Water on the brain burn

Assuming 150 crank hp sought, as overestimate to give conservative safer
results of following logic process with rounding up each conversion to fudge some more. Any obvious holes in my brain showing up here?

Takes about 0.5 lb fuel/hour per hp = 8 oz/hr/hp or 800 oz for 100 hp hr
150 hp/hr would burn 1200 oz hr. There are 240 cc in 8 oz. Each oz. is 30 cc.
So 2400 cc per 100 hp hr, or 3600 cc gas for 150 hp hr.
A US gallon of gasoline averages about 6.25 lb or 100 oz, so 150 hp needs 150 oz or 1.5 gallon fuel/hr. 1.5 gallon / 60min = 1.75 oz/ min, x 30 cc = 53 cc gas/hp/min. Fudge factor that to 55 cc.

My obsolete engine needs effective compression ratio 17:1 per liter to
produce torque pressure enough to reach 150 hp @ 7000 rpm. So 112-114 octane required to allow full ignition timing without detonation.

To get 116 octane requires 15% water mass of total fuel mass burnt. To
keep making power w/o lowering combustion pressure by too rich fuel,
water should replace/displace fuel. Leaving crude fuel delivery alone,
water injection will automatically substitute fuel leaning at max heat-power.
So 15% water per 55 cc fuel a min = 8.25 cc/ min water spray against 10 PSI intake blast should do it.

Btw expansion of inert atmosphere N gas heating does the loins share of the pressure work, not hydrocarbon oxidation vapors. Steam also add its push too.

So 15% water per 55 cc fuel a min = 8.25 cc/ min water spray into10 PSI intake
blast to do it. 2 liter water bottle, 65 oz, should give 8 min worth of anti-
detonation power while consuming almost a gallon of 91 octane of gasoline.

Water-methanol nozzles come rated @ 100 PSI. Water jug can take
40 PSI. So leaves ~30 PSI to force water into air blast, starting at
5-7 PSI as knock sensor indicates. So 1/3 nozzle pressure means
60 cc nozzle to flow enough up to 20 cc to give a big reserve to regulate
back some if full flow not needed.

So I ordered 60 cc nozzle for $20 in 1/8" NPT brass and SS elbow.
Also ordered, 12 v, 1/4" NPT, normally closed solenoid valve to work nozzle.
Adjustable manifold pressure sensor switch on hand triggers valve and
new ignition curve. Now to hunt for two spiked dog collars to complete
hardware install..

hobot


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1cc water =1700cc steam. How does this factor into your compresson ratio. Are you using H2O as comp boost and octane boost? Too much factoring for my lil brain. With that much sudden increase of compression at high rpm aren't you afraid of blowing the head off the top of your motor? Hydraulic? Is that the right term for what im thinking?

I think it would be best to inject the water in after TDC or it will cool the combustion chamber , delaying ignition, retarding flame propergation, Etc.
If injected in after TDC then the water will remove heat of combustion (BTU's) equal to the heat of vaporization (BTU's) necessary to change the water to water vapor. Then it will expand as the piston goes down keeping the MEP (mean effective pressure ) in the cylinder higher) for more of the stroke.
Like a diesel engine which has a high MEP for a long duration due to the fuel injectior still injecting fuel into the cylinder during the power stroke (depending on load).
60 cc seems like a lot of water!

2000cc lasts 8 mins at 7000rpm, so thats 56000 revs in 8 mins with an injection every rev in alternate cylinders.

So 2000/56000 equals 0.036cc per injection, where does 65cc fit into this scheme?

Unread postby caddy chris » Wed Feb 09, 2011 10:33 pm
1cc water =1700cc steam. How does this factor into your compresson ratio. Are you using H2O as comp boost and octane boost? Too much factoring for my lil brain. With that much sudden increase of compression at high rpm aren't you afraid of blowing the head off the top of your motor? Hydraulic? Is that the right term for what im thinking?

Click to expand...

Oh yes there is steam made even w/o water injection as combustion byproduct.
Thanks for the volume liquid-vapor ratio, I did know prior. Water acts is a number of ways to influence combustion process, evaporation phase change absorbs heat, but so does absorbing IR photons that transmit heat a faster lonrer ways than convection or conduction. Plus water ain't really H2O, its got all kinds of clusters and ionization states that are fast acting catalysts that crack hydrocarbons to slower fuller burn radicals. I'm mostly using water as anti-detonation fluid, but yes it adds steam pressure too depending on amount sprayed. There is a point of too much water but that just bogs power or stalls out. No damage, no hydro lock, just dial back water valve till works.

There should be no sudden CR increase, just smooth following of throttle from dynamic CR 7.5 to full boost-full ram charge- full rpm- steep rise to 17 or more. Boost levels with centrifugal Drouin is totally dependent on how fast one dares load the engine by throttle snap. Slowly go WOT on positive displacement compressor and full boost ratio hits no matter the rpm or load. Drouin is more a fan blower, not compressor so if 'slowly' rolling on WOT it may not make much boost over just cruise but will make as much boost power as needed to break drive train or traction, not the engine. If bike too light or tire grip too weak then impossible to load to max boost like on a dyno. Just spins out or leaps ahead.

