HAI Experiment

[GasSavers_NovaResource]

Originally Posted by R.I.D.E.

The wife ran regular in her Murano, which recommended premium. Not a trace of spark knock in 32 K miles. She averaged 22 MPG cpmbined on regular. Never tried Premium long enough to see if there was an improvement in mileage. EPA highway was 24, I think city was 19 (new ratings). Old ratings were 20 and 25.

Mercedes warned against using regular fuel, and had specific recommendations against using full power if you had to use regular in an emergency. That is a supercharged engine that was designed specifically for Premium.

Yes, you can run an engine designed for premium on regular fuel but the computer will cut power by retarding the ignition timing. However, loss of power and economy will occur.

Originally Posted by Jetta90GL

I guess a quick test would be to remove the knock sensor from the block to see if the power loss disappears. After all it is basically a microphone listening through the engine block material, if it cant hear, it won't retard timing.

Power loss will not disappear because the engine will be pinging reducing the power.

Originally Posted by Jetta90GL

A non-intercooled turbo engine IS a HAI, and could run with out detonation back before knock sensors where even used.

No, it was a cold air intake but the turbo heated the air. This is why boost on a non-intercooled engine is limited. Intercoolers were added to allow greater boost? Why? Because turbos heated the air and cooler intake was needed to prevent detonation. Again, hot intake air should be avoided. That's why intercoolers were added.

Originally Posted by Jetta90GL

My Turbo Coupe had a switch for regular or premium gasoline. From what I've read the premium setting caused more advanced timing and a few more PSI of boost. Premium fuel is only needed if the engine is tuned for it.

Correct.

Originally Posted by Jetta90GL

If you believe the HAI is causing ping and retarding timing, you could test the HAI detonation theory by using high octane compared to regular octane with the HAI and a comparison with out the HAI.

Higher octane would help but why would you want to spend more money on premium fuel when regular fuel with a normal intake works fine. Higher octane fuel is a band-aid fix for a WAI. Any money you save with higher mileage would be wasted on higher priced premium fuel.

Bottom line: a WAI is not a mileage improver. And it can damage your engine.
Proof:
http://www.metrompg.com/posts/wai-test.htm
http://www.gassavers.org/showthread.php?t=38
http://www.gassavers.org/showthread.php?t=396

[Jay2TheRescue]

Originally Posted by Jetta90GL

I don't think by a simple A to B test you can rule WAI or HAI a failure. Since the gains may not be a huge amount in some cases, environmental variables or even driver behavior could taint the results. Isn't the proper method to use averages of multiple trips? Seat-of-the-pants measurements don't seem very conclusive to me.

I do agree that WAI does reduce power, but that is kind of the point. Most times you don't need the full range of horsepower that an engine can produce. The manifold vacuum is reduced and becomes a savings in fuel. Try sucking on a vacuum gauge and see how hard it is to draw a vacuum.

I have felt significant power loss on my truck when I had a grill block creating a WAI. That was back before I knew anything about hypermiling, I was just trying to keep the heater warmer. I was pulling a trailer with an old POS bronco on it, and could hardly get up to speed to merge onto the highway. For this reason if i do create a permanent HAI on my truck, it will have a electric selector valve for near WOT conditions, to draw in cold air.

I'd test with your current truck. I've driven my 5.7L GMC with IAT's as high as 180F and never encountered signifigant power loss. You may find that you don't need something as fancy as that.

-Jay

[Jetta90GL]

I think your missing it all. The premium is a test, to see if there really is ping with HAI, not a solution. I can't waste my time explaining much more.

[Jetta90GL]

Originally Posted by Jay2TheRescue

I'd test with your current truck. I've driven my 5.7L GMC with IAT's as high as 180F and never encountered signifigant power loss. You may find that you don't need something as fancy as that.

-Jay

I do plan on testing it with a plain HAI, your right it probably won't make a difference during normal driving conditions. My engine is a little underpowered for how heavy my truck is, so I'd like to have some cold air for heavy towing and such.

[GasSavers_NovaResource]

Originally Posted by Jetta90GL

I think your missing it all. The premium is a test, to see if there really is ping with HAI, not a solution. I can't waste my time explaining much more.

I think you are missing it. The object is to save money. Spending extra for premium fuel is not saving money.

[R.I.D.E.]

Nova I know WAI works, I proved it to myself over many thousands of miles.

Premium fuel is a waste of money in my wifes car, she never uses the power available. As previously stated the mileage was 22 over the 32K miles she drove.

I seldom drove her car but the one example I remember was with 5 passengers at 70 MPH average speed and 25 MPG.

Timing that is retarded just enough to eliminate knock is timing that works most efficiently regardless of the engine design, as long as the engine is designed to be capable of using regular.

My cars seldom see RPM above 3000. I drive for economy almost without exception. The exception is the Mercedes when I just want to go out and play around, like the old days.

My agressive driving hot rod days ended a long time ago, about 35 years.

January I drove 1018 miles on just over 17 gallons of fuel. My 67 383 Formula S Barracuda would go exactly 170 miles on the same amount. Richard Nixon was President and the Oil Embargo had not happened until a couple of years later.

The 73 Kawasaki 900 was fun. So was the 59 Corvette. I have owned over 200 cars.

In 1984 I bought a brand new Honda CRX, and averaged 44 MPG in that car.

I have bought gas for 17.9 cents a gallon (1969). Ihave seen it for 11.9 cents a gallon (1959)

The Murano was the wifes car and she didn't want to waste the money on Premium. She bought a new Rogue (26 MPG so far) and gave her 06 Murano to her daughter after a woman ran into her daughters CRV. The wife wants her two grandchildren to be safe in the 3800 pound Murano with side air bags.

The energy content in regular fuel is the same as premium as I previously stated. There is no mileage benefit in premium in cars designed for regular's combustion properties.

Maybe one of these days I will try some premium in my Insight, but it is designed for regular.

regards
gary

[GasSavers_BEEF]

I finally found it, it took some digging.

http://www.gassavers.org/showthread....&highlight=hai

[Jay2TheRescue]

LOL, that is an old thread...

[GasSavers_NovaResource]

Originally Posted by R.I.D.E.

Nova I know WAI works, I proved it to myself over many thousands of miles.

And I've proven it does not work over many thousands of miles. So have others:
http://www.metrompg.com/posts/wai-test.htm
http://www.gassavers.org/showthread.php?t=38
http://www.gassavers.org/showthread.php?t=396

[GasSavers_BEEF]

distance:263
fuel used:11.566

thousands of miles????

jay,

I remembered starting a similar thread way back and thought I could add some positive info to this very negative and heated topic. I went into looking at the WAI with a non-biased attitude and if it didn't work for mine, oh well. luckily for me, it did work...at least for my application.

I'm not so quick to call something a failure or to go as far as to add a bunch of mess to my signature of all of this. it makes me wonder why others care so much and quite frankly, why they are here in the first place