I messed with a WAI mod yesterday on my 06 Civic EX Sedan, 5MT, w/Navi. The car is well ran in with around 11k miles on it to date. Its driven to work some days, putters around town and has been driven from the Tulsa metro area to PHX, Az. Its seen its share of redline shifts, Wheels spun and ABS action. After all it is a Civic.
Its worse tank was 29 mpg, its best has been 47 mpg 25c/75h.
I have used WAI to improve FE in older big block and small block v8's in years past and some I6 engines. Always seemed to be good for about a 2 mpg increase across the board. These being carb motors it always took a major retune to see these results. Including, timeing change, cooler thermostat, idle air adjustments and higher octain fuel.
So armed with knowledge from the past and knowing there wont be any retuning for this run of test I go down to the local O,rilleys and purchase WAI alum hose commonly used on our old trusty v8's and I6's from years past. Cost $3.00 and some change.
This is a very complex install. Takes all of 30 secs. I opened the hood, yanked off the OEM rubber intake duct. Cramed it down and away from the filter box. Yanked on the alum. flex duct to increase its length. Pushed one end of the hose into the opening in the filter box, fourmed the hose around and set it next to the massive CAT right off the head and lodged in next to what acts like a exhaust manifold. Done! Ok it took a 1 min. sorry.
The R18a motor in the new Civics dont have a exhaust manifold so to speak. Its all cast into the head. So they are very short passages if you will straight to a CAT.
My first run was with the WAI installed. Air temp was 95f. (was hot here in Okiehoma yesterday) Car warmed up in a flash. I set out one of my test loops around here. This is a 20 mile run thru my small town out to a hwy and back. Intake air temp with the WAI was 141F any time the car was moving up to 150f if the engine was off or at idle. I ran the loop came back, pulled the WAI slapped the OEM hose back on and did it again. OEM unit air temp was 101f with car moving and didnr flucuate much one way or the other. Then came back after that loop run and pulled the OEM duct off again and ran the loop with the filter box open to under the hood air temps. Max. temp in this mode was 121F on the hwy and it did flucuate alot.
I worked on this from the afternoon hours to early in the morning. I logged around 120 miles doing these test. As for night temp's. Just subtract 20f off the day time temps.
From all these runs and configs on the intake. I saw a soild 1 mpg increase in FE with the WAI. I had no pinging, water temps stayed the same. I didnt ever wrap the tach up. But I felt no loss in power in the range of 650 rpm to 3k rpm. I used my ScanGauge to look at the temps, mpg, timing and such.
Im going to leave the WAI on for awhile and see what it does. Im going to keep a very close eye on it. My guts telling me this may be a winter only mod and that I may end up running the inlet open to the air under the hood for summer. And then run the OEM CAI when I want to play. I do like to tackle the twistys from time to time. Theres always somebody that needs to be imbaressed by a little stock Civic from time to time.
It was a intresting test and there is something there to be had. Is it worth it and will the ECU with time adjust its self better for the mod. Only time will tell.
Theres alot going on in a r18a engine. Its not fully understood yet. The semi atkins low rpm head function. The normal function and then vtec.
I dont know as of yet if when the engine is in low rpm idle to 3k rpm if the amount of fuel injected is less than a normal cycle or is it all in valve/cam timings that allow for the so called 1.5L compression stroke to happen. Is it chargeing the cyclinder like a 1.8L and then pumping some of the charge back into the intake manifold? Is there a lean burn component in this action? Theres alot to learn here.
Im not the best hypermiler. I have the skillz but tend to get lazy sometimes. That and I enjoy many driving styles. I do use low rpm shifting, steady foot, DWL, FAS, coast, light timing, engine off at light, will draft and surf also ride ridge in rain or follow trails.
My lmpg is at 39.6 with my high tank at 47 mpg, low at 29 mpg. OOO and the wife has never driven the car.
Hope this mess was a good read and that there maybe some useful info here.
psy
PS,,, we really need more 8th gen Civics in the game. I havent found a sole yet working with a non-hybrid Civic yet.
Im uploading a video of the last run I made at about 1am this morning. It nothing but 29 miles of the ScanGauge with the WAI installed. Its over 200 meg @ 640x480. Will post a link here when its done.
Linear Mode
