K20A3 - Tuning for Economy

[I-S]

So, I thought I'd begin posting here with an old thread revival.

I have a UK honda accord wagon:



As you can see, what we are sold as the Accord is the Acura TSX in the USA (what you are sold as Accord is the Honda Inspire in Japan, not sold in europe). This has a K20A6, which is basically the same as the A3, but with the aluminium rather than plastic inlet manifold. 5-speed manual.

So, this thread concerning the A3 is of great interest as I think it likely any improvements made to the A3 should be directly portable to the A6.

So far, my fuel economy is as follows:



Note that the mpg numbers are in miles per imperial gallon. The 33.2mpg(imp) average = 27.7mpg(US).

Is there anything further to report on the tuning of the A3?

Also interesting discussion here on direct injection. Since there is no legislation in europe regarding NOX (or at least nothing like as stringent as the USA) such engines are fairly commonplace here. VAG have their FSI, renault with IDE, etc.

My previous car was a mitsubishi Galant GDI wagon. 4G64 2.4 litre, but with direct injection and high compression, huge EGR, etc. It was a nightmare to run. It produced huge amounts of carbon (decoking was a common requirement), was never smooth, went out of learn burn mode at the slightest provocation. Overall in 11000 miles I averaged 33.6mpg(imp), which as you see is barely better than the accord, despite a lighter car with fewer toys. The accord has significantly more power and much more enjoyable to drive. There are issues with many direct injection engines requiring the use of premium fuel (98/99 RON in europe) to avoid knocking, but it doesn't bring any economy benefit (I ran 4000 miles on 99RON, the rest on 95RON with that car... the 95RON was 0.2mpg better, which is within the statistical variation of the measurement). In the end, mitsubishi decided that direct injection didn't work their way with european fuel (apparently it works great in japan with ULS 100+RON), and gave up on it - all of their current lineup in europe are again port-injected. My experience with it didn't exactly warm me to it.

[CTD-Fab]

I'm back!!!!, different username though

This Is Vince and I know I have been absent from the forums for quite some time but projects have kept me pretty busy.

I do want to report that I know OWN a 2003 Civic Si with a K20A3 and i will be tuning it to the max pretty soon. My Mpgs are about 28-32 with 215-45-17 tire combo and mild to slightly aggressive driving. With Kpro I my goals are 50+

let the fun begin!!!

[bartine]

Vince

What kind of results did you get on modding your Civic Si?

I have a 2005 Si and am considering a K-series ECU reflash at $295 - quite a bit cheaper than a full K-Pro kit.

Fill us in!

Ben

[greasemonkee]

I completed a build/tune on a fellow's gsr a couple months ago. Combustion chambers were reworked/valves unshrouded and prelude injectors were used to retain decent atomization. The engine handled an impressive (for a tumble chamber) 19.5 afr before it began to misfire at a 3000 rpm cruise. I locked in closed loop at 17.5 with a .5 afr swing. As expected, less rpm required more fuel. Unfortunately, the driver pulled the vehicle from my possession before I had a chance to do further testing.