2002 Honda Civic Coupe LX 5spd Build Thread

[Christian]

Here are photos of the coroplast lower grille block fitted on the civic.
Turns out I screwed up one of the zip tie mounting spots, so there is a ~1in gap on the edge of the grille block. To fix this, I jammed some pipe insulation in there. I will eventually fix it, but for now, my goal is to see how well the grille block works and decide on which changes can be made to improve the next version.

[Tmugz88]

I'm new here but wouldn't leaving an opening like you did negate the purpose of the grill block? No disrespect towards you I honestly am asking a question because I truthfully don't understand how this would improve aerodynamics enough to justify the work. Could you do a full block and utilize the pipe insulation as a spacer to allow some air to enter/exit ?

[Ecky]

Originally Posted by Tmugz88

I'm new here but wouldn't leaving an opening like you did negate the purpose of the grill block? No disrespect towards you I honestly am asking a question because I truthfully don't understand how this would improve aerodynamics enough to justify the work. Could you do a full block and utilize the pipe insulation as a spacer to allow some air to enter/exit ?

Even a partial block helps - you end up with a high pressure zone and most of the air goes around or over the car, rather than through the aerodynamically very dirty engine bay, then out the bottom (or wheel wells). More importantly, it helps reduce warmup times.

[Christian]

Originally Posted by Tmugz88

I'm new here but wouldn't leaving an opening like you did negate the purpose of the grill block? No disrespect towards you I honestly am asking a question because I truthfully don't understand how this would improve aerodynamics enough to justify the work. Could you do a full block and utilize the pipe insulation as a spacer to allow some air to enter/exit ?

I believe you're right, it definitely seems like it would have a poor effect on aerodynamics. I can't really speak on exactly how much of a negative impact it would make though.

However, my goal for the mod is to increase the warm-up time of the vehicle, not improve aerodynamics. The large majority of my driving is short stop & go city trips. I plan on also building an upper grille block eventually to help increase the temperature of air coming through the intake.

[EcoCivic]

Originally Posted by Christian

I believe you're right, it definitely seems like it would have a poor effect on aerodynamics. I can't really speak on exactly how much of a negative impact it would make though.

However, my goal for the mod is to increase the warm-up time of the vehicle, not improve aerodynamics. The large majority of my driving is short stop & go city trips. I plan on also building an upper grille block eventually to help increase the temperature of air coming through the intake.

If your goal is to increase intake air temperature, I'd start by removing the resonator box. This will certainly increase your IAT a bit since you will be pulling air from much closer to the engine and the intake will see more radiator heat. This will also make a lot more room in the engine compartment and save a few pounds, all good things.

I wouldn't expect huge gains from higher IATs, I have changed my intake configuration several times trying to get the coldest air possible for improved performance and I never noticed my fuel efficiency change with IAT. I do plan on eventually experimenting with using a small heat exchanger to warm the fuel going to the rail with coolant though, I'd think warmer fuel could improve cold weather efficiency by vaporizing easier but we will see.

Does anyone have any data on what the ideal IAT for fuel efficiency is in their application? Too cold would theoretically hurt efficiency by increasing pumping losses and not vaporizing fuel as well, but too hot will result in the ECU retarding ignition timing and possible knock, which isn't good either.

[Ecky]

I seem to recall someone quantifying ~130F as being where their fuel economy peaked. I saw large improvements with a warm air intake during Vermont winters, but some days the air temperature was -10F or lower, so we're talking a 140F+ increase. That's a lot of extra energy being put back into the cylinders.

Go too hot, and most ECUs will begin to retard timing to protect from detonation.

[Christian]

Well, it's been a few months since my last update, but there wasn't a whole lot to talk about in regards to the car, it has become less of a "city civic" and more of my highway commuter. My commute has changed and I am now driving about 50 kilometres on the highway per day instead of 5 kilometres in the city per day. This is quite a drastic change, which is reflected in the jump in my fuel usage and the massive improvement in fuel economy you can see starting in May of my fuel log.

This new commute isn't terrible, but my drive home every day is usually in traffic, so I am not hitting amazing numbers. However, in my last tank, I have just beat the civic's EPA highway rating, which is 36 mpg. My last tank was 6.02L/100km which is 39.07 mpg. My Scangauge II is also finally getting dialled in, on that last tank, it was predicting 5.9L/100km.

Other than my change in commute, the only news on the Civic is that I finally put on the lightweight Mini Cooper R81 Imola wheels that I previously posted about. These wheels probably helped me a decent bit in hitting 39 mpg in my last tank, thanks to the reduction of rotating weight, but I can't be too sure, as I didn't establish many baseline tanks with my new commute on my steel rims. The wheels weigh 11.9 lbs each and are wrapped in Goodyear Assurance 175/65/R15 tires inflated to 42psi.

Side note, I also recently purchased a 1999 Ford Ranger XL 4x4 with a 3.0L V6 and 5spd manual. I purchased the vehicle at 175,121 kilometres (108,815 miles) for $2000 CAD ($1481 USD). I'm not driving the truck very much right now, but I added it to my vehicle list and will track the fuel mileage once I start driving it a bit more.

Attached below are photos of my new wheels and my new ranger.

[ME_Andy]

Sounds like a great deal on the Ranger! Wish I could find a deal like that

[Christian]

Well, it's been just under 5 months since my last post, so I figured I'd make a short update. The car has been doing great, my current 3-tank fuel economy and 90-day fuel economy are both 5.7L/100km (or 41.4mpg).

Since my last update in May, my worst fuel economy has been 6.5L/100km (36.2mpg) and my best was 5.2L/100km (45.2mpg). I am really happy with these numbers, especially since the car is only rated for 6.5L/100km (36mpg) on the highway. However, my commute will now involve more city driving once again, so I expect my fuel economy to begin dropping again.

Unfortunately, I hydroplaned last month on my way to work and smacked a curb pretty hard. Fortunately, I was unharmed and able to drive the car into a parking lot and get it towed. The lower control arm and sway bar were replaced, and other than some cosmetic damage to the wheel, the car is back to its previous state.

Attached below are photos following the accident. If you look closely at the first image, you can see the wheel has a positive camber, and in the second image, you can see why.