K20A3 - Tuning for Economy

[whatthe]

Leaning it out would be mpg friendly, but not necessarily 'eco' friendly. NOx emissions sky-rocket until you start getting into ultra-lean burn capabilities.

I can idle my 17 year old Swift under 21:1 a/f and lean it out fairly far while cruising, but it will never approach the ultra-lean burn zone

[Vince-HX]

I'm thinking you could adapt a Insight Cat and program Hondata to richen up after a certain amount of time spent in lean burn to do a NoX burn.

So there you go


And speaking of ultra lean burn, direct injection is the way to go. I remember reading something about mixtures of 40:1 and higher are possible.

[c0da]

What you need is that magical 200mpg carburetor!

[Red]

Originally Posted by Vince-HX

I'm thinking you could adapt a Insight Cat and program Hondata to richen up after a certain amount of time spent in lean burn to do a NoX burn.

So there you go

Do able but you'd have to fork for a new one. I pretty sure junk yards aren't allowed to sell cats.....

[SVOboy]

Originally Posted by Red

Do able but you'd have to fork for a new one. I pretty sure junk yards aren't allowed to sell cats.....

This is true. Alternatively, you could get buddy buddy with someone who works at honda and wait to see if something passes through.

[greenwar]

Raising the Vtec engagement to 2700 will be nice. I try shifing my civic at 2200-2500 but the lack of torque is just painful. I feel that an accord 5spd is more suited for hypermiling due to its higher low end torque. A 94 accord auto can do 50-55mph staying at 2k rpm. I am getting better mpg out of a 94 accord than my ep3.

[dann_04]

I have though about getting kpro and tuning for mpgs, but it is fairly expensive. you would bebetter off first dropping your tranny and adding a 6th gear from the acura tsx. It takes your rpms from 3500 at 65mph to 3000.
search on ephatch.com and you should find the howto. If not, pm me i have the url on my work computer.

Also for those of you questioning the k20a3 as an i-vtec engine, it is. Vtec is simply valve timeing(and lash) electronically controlled. The intake side has a high and low cam profile. The exhaust does not. Honda did this to tune it for economy and emissions. At 2200 rpms the vtec solenoid locks and both valves operate on the higher cam lobe. as for the i it simply stands for with inteligence which is what honda calls it when they ad the variable camshaft angle. So a k20a3 is an i-vtec engine. It is designed for economy and lower smog emissions. Plus it says ivtec right on the side of the ep3 in vinyl decals lol.

[reformed]

Originally Posted by Vince-HX

I'm thinking you could adapt a Insight Cat and program Hondata to richen up after a certain amount of time spent in lean burn to do a NoX burn.

So there you go


And speaking of ultra lean burn, direct injection is the way to go. I remember reading something about mixtures of 40:1 and higher are possible.

I agree that direct injection is great and much more efficient, but you run into the problem of cylinder wash which causes a decent amount of wear and tear over the traditional style injection. I'm just waiting to see how long these new cars are going to last with direct injection from the factory.

[jonr]

IMO, HCCI plus direct injection plus variable compression (using delayed intake valve closing) is the way to go.

[EP3]

Originally Posted by greenwar

Raising the Vtec engagement to 2700 will be nice. I try shifing my civic at 2200-2500 but the lack of torque is just painful. I feel that an accord 5spd is more suited for hypermiling due to its higher low end torque. A 94 accord auto can do 50-55mph staying at 2k rpm. I am getting better mpg out of a 94 accord than my ep3.

Yeah I hear ya. I hit 29mpg mark. I was going for 30mpg, but I am pretty impressed for my first time. I know I can get better though. This is mostly city driving. When I move I will be mostly on highways. So we will see. My wifes 05 Honda civic 4-door lx auto gets sometimes in the 40s without really going crazy. But at highway speeds it is around 2k ish.