Altima Cold air intake - Fuel Economy, Hypermiling, EcoModding News and Forum

99clipsgst · 10-12-2011, 02:57 PM

I have created a cold air intake on my 07 Altima 3.5se. I took a weapon R intake with the filter heat shield and attached a flexable spectra tubing. Before I did this I just had the intake and no cover on the filter. With my Ultra guuage the intake temps whereer around 119 -124F sitting in traffic. Now the temps avg around 104-106F. Let me know what you guys think. Since i took these pictures I have wrapped the upper intake pipe in heat reflective insullation.

Here is what it looks like underneath.

Front bumper

http://www.youtube.com/watch?v=9jT8P...layer_embedded

CigaR007 · 10-12-2011, 03:24 PM

The tube opening is sitting rather low and exposed to the elements. Just make sure that water does not get past the filter, as it could result in hydrolock, and possibly ruin your engine.

99clipsgst · 10-12-2011, 03:38 PM

I have drilled a few small drain holes into the lower part of the tubing. Also the heat shield that goes around the filter has a some space for the water before the filter starts sucking water. Being in FL I have been in quite a few storms and the holes I put on the bottom really help.

MPGranger · 10-12-2011, 04:20 PM

Any testing for MPG improvements?

99clipsgst · 10-13-2011, 12:47 PM

I have seen an increase in MPG but with the weather cooling down its hard to tell if the change is from no a/c or this intake mod. Right now I'm trying to find a way to make a air dam that is only a few inches long.

California98Civic · 10-13-2011, 01:58 PM

If you are still seeing intake air temps 106-110* even though the air is being pulled directly from outside, idle in traffic, I guess the filter housing and tubing are getting hot and warming the air. Either that or it is wicked-hot in FLA right now (maybe). Did insulating the tubing help? Anything further you can do for the filter housing itself?

jkv357 · 10-13-2011, 02:06 PM

Looks good, but isn't hot air better than cold air for maximum MPG?

Cold air makes more power because of higher air density, but also requires more fuel to balance the increased air density - right?

Somebody fill me in here...

tjts1 · 10-13-2011, 02:18 PM

Cold air is definitely the way to go. Hot air will cause the engine to pull timing and increase consumption.

Daox · 10-13-2011, 03:25 PM

You can't say warm or cold air is better and have that be that. It is completely dependant on engine design and programming. However, warm air is generally better for fuel efficiency. It is less dense, so it requires a larger throttle opening for the same amount of power. A larger throttle opening reduces pumping losses and increases BSFC. Warmer air also speeds combustion which also increases efficiency. If you go too warm (again totally dependant on what engine you have), you can may run into issues with retarding timing. However, switching to a higher octane fuel would remedy that issue. Most cars love 100+F air, they start getting quirky around 140F from what I've read (again it differs from engine to engine).

oil pan 4 · 10-13-2011, 04:15 PM

You always want your ram air and cold air intakes to go up hill like that.
The intake on my truck is low, but not that low and it picks up plenty of dirt.
I need to get a CAI for the car the constantly changing under hood temps are making my air/fuel ratio jump around a lot.