HAI Experiment

[Jay2TheRescue]

Originally Posted by BEEF

that does have an advantage over the DIY kind. doesn't it close off at WOT. that way you can have your cake and eat it too.

power when needed.

that is one thing I have missed. when some yahoo comes flying up on me. he goes to pass. I don't have a chance (like I really had a chance before.lol)

Under WOT, and vacuum drops, you don't have enough vacuum pressure to keep the trap door closed, so it opens letting colder air into the engine, so yeah...

[GasSavers_NovaResource]

Originally Posted by Jay2TheRescue

Yes it has been installed by automotive engineers... My 1981 Buick (O2 sensor & computer controlled) and my 1986 Chevy truck (Not computer controlled) both have WAI from the factory... Plus my old 1980 Bonneville, my 1974 Chevy truck, and my 1981 AMC Spirit all had WAI from the factory. The only vehicle that I have ever owned that didn't have it is my 1998 GMC truck.

-Jay

Only when the engine is cold does that valve direct warm air off the exhaust. It's done to help the engine warm up quicker. Once the engine gets to operating temperature, the valve switched over to cold air.

If you check your car you will see the vacuum line from the valve goes to a thermostatically controlled vacuum stitch. Only when the engine coolant is cold does engine vacuum pull the warm air intake valve open.

[GasSavers_NovaResource]

Originally Posted by BEEF

jay,

don't discredit his findings, it took him 3 hours to dig up that snipit of data. you shouldn't correct him in a mere 5 minutes.

I guess the search continues.

And that's not insulting me?

[GasSavers_maximilian]

If the WAI does happen to work for my car, maybe I'll put a valve in to switch to cold air for when I'm towing my trailer. Getting a bit crowded under the hood...

[Jay2TheRescue]

Oh yeah, disconnect it when towing... WAI works best when running the engine under low load conditions where you don't need full power.

-Jay

[GasSavers_BEEF]

jay,

so the vacuum holds the door closed and the thermostat opens and closes (varies) in order to keep the air temp at a predetermined temp. I like that. it really is the best of both worlds.

you could further heighten the affects if you could change the thermostat in order to increase the temps more but then you would have to retune the carb for that. I saw a buddy of mine do that to his chevette. it was not a fun experience. he plans on fuel injecting it soon so he didn't put a lot of effort into it.

[Jay2TheRescue]

I just got a PM from another member that pointed out that the factory WAI helped prevent the carb from icing up due to the venturi effect cooling in the throttle body.

[GasSavers_NovaResource]

Originally Posted by Jay2TheRescue

I just got a PM from another member that pointed out that the factory WAI helped prevent the carb from icing up due to the venturi effect cooling in the throttle body.

Yes, that is true. And it's also why modern fuel injected engines have engine coolant running through the throttle body. Not to cool the TB but to warm it to prevent icing.

[R.I.D.E.]

Todays drive;

Exact same route as yesterday.

Ambient temps identical.

Wind practically non existent, where yesterday it was a 15-20 MPH help on the first half.

No direct WAI, but a 40 % radiator block. Incidentally the Insight draws its air from behind the radiator, so it has factory WAI if you want to call it that.

Yesterdays average was 74.7 MPG. I did not include the initial warm up in yesterdays trip on purpose.

Total distance for both trips with combined mileage for both days.

73.3 MPG for both days

Yesterdays average

74.7 MPG for the identical trip without the initial warm up, which was included in todays trip. Two 1 hour cool down cycles at the trip mid point.

Difference in mileage

1.4 MPG

Total fuel use

784/733 gallon=73.3 MPG for 78.4 miles

The return trip today was affected by three traffic lights that caught me on the yellow light and forced me to waste my inertia. I estimate that alone caused me to loose 1 MPG for the combined two days of travel.

In fact the cost of the three forced stops was greater than any individual warm up cycle.

Look at the first half of yesterdays trip to see the difference in mileage due to the tailwind on the first half and headwind on the second.

Much greater than the cost of the second days additional warm up cycle.

WAI behind the radiator works under light loads, but the amount of air inducted at higher throttle positions rapidly removes the heat available and gives you colder air automatically under sustained hogher throttle positions.

That is the way my insight was designed, and it still is the mileage champ of any automatic transmission vehicle ever sold in the US.

The hotter the air you induct the lower your effective compression at WOT.
Cold air for performance gives you the best horsepower. Warmer air gives you the best efficiency.

Ignition timing is automatically adjusted to most advanced point the engine can handle without preignition, the sensors are much more sensitive than the human ear, in vehicles equipped with knock sensors.

To assume that warmer air causes higher NOX emissions just doesn't hold water as a logical argument. Peak combustion temperatures are a function of the power produced by an engine, which also causes preignition. Less dense warmer air creates better fuel atomization as well as slightly lower compression as well as lower pumping losses.

Manufacturers choose more power because most customers want more power. That sells cars.

When the public demand as well as federal regulations demand better mileage, then manufacturers will produce what sells.

Warmer return coolant to the engine is a factor in improved summertime mileage, as well as warmer air intake.

Any one who has driven a performance car knows the power is greater in winter than in summer, and correspondingly the mileage is lower.

Alfa Romeo built a 90 cubic inch grand prix racer that produced 390 HP in 1950, the year I was born. It got 2 MPG.

How much fuel does a top fuel dragster consume in a single pass?

Gallons.

Economy versus power is the trade off. If you want power, the price is mileage. Choose one or the other.

Given the same fuel to air ratio, more fuel and more air equals more power.
The problem is 67% of your fuel energy is wasted (EPA data) so more power means less economy.

I believe the Toyota Prius is the only car they make with the thermos bottle to hold hot water for the next cold start. My buddy replaced one in a wrecked Prius he repaired. The part costs $1000 retail. I was thinking about using the damaged on on my car, but the damage was to severe to trust it.

Getting great mileage in any car involves a lot of small factors that add up to a total improvement. My car is rated at about 46 MPG average (new ratings). The old ratings were 56 highway and 57 city, on fuel that did not contain ethanol. All the fuel where I live contains ethanol, so there is a disadvantage in any direct comparison with non ethanol fuel.

All that being said, the greatest part of my significantly higher average mileage is in driving style. Unlike some members, my priority is fuel mileage above all else. Comparing one percentage over EPA to any other is irrelevant unless the mileage acjieved is under identical circumstances. If I lived in a sparsely populated area without traffic lights and I could drive at any speed I chose I could get 90 MPG average, but I am in no hurry to get anywhere. Retired from the rat race I see no point in voulentarily joining it unless it is an emergency. In those circumstances I would just grab the Benz.

Gains of super high percentages over EPA require great determination and discipline as well as sacrificing time for saving money on fuel. The cumulative effects of the efforts of the members of this forum is to provide real innovation and empirical evidence to show people who are interested how to screw OPEC.

If my Insight was a manual transmission I could top 120 MPG under ideal circumstances. I just don't want to trade off my situational awareness for the difference in mileage.

Thats dangerous when you are surrounded by people who drive like idiots.

regards
gary

[GasSavers_maximilian]

Originally Posted by R.I.D.E.

To assume that warmer air causes higher NOX emissions just doesn't hold water as a logical argument.

That's weird, I thought you were the one who said it might raise them. I must've misremembered. Too lazy to search and it'd be pointless anyway.