I know that egr recirculates a small percentage of the exhaust gases back to the combustion chamber. Which is suppose to reduce cylinder combustion tempertures along with reduced emissions...

Does egr help with fuel economy and HP? I assume since it's adding more combustible fuel to the fire it would increase fuel economy and maybe Horse Power. Unless the exhaust gases are not combustible and it's just the fuel and ignition combustion being able to burn the gases up in the cylinder...

Right now, on my 84' D150 i'm using a intake off a 72' Dart that does not have egr. I have a aluminum welded intake that does have egr i thought maybe later on i might try the aluminum with egr to see what difference it makes...I believe chrysler didn't start using egr until 73'

Right now, my truck isn't doing too bad on gas milage especially since i leaned out the air/fuel screw it was 3 turns out which ended up being too rich i'm at about 1 1/2 turns out right now and that seems to be pretty close...i know that all off the little tuning and setup features can make a difference in the fuel economy game...i assume that water injection will also boost the MPG a little too

Also i assume since egr is putting used exhaust gases into the combustion chamber that it increase carbon build up. So is it better to have egr or not ?

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1984' Dodge D150 Utiline Bed
Slant 6 225, Holley 1920 Carb
A833 4 Speed O/D Transmission

You can carry more timing advance at cruise settings with EGR, so economy can be greater with than without.

EGR is inactive at high throttle settings, so doesn't effect power.

CJ

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Part of Tyrde-Browne Racing

This is correct, but up to a certain point. If the engine is not efficient it will only benefit to a certain point then become ineffective, there also is a pushover point where you can have more economy and lose power, or more power and less economy.

If the engine's potential is not upgraded you will gain a couple of mpg at best by water injection and EGR, then it will top out. You may get more out of it, if the engine had upgraded compression to 9:1.

To put this into juxtaposition, the Feather Duster used more EGR than any other model to knock back the ton of timing it had dialed into it. Got really good mileage, but I would not feel comfortable merging into modern day rush hour on the interstate with one....

-D.Idiot

I'm hoping he isn't going to attempt a Feather Duster Curve in a pickup!

CJ

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Part of Tyrde-Browne Racing

None of the power, none of the mileage, and way too much advance with a carb that isn't calibrated for it. As much as you can take up room in the cylinder with inert gasses and vapor to lower the displacement of the engine during cruise, there is a point there also where too much of both is not a good thing and the engine's temporary smaller displacement and lack of efficiency won't be able to lug that brick around too well. All the components have to be well thought out to make it all work correctly, you don't just dial in 20 extra degrees of advance and bandaid it with spent exhaust gas then drown it with a spritz of water vapor on an engine with a VE less than 80%, and a DCR under 8....



-D.Idiot

I I agree on the water injection and prefer it over using EGR gases to help knock back the timing. I blocked off the EGR port on the intake and went with water injection which kicks in at 2000 rpm. It makes a big difference when running 55 degrees timing or more.....no pinging what so ever.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Are you advancing or retarding the timing when you go toward 0 TDC? In my mind your advancing it but i'm not sure that's correct...

Without EGR or water injection do you think the timing adjustment would be better going closer or further away from 0 TDC?

Later on, whenever i pull the distributor i'm going to replace the vacuum pot with the VC239 that Reed recommended awhile back. He felt like that would be the right one since he said with a truck or van "your trying to move a brick with a small motor"

Right now the truck is running pretty good especially from where it was when i bought it and i'm sure the motor probably has 200,000 miles on it...i'm going to consistently work on doing the right things to have a balanced descently tuned truck and try to avoid putting together a mess that doesn't work out for good fuel economy and reasonable performance

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1984' Dodge D150 Utiline Bed
Slant 6 225, Holley 1920 Carb
A833 4 Speed O/D Transmission

Advance makes things occur more before top dead center...so if you start at 0 and the distributor advances the ignition it will move the timing toward BTDC... if you retard the timing that will move the timing toward ATDC...

-D.Idiot

Closer to 0 TDC, in other words if your at 10 degrees initial now and it pings you want to go back to 5 or 6 degrees initial for less timing.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG