Black & Green modding thread (1998 Civic DX Coupe base)

[jeff88]

How long do you have to wait to see the 40+ rise over ambient? Do you have to wait until the engine is fully warmed up (at least according to the in-dash gauge), or does the exhaust heat give you warm air sooner?

[California98Civic]

It has to warm up, but I am not certain for how long. My guess is quite a while past accomplishing simple running temp. I think heat needs to build up in the associated parts, like the heat shield, the valve cover, and maybe especially the tube itself, which is a typically thick walled ABS plastic pipe.

EDIT: it helps that I have the grill block and ducting, so that the only air coming into the engine area goes first through the rad.

[California98Civic]

WAI readings for end of 11 mile morning commute:
50 degrees ambient, 93 degrees IAT (1/27) +43
57 degrees ambient, 102 degrees IAT (1/26) +45
44 degrees ambient, 86 degrees IAT (1/23) +42
44 degrees ambient, 87 degrees IAT (1/22) +43
55 degrees ambient, 95 degrees IAT (1/21) +40
58 degrees ambient, 100 degrees IAT (1/20) +42

AND on a 60 mile freeway drive the other day with ambient temps in the low sixties I was at IAT 116+ after about 15 miles. Temps stayed 50+ degrees above ambient, rising as ambient temps rose, throughout the drive.

[Xist]

I have also linked that rolled plastic. I use it as a grill block and air dam, but I need to reinforce the back, it must deform fairly easily. I saw something on here about putting black caulk on the edges and was going to try that, but then thought that it would be a bad idea, since I still need to remove it at least once.

[California98Civic]

Originally Posted by Xist

I have also linked that rolled plastic. I use it as a grill block and air dam, but I need to reinforce the back, it must deform fairly easily. I saw something on here about putting black caulk on the edges and was going to try that, but then thought that it would be a bad idea, since I still need to remove it at least once.

I have seen something more like "re-forming" (rather than "deforming") back to the curves it had when it came as a roll. I am considering the heat gun for that. I am also thinking of reinforcement, but yesterday i rolled the skirt giving trouble and braced it to hold for hours. I'll soon see what it looks like this a.m. when I leave for work.

[California98Civic]

So, ever since installing the new WAI and getting markedly higher 40-50 degrees over ambient temps on the intake sensor, I have noticed long term fuel trim greatly leaned-out, as in this photo. I also think I can feel less power in certain routine situations. Oddly, conventional wisdom here has been that the ECU will keep stoich and that gains come from reduced pumping losses. I still think the pumping losses idea makes sense, but my UG is telling me I am running far leaner than I used to. Normally, this long term fuel trim would read +0.78, now it generally reads -6.2 and leaner.

Why, do you think?

[Baltothewolf]

Originally Posted by California98Civic

So, ever since installing the new WAI and getting markedly higher 40-50 degrees over ambient temps on the intake sensor, I have noticed long term fuel trim greatly leaned-out, as in this photo. I also think I can feel less power in certain routine situations. Oddly, conventional wisdom here has been that the ECU will keep stoich and that gains come from reduced pumping losses. I still think the pumping losses idea makes sense, but my UG is telling me I am running far leaner than I used to. Normally, this long term fuel trim would read +0.78, now it generally reads -6.2 and leaner.

Why, do you think?

Warmer air is less dense = less fuel to bring it to 14:1 afr, as a result, less power due to less fuel consumption. That's why cold air intakes give more power. Colder air = more dense = more fuel to keep it at 14:1, as a result, more power due to more fuel consumption.

[Edit]: Why is your engine temp at 122F?

[California98Civic]

Originally Posted by Baltothewolf

Warmer air is less dense = less fuel to bring it to 14:1 afr, as a result, less power due to less fuel consumption. That's why cold air intakes give more power. Colder air = more dense = more fuel to keep it at 14:1, as a result, more power due to more fuel consumption.

[Edit]: Why is your engine temp at 122F?

Yes, but in numerous discussions on EM that position has been debated, with the argument being that the ECU will compensate. But here, my UG is suggesting that the ECU is not compensating. That I am running lean, consistently. That surprises me, and I am wondering why it is so, or if I am misunderstanding the meaning of this display. ... the coolant temp is low because the car had been sitting for over an hour after running...

[Baltothewolf]

Originally Posted by California98Civic

Yes, but in numerous discussions on EM that position has been debated, with the argument being that the ECU will compensate. But here, my UG is suggesting that the ECU is not compensating. That I am running lean, consistently. That surprises me, and I am wondering why it is so, or if I am misunderstanding the meaning of this display. ... the coolant temp is low because the car had been sitting for over an hour after running...

I'm not sure why people would debate that. It's a proven science. The ECU may compensate a little bit, but it's designed to run at 14:1, regardless of what your intake temps are. So when you have less dense air and the ECU detects that you are running too rich, it will automatically drop fuel consumption. It's NOT changing the overall air/fuel ratio, just how much actual fuel is required to keep the desired 14:1. It's like human fat. You can be really fat and look huge, but you can also have someone that's skinny that weights the same if he is all muscle. Why? Because muscle is denser than fat. Warm air = fat, cold air = muscle.

[j12piprius]

What were your average mpg and mph?

Did using the WAI improve your average mpg?