Also as rpm/piston speed increases, it can some times just out run detonation pressure spikes to benefit running ragged edge of best torque pressure spikes.

Ugh every fastener is TimeSerted but I'm seriously considering a cable tie down over the head to the cradle/front mount. My top link steady design allows for this, plus spring to compensate for the heavier 920 and Drouin.

Bruce MacGregor said:

I think it would be best to inject the water in after TDC or it will cool the combustion chamber , delaying ignition, retarding flame propergation, Etc. If injected in after TDC then the water will remove heat of combustion (BTU's) equal to the heat of vaporization (BTU's) necessary to change the water to water vapor. Then it will expand as the piston goes down keeping the MEP (mean effective pressure ) in the cylinder higher) for more of the stroke.
Like a diesel engine which has a high MEP for a long duration due to the fuel injectior still injecting fuel into the cylinder during the power stroke (depending on load). 60 cc seems like a lot of water!

Click to expand...

Hehe, snowmobiles and jet ski's 2 strokes inject water in exhaust to change the tone of the tune and sonic back pressure waves. If one sprays in enough water there is still enough left over after TDC to work as you suggest. This is another against the grain features of Ms Peel to surprise everyone, Most water kits brag about how fine a mist they produce, but that shoots some of water advantage in the foot, missing out on the great amount of phase change energy small droplets offer on way to the chamber and inside and durring the burn and exhaust release. Just turn water meter up/dn till sounds and pulls best.

If the water entered ahead of the impeller the evaporation cooling makes charge denser so ups the Drouin efficiency. But the soft impeller nearing 50K rpm might be eroded over time. That can be reduced by water spray aim at center of impeller to lessen blade impact cavitation. If I seek more boost stupid power, Peel has another 'secret weapon' - spray methanol ahead of impeller, as it would flash evaporate/cool charge w/o impact and spike Drouin efficiency over what water could and adds to feul enriching if needed or sought.
To really blow minds, I could then put industrial strength hydrogen peroxide in the water sprayer to oxidize all excess fuel and maybe some rocket action out megaphone : ) There is also a compromise option, use windshield washer solution in 40=50% methanol. This is very common turbo engine way to go.
So I can use drinking water to gas station window fluid to keep detonation at bay about anywhere I go. Might even make more power on cheap 87 octane as that is what sold me on the PowerArc ignition, it solved hi octane ping/knock on over done Harlyes and made best power on cheapest most explosive gas.

The nozzle I'm getting is made to atomize by 100 PSI or more feed water. But with 30-40 PSI against 10-12 PSI boost if won't break up as fine, hopefully absorbing intake heat prior to head but still fluid drops to further stuck up chamber heat fo compression, then some left over to tame the flame burn and maybe enough letf over to power stroke and exhaust pressure exit.

I don't have skill, space or spending for a set up to spray against chamber pressure with valves closed. Well designed + accidental simple set up should just do it, I think.

kommando said:

2000cc lasts 8 mins at 7000rpm, so thats 56000 revs in 8 mins with an injection every rev in alternate cylinders.

So 2000/56000 equals 0.036cc per injection, where does 65cc fit into this scheme?

Click to expand...

Oh good hoped to get a confusing response to figure out and set me straight.
I could not keep my mind straight w/o typing out each step and going back froth till seemed right at the time. Decimal jumps in fractional ratio can stump me too.

First off, I don't think I or Peel can stand 7000 rpm in real life, just once or twice for a sprint or speed or dyno attempt. Can't imagine ever being able to use nearly full power for more than hand full of seconds a go in real life or even on more technical race tracks. I hope with the special ignition and the too radical drag cam - dynamic CR will stay below detonation zone while delivering normal 920 power response. If I feel a bit perky and want to smoke tire before leaning, giving a burst more than a sec is way too long anyway. If water works out and engine not a powerful as expected, so need water more often, not too hard to add bigger or extra water tank.


My figures are for total fuel burn of both jugs, so a bit over estimated max fuel flow as 55 cc per minute. 15% of that is 8.25 cc a min split by manifold to each chamber's 4.12 cc's worth. Off the shelf nozzles are not made for one liter engines and assume hi pressure pump fed. So the read made nozzles smallest feed 60 cc/min. But if I lower fe water to 30ish PSI and put a meter valve in the way I think I can get mutli droplet size spray in ball park amounts then does get blasted to smitherines by placing at out let of the impeller housing. If this don't work then I can make my own nozzle by drill hole so it hits a place to splatter into air blast, just as long as can force water enough against the boost. I came up with air pressure to push water, before I realized I could not fit the crank end charger. Now have power enough for good pump but air has other uses on Peel so sticking to Plan A for now.

Extra electric power may be neeeded to pump oil cooling jets at pistons, but I'm now told there is a lot of oil bypassing going on at hi rpm, so maybe just tap that when excess pressure rpm flow reached, which is when extra cooling needed, but not otherwise, I hope.

