Re: cold start sluggishness
 

"bllsht" <nospam@dot.net> wrote in message
news:bbsmn2hjabesvdtcdh00hvgi3ip3tulc6j@4ax.com...
> On Sat, 09 Dec 2006 11:51:07 -0800, Outatime <user@example.net> wrote:
>
> >bllsht wrote:
> >
> >> Lack of EGR will not cause a rich condition, injected or not.
> >
> >It did on my old 78 Dodge with the 'lean burn' system; it was set up so
> >that the valve was wide open at any throttle setting except idle, and
> >the mains were oversized a bit to compensate. After rejetting, I ended
> >up with better throttle response and another 1.5 mpg, which was a big
> >deal because it only got 10 mpg to begin with.
>
> Since EGR doesn't cause a lean condition, larger jets would do nothing
> to 'compensate' for it. Exhaust gas is inert. It doesn't change the
> mixture, it only takes up space to keep peak combustion temperature
> down.
>
> >
> >Another old '74 wagon I drove ran like a champ with the vacuum tube
> >removed. No one I knew ever left theirs hooked up. I know the vacuum
> >controls on EGRs now are more refined, but the idea of shoving exhaust
> >gasses back into an engine to lower combustinon temps still seems silly
> >to me. Even water injection made more sense to me.
>
> No doubt EGR in the 70s & 80s wasn't good, but today, you probably
> wouldn't notice a difference by disconnecting it. Other than the MIL
> being on, that is.
>
> I always wondered about water injection too. Perhaps it's more costly,
> or has other drawbacks. Maybe the water vapor that gets past the rings
> condensing in the combustion chamber could be a problem.
>
Reliable storage and delivery problems. How are you going to supply water,
when the ambient temperature is -20º and the car is left out all night?

Earle

Re: cold start sluggishness
 

On Sat, 09 Dec 2006 11:55:14 -0800, Outatime <user@example.net> wrote:

>Lon wrote:
>
>> Think most systems do check for the amount of exhaust being
>> recirculated, so would expect a code on most mods. With modern FI it
>> tends not to be as bad as the older stuff when EGR first started.
>
>Figures. I'll probably get a code, but I'd like to see how much better
>it runs just for laughs. There's always a way to get around something
>if you really want to. Truckers figured out a long time ago that
>getting around computer governors was an easy task, IF you didn't mind
>the speedometer being disabled. Nowadays we get a code set on that too
>if we mess with input sensors.

First thing you'll have to overcome is how to block off EGR on a
vehicle that's not equipped with it.

Re: cold start sluggishness
 

On Sat, 09 Dec 2006 11:55:14 -0800, Outatime <user@example.net> wrote:

>Lon wrote:
>
>> Think most systems do check for the amount of exhaust being
>> recirculated, so would expect a code on most mods. With modern FI it
>> tends not to be as bad as the older stuff when EGR first started.
>
>Figures. I'll probably get a code, but I'd like to see how much better
>it runs just for laughs. There's always a way to get around something
>if you really want to. Truckers figured out a long time ago that
>getting around computer governors was an easy task, IF you didn't mind
>the speedometer being disabled. Nowadays we get a code set on that too
>if we mess with input sensors.

First thing you'll have to overcome is how to block off EGR on a
vehicle that's not equipped with it.

Re: cold start sluggishness
 

On Sat, 09 Dec 2006 11:55:14 -0800, Outatime <user@example.net> wrote:

>Lon wrote:
>
>> Think most systems do check for the amount of exhaust being
>> recirculated, so would expect a code on most mods. With modern FI it
>> tends not to be as bad as the older stuff when EGR first started.
>
>Figures. I'll probably get a code, but I'd like to see how much better
>it runs just for laughs. There's always a way to get around something
>if you really want to. Truckers figured out a long time ago that
>getting around computer governors was an easy task, IF you didn't mind
>the speedometer being disabled. Nowadays we get a code set on that too
>if we mess with input sensors.

First thing you'll have to overcome is how to block off EGR on a
vehicle that's not equipped with it.

