engine pinging. I belive it is to burn exhuast gasses that are not completly burnt. If it was for any mechanical benifit to the engine and not emisions why do Jspec engines not have a EGR? I am not positive on this but I have a Jspec motor and there is no EGR.

NZConvertible 08-11-03 06:07 AM


Originally posted by copandengr
The purpose of the Exhaust Gas Recirculation valve is to stop the "pinging" or detonation sometimes experienced at lower engine speeds and higher engine loads.
That's completely wrong. The EGR is for reducing emissions, that's all. I found this with a Google search:

The exhaust gas recirculation (EGR) system is used to reduce the amount of NOx created by the engine. It does this by diluting the air/fuel mixture with a small amount of inert gas (usually less than 10% of the total mixture); exhaust gas is used since it contains only a small amount of oxygen (and is readily available). Adding it has the effect of lowering the combustion temperature below the point at which nitrogen combines with oxygen to form NOx. When working properly, the EGR does not open when the engine is cold, at idle or WOT. A defective EGR can have a severe impact on the quality of idle.

As mentioned, the EGR valve only operates at low load, so you won't notice any change in performance from removing it. It's only worth doing if it's broken or you're removing the vacuum rack and solenoids.

Scott 89t2 08-11-03 07:37 AM


it has the effect of lowering the combustion temperature
sounds like it helps prevent pinging to me :D

Fitness Stain 08-11-03 10:26 AM

the j-spec flows better :D
due to it not being there at all

NZConvertible 08-12-03 01:24 AM


Originally posted by Scott 89t2 sounds like it helps prevent pinging to me
The EGR valve is not used at high load where pinging occurs, so it won't help at all.

bottlejockey 09-08-03 02:17 PM

i agree with convetrible.


All times are GMT -5. The time now is 12:32 AM.


© 2024 MH Sub I, LLC dba Internet Brands