Bulldozer
free ice cream sandwiches
that's the first thing I **** can
All well said Dave,Ditto.
Reason 1-
Carbon. I'm sort of surprised that nobody has mentioned this. Used exhaust gasses are chocked full of carbon, even with good AFR, because of the low percentage of efficiency that an internal combustion engine has. Don't think so? Take the catalytic converter off of your new car and see if it pulls the same numbers at the clinic.
Using Seafoam or some other additive to help remove carbon buildup should be done now and then. Adding unusable carbon to foul things up... Why?
Reason 2-
Inert gas, compressed or ambient is still inert. It does nothing, except work against flame. Throwing intentionally unusable gas and carbon into a machine that needs exactly the opposite to run is counter intuitive.
If you want to help lower combustion temp, do it with colder air charge and ditch stupid ideas, like exhaust crossover.
Using exhaust to power anything, other than a turbocharger or scavenging unburnt fuel (by way of harmonics) is useless.
It looks like a fantastic idea when everything is nice and new, and free of carbon, then it stops working, because exhaust is full of garbage. This is the reason why you LOSE fuel economy and LOSE performance with it!
Quench? ANY of these is a better plan;
- Colder air charge
- Colder fuel charge
- Water injection
- Colder ambient engine bay temp
- Colder oil temp
- Colder water temp
- Checking/ correcting ignition advance
- Better fuel
- Higher flowing exhaust
- Better cylinder heads
- Better pistons
- Better head gaskets
...
These can all be done by doing things like losing E.G.R., losing exhaust crossover, using a better intake manifold, using a better carburetor or even just changing driving habits.
There are so many ways to accomplish the goal of the E.G.R. that don't involve the trash it comes with. E.G.R. falls into the same boat to me as air injection on exhaust or exhaust crossover. I know what it's supposed to do in theory, but what it ends up actually doing on a majority factor, over most of it's life cycle is nonsense.
You'd be way better off adjusting your ignition timing or running higher octane fuel to cure detonation than adding EGR. Assuming of course the air fuel ratio is correct & your not detonating because you're too lean or running too hot. Obviously you'd need to correct that 1st. You have to understand this 1st: From a performance standpoint, you want to maximize the efficiency of the combustion & get the most energy released from it. If it were solely about cranking pressure then it would make sense if you added EGR to the engine at idle the speed & power would increase or for that matter throught the whole RPM range. The fact is that is doesn't. It impedes it. Try this on an EGR equipped car. get it warmed up & at idle & then open the EGR valve & see what happens. Even slightly. EGR was at the time the most cost efficient way to reduce NOx emissions.With caution towards seeming as though I am arguing (Im not, I just though about this and decided to throw it into the discussion),
Lets take the fuel and spark out of the situtation for a second.
So we do a compression check, EXCEPT, with the engines throttle closed to the same point they would be at cruising speed. Should have a lower cranking pressure due to the throttle being closed, right?
Now introduce the air (for simplicitys sake, but it would be exhaust gas when running) through the EGR, downstream of that closed, restricting throttle. Why wouldnt the cranking pressure come up?
EDIT: I agree that the EGR is old technology and is more trouble than its worth after reading this thread. But its still an option to try for reducing detonation at cruise on a car that is at the limit on the compression ratio. With the proper tuning, such as changing orifice sizes in the valve, it could be made to work correctly. And I am sure that the factory setups are not the best way to use EGR, theres alot better parts out there to do it with.
Just to shed a little light on the exhaust crossover just for clarity's sake. It isn't the same as EGR. That's used primarily for heating the intake up for quicker warm ups during cold starts. But no exhaust is reintroduced into the engine.
Air injection is fresh air pumped into the exhaust side of the engine, sometimes directly into the exhaust ports & sometimes downstream but always before the catalytic converters. It's used to improve catalyst efficeincy by increasing the catalyst's temperature. Running air injection without a catalytic converter can lead to burnt valves. So remove it if you're not running a cat.
As for the filling of the volume of the combustion chamber(back to the OP here), the engine is going to draw a given volume into the cylinders regardless, the only way to improve efficiency is to actually introduce something into the cylinder that is going to burn.
so on a well tuned HEAVY TRUCK engine they are beneficial??? or in my case a DIRECT DRIVE airboat??? I mea'n I'm gonna have to give it a whirl to see for sure...on an airboat with DIRECT DRIVE the gains are seen easily so I guess its time to find out...?????
so on a well tuned HEAVY TRUCK engine they are beneficial??? or in my case a DIRECT DRIVE airboat??? I mea'n I'm gonna have to give it a whirl to see for sure...on an airboat with DIRECT DRIVE the gains are seen easily so I guess its time to find out...?????
You keep bringin up tha air boat.....so I gotta ask. Is the prop really that much of a load? School me. I don't know anything about um.
yepp it's a constant load and the load increases with rpm's...I run 87 octane with ethanol so looking for anything that makes more low end torque so I can add pitch to the variable pitch carbon fiber prop...I'll just have to try it and see what it does at the tachometer
You ran 20* hotter because w/o the EGR it runs leaner. As for the "EGR cold air induction" it won't offer any value for performance. You're just cooling down non-combustables.Run your egr through a Small intercooler In front of the radiator. Egr cold air induction! I will continue to run one if i can once its working properly. Really does no harm other than cluttering the engine compartment with 2 more hoses...high lift cams need not apply as their low vacuum may fool egr activation. I noticed my little truck ran about 20 degrees hotter without egr hooked up or plugged. I always thought pcv introduced under the carb was ludicrous too. I think some modern cars dont have egr as they use MAF meterz that cant read egrdilution as it doesnt pass through the meter? I know thats an issue on turbo cars when the blow off valve opens, the motor controller is like " what happened to all that metered air i let in and accountwd for?"