Re: cold start sluggishness
 

On Sat, 9 Dec 2006 20:01:17 -0700, "Earle Horton"
<el_anglo_burgues@usa.com> wrote:

>"bllsht" <nospam@dot.net> wrote in message
>news:bbsmn2hjabesvdtcdh00hvgi3ip3tulc6j@4ax.com.. .
>> On Sat, 09 Dec 2006 11:51:07 -0800, Outatime <user@example.net> wrote:
>>
>> >bllsht wrote:
>> >
>> >> Lack of EGR will not cause a rich condition, injected or not.
>> >
>> >It did on my old 78 Dodge with the 'lean burn' system; it was set up so
>> >that the valve was wide open at any throttle setting except idle, and
>> >the mains were oversized a bit to compensate. After rejetting, I ended
>> >up with better throttle response and another 1.5 mpg, which was a big
>> >deal because it only got 10 mpg to begin with.
>>
>> Since EGR doesn't cause a lean condition, larger jets would do nothing
>> to 'compensate' for it. Exhaust gas is inert. It doesn't change the
>> mixture, it only takes up space to keep peak combustion temperature
>> down.
>>
>> >
>> >Another old '74 wagon I drove ran like a champ with the vacuum tube
>> >removed. No one I knew ever left theirs hooked up. I know the vacuum
>> >controls on EGRs now are more refined, but the idea of shoving exhaust
>> >gasses back into an engine to lower combustinon temps still seems silly
>> >to me. Even water injection made more sense to me.
>>
>> No doubt EGR in the 70s & 80s wasn't good, but today, you probably
>> wouldn't notice a difference by disconnecting it. Other than the MIL
>> being on, that is.
>>
>> I always wondered about water injection too. Perhaps it's more costly,
>> or has other drawbacks. Maybe the water vapor that gets past the rings
>> condensing in the combustion chamber could be a problem.
>>
>Reliable storage and delivery problems. How are you going to supply water,
>when the ambient temperature is -20º and the car is left out all night?
>
>Earle
>


Good point! :-)

Re: cold start sluggishness
 

On Sat, 9 Dec 2006 20:01:17 -0700, "Earle Horton"
<el_anglo_burgues@usa.com> wrote:

>"bllsht" <nospam@dot.net> wrote in message
>news:bbsmn2hjabesvdtcdh00hvgi3ip3tulc6j@4ax.com.. .
>> On Sat, 09 Dec 2006 11:51:07 -0800, Outatime <user@example.net> wrote:
>>
>> >bllsht wrote:
>> >
>> >> Lack of EGR will not cause a rich condition, injected or not.
>> >
>> >It did on my old 78 Dodge with the 'lean burn' system; it was set up so
>> >that the valve was wide open at any throttle setting except idle, and
>> >the mains were oversized a bit to compensate. After rejetting, I ended
>> >up with better throttle response and another 1.5 mpg, which was a big
>> >deal because it only got 10 mpg to begin with.
>>
>> Since EGR doesn't cause a lean condition, larger jets would do nothing
>> to 'compensate' for it. Exhaust gas is inert. It doesn't change the
>> mixture, it only takes up space to keep peak combustion temperature
>> down.
>>
>> >
>> >Another old '74 wagon I drove ran like a champ with the vacuum tube
>> >removed. No one I knew ever left theirs hooked up. I know the vacuum
>> >controls on EGRs now are more refined, but the idea of shoving exhaust
>> >gasses back into an engine to lower combustinon temps still seems silly
>> >to me. Even water injection made more sense to me.
>>
>> No doubt EGR in the 70s & 80s wasn't good, but today, you probably
>> wouldn't notice a difference by disconnecting it. Other than the MIL
>> being on, that is.
>>
>> I always wondered about water injection too. Perhaps it's more costly,
>> or has other drawbacks. Maybe the water vapor that gets past the rings
>> condensing in the combustion chamber could be a problem.
>>
>Reliable storage and delivery problems. How are you going to supply water,
>when the ambient temperature is -20º and the car is left out all night?
>
>Earle
>


Good point! :-)

Re: cold start sluggishness
 

On Sat, 9 Dec 2006 20:01:17 -0700, "Earle Horton"
<el_anglo_burgues@usa.com> wrote:

