HAI Experiment

[R.I.D.E.]

On the topic of Diesel engines. Many do not operate on the Otto cycle.

Examples:
OPOC
Detroit 2 strokes
Free piston engines

In the classic definition of the first functional Diesel engine. Rudolf Diesel developed high pressure timed injection as a solution to the problems related with the early gasoline engines as to how to deliver the fuel and ignite that same fuel in a reliable way without destroying the engine. Even spark plugs were in their infancy as far as reliable ignition amd durability. Compression ignition eliminated the spark plug issue altogether. If memory serves me correctly Mercedes produced the first practical Diesel powered automobile in 1936.

Rudolf's original design used peanut oil as a fuel, which did not have the sulfer content problems associated with modern oil based fuels in todays diesel engines. Rudolf Diesel, the inventor of the engine that carries his name died a poor man. With modern biofuels many of the sulfer related Diesel emission issues are resolved by changing the fuel source itself, which has been most of the problem all along. Recent legislation has also required significant reductions in the sulfer content of Diesel fuel.

While compression ignition is generally associated with Diesel engines, in HCCI engines it becomes practical because the issue of fuel distribution in the combustible fuel air mixture is resolved by achieving a truly homogenous mixture at the molecular level. This means when ignition occurs, it occurs everywhere in the combustion chamber at the same instant, whcih is not the case in a traditional diesel engine, or in any non HCCI gasoline engine. Spark knock in as conventionally understood is only present in HCCI engines when the compression induced ignition occurs before TDC on the compression-combustion phase of the cycle. This issue is being addressed, as we speak, by developing a means of variable compression ratios. My engine design allows for compression ratios to be varied from 0 to as high as 50 to 1. In this design the point of combustion is controlled by the compression ratio itself. A conventional knock sensor would be utilized to reduce the compression ratio to control the point of ignition to occur exactly at the same point, relative to TDC, regardless of load changes on the power output of the engine itself. Generally speaking compression ratios would be lower as load became higher, an essential component of successful HCCI implementation. Another essential component of successful HCCI is to have a precisely predictable load scenario. This is not practical with engines as the yare currently used in vehicles, due to the changes in effective compression due to throttle restriction being utilized to control power output. In future designs HCCI engines will always operate without any manifold vacuum present, which achieves highest effective compression. In other words you will change the compression ratio of the engine, instead of restricting the airflow to reduce engine power.

Although most HCCI developments are in the field of Otto cycle (4 stroke) reciprocating engines, there are developements in engine designs that are not 4 stroke engines. I have one such design. Another is the free piston design. In one case the Free piston design is combined with a linear generator to recharge barrteries in an electric hybrid. Another is OPOC, but I am not sure if it will every be configured for HCCI becasue that design uses 2 crankshafts and opposed pistons which increases reciprocating mass beyond conventional reciprocating engines.

In other designs the Free Piston engine develops hydraulic pressure directly for a hydraulic hybrid vehicle. The vehicle is driven by hydraulic fluid from the accumulator with no direct connection to the engine itself.

Google Ingo Valentin of Valentin Technologies for a good read on his hydraulic hybrid if you are interested.

Regardless of the engines specific cycle the practical development of a functional HCCI engine has the additional benefit of potentially eliminating the necessity of pre or post combustion emission treatment on top of improved energy conversion efficiency. No more catalytic converters.

Nova
Your reference to the 2001 article on Premium and regular fuel requirements mirrors my experience with my 3 vehicles.

I am not interested in discrediting you. I am here to learn (which I have considerably) and to try to inform people of my designs as well as the developemnts of others which should lead us to the point where we no longer depend on OPEC for oil, and the resulting reductions in global emissions that would be an additional benefit of reducing fuel consumption in every vehicle on the planet.

Sit back read and enjoy. I hope you find information that provides you with a direct financial benefit, as well as an environment that is capable of sustaining the lives of those who have no means to really change the way we drive and live. Lets hope we leave the young and innocent a world that is better then the one we inherited.

Try our suggestions yourself. Some will work. Some will not work. What works for you does not determine what works for me. I know what works for me and that does not determine what works for you.

Thats the difference between a personal conflict and some benefit to all. What you may or may not achieve is totally under your control.

Good luck and I hope you succeed. I have already.

regards
gary

[theholycow]

More data: Here's a gaslog I didn't see before...user Project84's Saturn SL2.
http://www.gassavers.org/garage/viewgaslog/1083

13 tank (December through June) average before HAI, not including his first logged tank which was abnormally low (22.46mpg) or one other that was abnormally low (21.84): 26.6mpg

18 tank (June through March) average after HAI, not including one abnormally high (43.66): 32mpg.

If I put back in the extreme tanks that were removed, the spread increases: 26mpg vs 32.7mpg.

If I take out summer data from the post-HAI tanks and just use 10 tanks from October through March, it's still at 31.23mpg.

No matter how I slice it, I can't deny that Project84 has real results. He has saved gas after the HAI that he didn't save before it. That's way better data than ANY of the sources cited in the argument that HAI can't work on any car.

Nobody's trying to say that it would work for everybody...just that it works for some.

[Project84]

This makes me smile. I had forgotten about this site on purpose because of my recent poor gas mileage and lack of enthusiasm for attempting to save gas... my rings are shot (or at least, they've got 1 foot out the door).

