It's been darn cold here... (cai delete + grille block)

[wdb]

...and my Honda Fit doesn't much like it.

It doesn't do anything particularly bad; it just takes a very long time to warm up, and the gas mileage turns to poo. So I decided to try ridding the car of its factory CAI and adding a grille block, in the hopes of improving both at least a little bit.

Under the hood, I pulled the rubber accordion thingie off the air cleaner inlet, disconnected the other end from the inner fender, and removed it from the car. Then I plugged up the hole in the inner fender where the cold air comes in. No big deal.

Next I fashioned a lower grille block out of plexiglas and tiewrapped it in place. Pretty simple! It's a straight-up rectangle, easy as pie to measure and cut. I even used a $1 castoff piece of plexi from the local hardware store. I was starting to feel very, errr, ecomodder-ish.

I went for a little drive, and lo and behold the car warmed up noticeably faster. Yay! But my joy was shortlived.

Intake air temps were up too, but only about 5 deg F. Boo. I guess I'll have to go back to the hardware store and get some tubing to pull air from the backside of the engine.

The next day I went for a longer drive. Immediately upon getting up to freeway speed the water temperature ran straight up to 215+ deg F and the electric fans came on. The temp dropped, the fans turned off, and the cycle repeated. Double boo! I pulled over, snipped the tiewraps, and removed the grille block. Temps returned to reasonable levels.

Looks I need to make some holes in the grille block. No big deal, I have a bunch of hole saws and whatnot from various projects. As I started to make the first hole, the pilot drill bit snagged on its way out of the plexi and shattered it into 3 pieces. Triple boo.

Sigh. It seems like most stuff I touch lately gets worse instead of better.

Maybe I should sit in a chair, watch TV, drink Dogfish Head stout, and wait until my biorhythms get out of their funk.

[Thymeclock]

The next day I went for a longer drive. Immediately upon getting up to freeway speed the water temperature ran straight up to 215+ deg F and the electric fans came on. The temp dropped, the fans turned off, and the cycle repeated. Double boo! I pulled over, snipped the tiewraps, and removed the grille block. Temps returned to reasonable levels.

So - what's the concern? If it were summer and it were 90+ degrees, the fans would do the same and cool the radiator, wouldn't they?

It's all about ambient temperature and the type of driving you do. If you are typically driving one mile at freezing temps and then shutting the car off (as is my situation daily), you will need a full radiator block just to reach operating temp slightly faster than usual. OTOH, if you are driving more than 1/2 hour at mostly highway speeds, it may tend to get a bit hot.

Consider making a radiator block that is easily removable. I recently realized that I could do this with my '89 Galant in sliding two pieces of thin formica panels in front of the radiator that stay there requiring no other effort. It takes me all of ten seconds to remove them if necessary. But, seeing that I'm always freezing my ass off in the car in winter, I don't mind it being on the hot side.

[wdb]

I was not trying to do much with the grille block besides improving warmup times. A bit higher operating temperature would be acceptable, but I was not intending to make the engine run so hot that the electric fans came on. That sounds like a pretty inefficient way of doing things to me.

Eh. I'm just in a funk because I broke my new toy and have to make another one.

[Thymeclock]

Originally Posted by wdb

I was not trying to do much with the grille block besides improving warmup times. A bit higher operating temperature would be acceptable, but I was not intending to make the engine run so hot that the electric fans came on. That sounds like a pretty inefficient way of doing things to me.

Eh. I'm just in a funk because I broke my new toy and have to make another one.

But even in winter, the fans still come on when needed, right?

In a perfect world, the ambient temp would be such that your car wouldn't need any cooling fan(s). (Hmm. But in a perfect world, we wouldn't need cars...)

[bgd73]

at least the fit has the extra heat from injection. I went through this same routine on a1781cc carbed engine. Best bet, lo and behold, was no grill block, even bigger air from the factory design. I went backwards for quite some time.
I ponder a real cheap solution, after breaking the element in my oven, and realizing it keeps working in pieces (cool) and making something safe and hot with a 20 dollar 400w invertor...it is so close to beng normal below single digits F, yet so far away...
Little engines suffer. Inlines do have it better than boxers...boxers throw it all away ..
the problem with winter is mileage, it absolutely has to take more in to get to thermal efficient, no getting out of this. I tried shallow localizing heat, and it is the same routine as you went through, best bet is to let it go. When it does reach the real wot, it is the larger one, and hangs on for the ride, and even shutting down intermittently hangs on better.
shallow localizing, cools it down faster, and is a waste of time, and hot oil and bearings and gaskets and...

[FastPlastic]

Originally Posted by wdb

I was not trying to do much with the grille block besides improving warmup times. A bit higher operating temperature would be acceptable, but I was not intending to make the engine run so hot that the electric fans came on. That sounds like a pretty inefficient way of doing things to me.

Eh. I'm just in a funk because I broke my new toy and have to make another one.

You are right in thinking the grill block was too much. The electric fan on a car is a major power draw(Volts * amps = Poor Mileage) don't get discouraged. You just found the point that is too much. Try opening it up a ways to give it a little air. Leave yourself a good 4-8sq in for starters and you'll see much better results. On my Jeep I've found 4 out of the 7 grill slots is a happy medium.

[jmf]

Could you pull your intake air thru the radiator?

[jamesqf]

Why not just make the block smaller? With the Insight, I have a couple of different sized pieces of coroplast that I slip between the radiator and A/C radiator, and change according to season & terrain. When I go over the mountains in spring & fall, I take the block out when going up, then stop at the summit and put a full block in, since I can basic coast all the way to the bottom.

[brucepick]

Do your grill block experiments with cardboard or stuff bits of pipe insulation between the slots (my current method) or coroplast. This makes it easier to change your mind and experiment.

I find I gradually need to add more blocking as deep winter sets in, and gradually remove it as things warm up in spring. I'm seeing coolant temp on the ScanGauge so I can tell what's going on. People with just a simple gauge are at a disadvantage on this.

[MadisonMPG]

Originally Posted by Thymeclock

It's all about ambient temperature and the type of driving you do. If you are typically driving one mile at freezing temps and then shutting the car off (as is my situation daily), you will need a full radiator block just to reach operating temp slightly faster than usual. OTOH, if you are driving more than 1/2 hour at mostly highway speeds, it may tend to get a bit hot.

Depending on your health, you should try to cycle. 1 mile is super easy on a bike. I did a mile in 8 minutes, and that was taking my time. I mean, barely pedaling.