>"bllsht" <nospam@dot.net> wrote in message
>news:bbsmn2hjabesvdtcdh00hvgi3ip3tulc6j@4ax.com.. .
>> On Sat, 09 Dec 2006 11:51:07 -0800, Outatime <user@example.net> wrote:
>>
>> >bllsht wrote:
>> >
>> >> Lack of EGR will not cause a rich condition, injected or not.
>> >
>> >It did on my old 78 Dodge with the 'lean burn' system; it was set up so
>> >that the valve was wide open at any throttle setting except idle, and
>> >the mains were oversized a bit to compensate. After rejetting, I ended
>> >up with better throttle response and another 1.5 mpg, which was a big
>> >deal because it only got 10 mpg to begin with.
>>
>> Since EGR doesn't cause a lean condition, larger jets would do nothing
>> to 'compensate' for it. Exhaust gas is inert. It doesn't change the
>> mixture, it only takes up space to keep peak combustion temperature
>> down.
>>
>> >
>> >Another old '74 wagon I drove ran like a champ with the vacuum tube
>> >removed. No one I knew ever left theirs hooked up. I know the vacuum
>> >controls on EGRs now are more refined, but the idea of shoving exhaust
>> >gasses back into an engine to lower combustinon temps still seems silly
>> >to me. Even water injection made more sense to me.
>>
>> No doubt EGR in the 70s & 80s wasn't good, but today, you probably
>> wouldn't notice a difference by disconnecting it. Other than the MIL
>> being on, that is.
>>
>> I always wondered about water injection too. Perhaps it's more costly,
>> or has other drawbacks. Maybe the water vapor that gets past the rings
>> condensing in the combustion chamber could be a problem.
>>
>Reliable storage and delivery problems. How are you going to supply water,
>when the ambient temperature is -20º and the car is left out all night?
>
>Earle
>


Good point! :-)

Re: cold start sluggishness
 

bllsht wrote:

> Since EGR doesn't cause a lean condition, larger jets would do nothing
> to 'compensate' for it. Exhaust gas is inert. It doesn't change the
> mixture, it only takes up space to keep peak combustion temperature
> down.

We will have to agree to disagree on this one. IMO, EGR porting is
nothing more than a poorly-controlled vacuum leak; increase or decrease
the flow into the intake manifold below the carburetor venturi and the
fuel mixture changes. This can be easily demonstrated by disconnecting
the diaphram vacuum tube, apply enough suction to open the pintle valve
to introduce lots of inert exhaust gas, and observe the engine die
immediately from an excessively lean mixture. Smog techs often used
this method to verify proper EGR valve operation.

Re: cold start sluggishness
 

bllsht wrote:

> Since EGR doesn't cause a lean condition, larger jets would do nothing
> to 'compensate' for it. Exhaust gas is inert. It doesn't change the
> mixture, it only takes up space to keep peak combustion temperature
> down.

We will have to agree to disagree on this one. IMO, EGR porting is
nothing more than a poorly-controlled vacuum leak; increase or decrease
the flow into the intake manifold below the carburetor venturi and the
fuel mixture changes. This can be easily demonstrated by disconnecting
the diaphram vacuum tube, apply enough suction to open the pintle valve
to introduce lots of inert exhaust gas, and observe the engine die
immediately from an excessively lean mixture. Smog techs often used
this method to verify proper EGR valve operation.

Re: cold start sluggishness
 

bllsht wrote:

> Since EGR doesn't cause a lean condition, larger jets would do nothing
> to 'compensate' for it. Exhaust gas is inert. It doesn't change the
> mixture, it only takes up space to keep peak combustion temperature
> down.

We will have to agree to disagree on this one. IMO, EGR porting is
nothing more than a poorly-controlled vacuum leak; increase or decrease
the flow into the intake manifold below the carburetor venturi and the
fuel mixture changes. This can be easily demonstrated by disconnecting
the diaphram vacuum tube, apply enough suction to open the pintle valve
to introduce lots of inert exhaust gas, and observe the engine die
immediately from an excessively lean mixture. Smog techs often used
this method to verify proper EGR valve operation.