But I just signed back in the other day and posted about someone's SL2, advising him to add a HAI... now today I'm getting a big thumbs up of gas saving when I'm least expecting it.


Truth is, my HAI cost me about $12 and paid for itself within a month, ever since then I'm saving gas. Even now, when my numbers are slowly lowering because of my engine about to need an overhaul, I'm more than willing to bet if I took the HAI off I'd drop 3 or 4 MPG on my next fillup.

Lets keep in mind the HAI is my only mod other than my ScanGaugeII. Hell, I haven't even checked tire psi in 6 months. I do not P&G, EOC, or any other acronym. lol I literally just DRIVE, and try to "smart brake" when I remember to.

EDIT: I also never completed any insulating as has been discussed by other members, which will increase IAT's even more. Mine is a VERY savage design. Some flashing as a heat shield, dryer ducting for an intake, and it's got a hose clamp on a 90* PVC plumbing fitting just hanging out of the bottom of the airbox. I'd say if I'm lucky I'm only getting about 60% hot air into the intake, the rest is going to be engine bay air/fresh air. Intake temps rarely get above 150*F, and that's on the HOTTEST of summer days. It's been tested and found beneficial to reach 170-180*F in the Saturn S-Series. I've never seen temps that high. I can only imagine if I did get 170-180, I'd be saving even more gas (although there is a lack of engine power at those temps, and I've heard emissions #'s get ugly)

[bowtieguy]

john,

do you have any plans for engine swap or overhaul?

[101mpg]

It's nice to see some more real-world data. HAI does work on many vehicles. Due to the design, it does not work for some vehicles.

I remember a Mythbusters episode where they tried to discredit driving with the tailgate down on a pickup for better mileage. They tested only one vehicle. I can tell you it works for some, because I have done real-world testing on it and it HAS worked for me on a 1998 Nissan Frontier King Cab.

The same thing applies here. HAI does work for some people, myself included. I have a K&N setup inherited from the previous owner on my CRX, which functions very effectively as an HAI setup. Getting 40-45 MPG highway on an automatic CRX, and making myself land squarely in the top 10 in % over EPA, I can tell you it surely works for me.

[Jay2TheRescue]

@Project 84: I wouldn't try to get your IAT's up any more, since you already suspect that your engine is starting to fail. I'm guessing that you're losing compression? If so, heating the air more, and losing even more power... Well that car may not be able to get out of its own way afterwards. However, after a repair or replacement of the engine I'd totally go for it.

-Jay

[Project84]

I've given up on FE mods.... for now. Been tinkering w/ my Z28 and finally got my Turbo Miata build underway. Right now it's performance. I cannot concentrate on two aspects of the auto industry at the same time and be productive.

Plan is, as soon as I purchase a house (I've been in the market about 7 months now, but I'm picky and want a GREAT DEAL; currently have an offer on a bank owned property in Short Sale, waiting 3 weeks to hear back from them) I'm going to use the garage space to re-ring and hone the Stock block, and drill oil relief holes in each piston, OEM didn't think of that for some reason. Might try some somender grooves for the hell of it while I'm at it, although, I'm not sure lowering the compression any more will help, as the car is slow until about 4500 rpm as is, which it never sees.

If I have to replace more than the rings, I'm going to port the exhaust side of the head and then have it decked, upping compression a bit, carve some somender grooves, evening things out, and hope for a more friendly FE vehicle, that doesn't run on oil, but only uses it for lubrication. lol

2 quarts every fillup (300 miles)

[sc2dave]

with my 96 Saturn sc2, and using Scanguage, i was able to get 42mpg at a throttle position setting of 15% with 17" wheels.I also put a resistor of around 110 ohms to make the engine think it was sucking in 147* air,approximately!

[jeep45238]

Originally Posted by sc2dave

with my 96 Saturn sc2, and using Scanguage, i was able to get 42mpg at a throttle position setting of 15% with 17" wheels.I also put a resistor of around 110 ohms to make the engine think it was sucking in 147* air,approximately!

Which is doing nothing for the vehicle. Your o2 sensor is picking up that the engine is running lean and the computer is dumping in more fuel to compensate for the false reading.

Tricking electronics won't do much at all, but performing the physical changet the trickery is imitating can help.

Right now mine's sucking air approximately 35-45*F higher than ambient (dependant upon ambient and how long I've been driving). It's helped a small amount, but it did help warm the vehicle up quicker in the winter.

[usedgeo]

It has been months since I posted anything. I still like warm air intake on the '01 SL1 Saturn. I now use a liquid air intercooler with a bypass water loop through it. My IAT sensor is screwed into the aluminum so there is a bit of bias toward the high side from heat conduction into the sensor. This gives me quicker warm air and regulates it somewhat. The air temp runs just a few degrees cooler than the water temp. I like it but I suppose it will never pay for the $175 intercooler. I became a bit obsessed.

My original WAI going through the resonator hole was more restrictive than I thought. I gained quite a bit of power with the new set up but could not retain the original air cleaner. I have an oil foam cone air cleaner now.

The engine takes a bit longer to warm up now. The intercooler and heater are enough to cool the engine on cold days. Grill was kept completely blocked most of the winter.

With Somender Singh grooves in the head and balanced injectors my car runs smoothly at 220 WT, 205 IAT and WOT. Never a hint of detonation. Of course your mileage may vary. Saturn's seem to like this. My power is more than I need.

Ernie