Hydrogen Peroxide Injection Systems for Engines

It's about improving efficiency not melting your (valves) engine in the process

old muscle cars are overdesigned so using Nitro should not have much long lasting effects but on recent high tech car engines nitrousoxide is not so forgiving IMO

There seems to be somewhat of a small difference between nitrous oxide and and the current thread, "Hydrogen Peroxide". Nitrous Oxide has been used as a horse power maker for a long time, when added to a little gasoline. Hydrogen Peroxide doesn't need any help. However as for this thread. I highly recommend that all percentages of the H.P. be left in the container. Automotive engines were never designed to accommodate the stuff. If you need to clean up the innerds of your little petrol burner, use the stuff that has been engineered for that purpose. You know, stuff lile carb. cleaner, fuel injector cleaner "Bardal", and even Berma Shave.

TMF

Cleaning up the innards of an engine was never the intent of the original question nor of the focus of the thread discussion.

what major changes would have to be made to engine design if h2o2 or NOx have to be used safely.ignorin containment and delivery system for respective stuff.we can talk about delivery if essential.

According to the PFI systems dealer no modification is needed. He has a couple of installs that have ben running for about a year.

Sorry Elnay, the original post said cleaning up the emissions of two stroke engines.

Blue

I found this link while trying to find out what happened to PFI. I was communicating with one of the 2 Swedish brothers that had it pretty well perfected in the late 90's, and they had some unwanted interest in their accomplishments from the oil industry, then I lost contact.

There are some misconceptions in this thread.

On a 2 liter car (Saab) 1 liter of 50% H2O2 lasted 10,000km. So the consumption was so low engine corrosion is a mute point. For safety, it was stored in a bullet proof aluminum container. It allowed for a more complete burn during the work phase of the engine cycle. (Even if 99% of fuel is burned in normal engines, only what pushes the piston down counts). PFI allowed for a leaner mix - between 20-30% leaner and this led to better fuel economy though not huge... and no doubt depended on driving style.

The most dramatic gain was in torque. Too much H2O2 at the top end of the rpm on a stock engine simply broke the crank. So they dialed it in for modest gains, and mostly in the lower rpms where the crank seemed to be happy. The torque gains in the lower rpm band (read a flat torque curve not a huge increase in peak torque) meant that once rolling you could shift the Saab into 5th and never need to shift again.

They commented that the fuel burned not just completely but so quickly I suspect ignition advance was dramatically reduced while PFI was injected.

Emissions were cleaner also due to faster more complete burn.... achieving the results of a good cat without the wasted fuel.

The very strong concentrated H2O2 was passed over a catalyst and mixed with air before injecting into the intake as I recall. So was injected as a very fine atomized mist. In engines that were tuned to run the system for power not emissions - it was unbeatable in snow mobile racing at that time.

Is PFI commerical? Well the good results were with 50% pure not 3% gargle juice, and in a post 911 world, it is unlikely politicians are going to encourage Joe Average to buy containers of it.. but allegedly, it worked just fine when done right!

Maybe the 2 brothers blew each other up later? I still think PFI is of interest if done professionally.

Onto modern ICE engine fuel economy. Good point about why no massive gains over the last 30 years. You can get better mileage on most bigger gasoline engines by remapping the ecu. They are set to run rich and keep the cats hot, factory tunes waste a huge amount of fuel. They also have to accommodate the idiot that will try towing a heavy boat up a hill in a gear too high and floor it.

I average 25mpg imperial (21mpg US gal) city/highway mix in my large 4 door family saloon with 4sp auto and remapped LS1 engine. It makes 240kw (320rwhp) at wheels and gets 32mpg (27.5US mpg) at cruise. The gains were from exhaust and air improvements (small gains) and a remap (that's the biggie). The remap added 40rwkw and about 100km extra per tank of gas. In other words - a better tune is all it takes on some of these pigs. Cruise economy is a still safe 15 odd:1 on 93 octane and power mix is around 13:1. Our climate is mild so there is no engine heat issues at all - runs better than ever and clean.

If you want to spend more - we got 30mpg (US Gal so 35mpg imperial) out of a 8+ liter Viper V10 that was twin turbocharged. Same engine made 950rwhp (about 1100 at crank) on full boost. Nothing really trick here, certainly nothing fringe (though I'm all for new ideas). Keys were very good piston design to match chamber, tight squish, and accurate control of low impedance injectors... stock gearing, good tune, drive on vacuum at highway cruise. Obviously the car does not average 30mpg, but it does average far better than most would think... mainly because it spends most of its time on high vacuum as it is too dam fast to keep any throttle in it for long on a public road, not even the best superbikes have a chance from a 120kph up roll on.

The irony is you can get far more accurate control over big aftermarket low impedance injectors than you can out of stock (or aftermarket) high impedance ones... which is why you can get full race engines to idle around like a puppy with good EFI, and why you can get decent cruise mpg out of a well built street race engine.

By anyones reckoning, 30mpg out of a 1000+ hp 8 liter engine is very good, tho I doubt we are close to what can be done... but I'll leave it there ...lol