May have to spritz water w/o the Drouin belt on, when lugging up slopes with cargo or playing in ravines with MX bikes. Ain't figured out the pressure sensor logic for that yet. Vacuum drop per rpm must be the trigger not boost rise.

The Drouin will run fine with out the belt, once the engine is running. It turns into a giant fuel mix master running on engine vacuum.

Can't comment on all the math, just my experience to offer.

I have a 150 psi water injection pump that delivers a 50/50 mix of H20 and Methanol to my 2.2 Shelby GLHS; the mixture's delivery is controlled by a pressure switch reading off the intake manifold and it is set to open the injection system's solenoid valve and deliver the mixture at 15 pounds of boost. Boost peaks at 25 pounds. That means it is "fat" in the 15 to 18 pound range but just right near and at peak boost.

The car runs with the alky injection on California's crummy 91 octane. When I can get 110 unleaded at the track, I can turn off the injection and run 25 pounds of boost without the alky injection. So, that's what the alky does for me - I can run 91.

A single nozzle is located after the blower, after the intercooler, but ahead of the throttle plate.

As for idea of injecting ahead of the blower, I wouldn't - tears up the blades.

Wonderful report to me Xback-, Implies I'm in ball park of pressure and octane survival on 91 oct base fuel. I really don't want to use methanol mix d/'t need to find a refill away from home or need to carry extra to top up. But its a fudge factor I'm keeping in mind.

Peel has a number of other anti-detonation features, by clashing rpm vs torque set ups against each other. I think Peel will be able to run on just 91 octane in normal zone of Commando performance w/o throttle use enough to induce boost, which again is strickly a matter of how fast throttle opened, not how much throttle opened. Cruise will definitely not need water but a quick pass will for a few seconds. Drouin is a bit under size for 920 but advertised effective up to 1,100 cc
and 11 CR. So I've upped CR to 10.5 instead of lowering it as other boost users do for more max boost power. Mild boost allows simple draw through induction rather than pressure sealed and balanced blow through carb or fuel injection.

The two biggest mistakes with boost are too much ignition and too much compression; they are largely functions of the same thing. Many have tried to run higher compression with boost and their hard and expensive experience taught them otherwise. I wouldn't go more than 9:1 and I would be looking for an electronic ignition/injection that pulls timing upon detection of detonation. Now we're talking O2, knock, and EGT sensors too.

Short of that, keep the compression low, the ignition stock, the fuel rich, and the boost at 4 or 5 pounds.

Go slow, once you get it running well, don't get greedy, incremental changes.

Hehe, talk about being tested on combustion physics, Ms Peel flys directly in the face of most the World's tested power making wisdom and paths. Peel may end up the most powerful road going Cdo fielded but that's because I'm not following the ways maximum to make power and for sure not by hi rpm. Even going against Drouins own advice not to use with an aggressive cam as a 2S. Pure drag race only cam for Peel is my seeming illogical path to follow my ' There's Exceptions to Every Rule w/o Exception' motto. Still even if I had 200 hp on tap it would pale to the benefits of the INSANE Grip and Load handling the Rump Rod and its two helpers provide. Rod Links Matter MOST to me.

Peel must work good w/o the blower belt on, so with such extreme cam - need some good CR to even start and idle and tolerate 91 octane w/o water all the time.

Anywho if ya care to creep up to speed on this issue, here's a starting place that really don't apply exactly to Peel because positive "compressors" don't work like Drouin non displacement "blower" boost curves for power or detonation.
What ya might glean from this is putting same size blower on bigger engines lowers the boost potential, unless the CR is bumped up enough. The other thing to keep in mind is what happened to those detuning Combats by merely putting in milder cam, bad ju ju knocking pinging - i hope to dodge.

http://www.musclemustangfastfords.com/t ... index.html

Yep, a higher CR makes more power but fuel is the limiting factor.

Quoting from the linked article -
"Remember, this 5.4L 4V . . . . . running a steady diet of C16 (high-octane) race fuel. Attempting to combine a high static compression ratio and elevated boost levels is a dangerous affair on pump gas. . . . ."

I agree, more compression, more advance - great - the more the better, but dependent upon fuel.

Already been figured out before my time by Ricardo to use water instead of fuel octane. Also in production by Mercedes hi CR Kompressor models. Ricardo showed how to get beyond hydrocarbon fuel octane and enrichment limits. Mercedes and others know how nice it is to take a good hot rod engine and add some boost to get the pull earlier and keepl going up even stronger till red line. Its tricky to do on an obsolete engine, so all the more pleasing if I can pull it off. I've left some good fudge factors in set up to decompress if needed. But do expect I can just snap throttle off idle and sit in place smoking or kick rear out instantly no matter the grip to get better aim on thrush through a turn. Also want it to take fair throttle w/o spin up on slick slopes carrying a load. Can't forget Ms Peel must always keep THE Gravel travel in mind. Thank goodness everything that helped that helped tarmac as much or more.