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boomerang opeler
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arh mr singh yes weve had him on here a few times now , its very good reading and makes good sense , dont know if anyones tried it but it does make sense

keith performance or general im not sure ?
 

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baz said:
keith performance or general im not sure ?
Or Humour? I'll move this to the General Discussions Forum for now (where I think the related threads are)
 

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Rally Bob did something similar with his dimples in the combustion chamber. He has pictures posted....somewhere....:)
Boy, is this place getting "Big"

Jc
 

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What they're talking about is keeping the atomized fuel droplets moving during compression so that they don't come out of suspension with the air and form puddles. Perfectly atomized fuel is when all the tiny droplets are the same size and remain so during compression. Big droplets take longer to burn than the little ones, so they don't give off their heat in time to make good power.
I think I explained this as simply as possible without going way way into it. Ignition timing gets involved next, the timing is set to prevent detonation when the smallest droplets explode instantly before the bigger ones have burned.
Fuel injection has improved all this because it can atomize the fuel into smaller droplets.
At least thats my understanding. I've been studying this recently to figure out how to use higher octane with lower compression ratio. And the various fuels that are available. Oxygenated racing fuel is interesting. So is nitro/methane!!
Bob Dimples are on the same track as the grooves. They go where burn patterns and colors indicate fuel has been puddling.
I'm a believer in it, but wouldn't expect to gain any significant fuel economy with it. Maybe a hundreth of a second lap time, yes.
 

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FLAME travel pure and simple and oh yes timing has a big effect
Fuel drop out another biggie ect ect
Question how much pressure is in the combustion camber when you put the pedal to the metal....
 

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Good question, and I have no answer. This thread is gonna turn into a mind boggling, heavy discussion, I hope. I have been trying to get answers to questions for some time in numerous forums here and there but the answer is steeped in mystery...
Other variables are intake valve closure timing which can alter compression ratio, it is a dark science involving intake tract reversion and more.
See why I'm into the adjustable cam sprocket? Playing with valve timing is huge. And to do it right you need a few camshafts to experiment with, every grind is different.
Understanding all this is the key to moving from "glad to finish the season fifth in points" to "First place season points", leather jacket and all.
You know what I do with my Internet time...
 

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the internal combustion engine as we know it ..is very inefficient to say the least 90 % of the power is going out the tail pipe as heat
Variables dang there a s**t load of them good luck
 

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Opel Key Master
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Grooves in Combustion Chamber

I actually caught a show segment about this guys theory and I believe he has patened it, but how do you prevent someone else from die grinding grooves into their head's cumbustion chamber. It was interesting, but I think other things could be done also to enhance cumbustion. They say the squish area combustion chamber can be ideal if everything is set up correctly, but unfortunetly so many factors affect that like head gasket thickness, spark plug angle, piston shape. I wouldn't go cutting grooves into a head thinking it is going to mix gas better air, but do more work maybe on creating turbulance for mixture in the intake-study many options before doing an evaluate if any result would be found
Keith
 

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wrench459 said:
the internal combustion engine as we know it ..is very inefficient to say the least 90 % of the power is going out the tail pipe as heat
Engines are about 25% efficient. Just read it an hour or so ago on the net so you know it is gospel. :banana: I do believe that 25% is fairly accurate.

Harold
 

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Harold, that is one really long article, but its got a lot of info in it. It's interesting to note they recommend polishing the entire combustion chamber, to include the valve faces and piston tops, something I did on my racing bike engines way back in the 60s, I even polished the exposed valve stems down to the seating area. My reasoning for that was to reflect the heat and increase flame propagation. I got that idea from watching an old Mickey Rooney movie on Thomas Edison. The scene was where his mother was ill and needed an operation, but the doctor claimed he couldn't do it because of insufficient light. Mickey, AKA Thomas Edison as a youngster placed numerous kerosene lanterns between mirrors and the reflected light was more than enuff for the doctor to do the operation and save Thomas' mother. So, based on that idea, that worked BTW, I mirror polished all my engine combustion chambers. I don't really know if it was sucessful, but with some gearing changes I was able to change my top speed from 55 MPH to 70 MPH on my old Honda 90 CC bike. Of course there were other things added to the engine as well, like a cam, intake/carb/port matching, mirror polishing of the exhaust and intake ports, normal stuff for back then. The general consensus was the engine was turning close to 11,000 RPM with a 13-70 final drive. To think I was on to something way back then is unreal. But then again, I had adjustable pneudraulic front forks on my bikes back then too when everyone else had springs in theirs. :yup:
 

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Squish, Squirt & Quench

I note that the grooves cut by Mr. Singh are 'aimed' at the spark plug - looks like as the piston moves over TDC the groove directs the mixture out of the quench area directly towards the spark plug as a high-speed jet.

There is certainly some good sense in the Summit Racing engine building article too. I am sold on Keith Black/Silvolite hyper-eutectic pistons but the crown polishing and possible ceramic coating raise this area to a new level.

In the early days I tried 'ceramic coating' by spraying the heads of pistons with VHT Header Paint. Worked well - except the damned stuff flaked off after a while and the tiny flakes got pounded into the valve seats! The white stuff worked best and the pistons had to be 'cooked' on a domestic oven at around 300 degrees F to pre-cure the paint.

BTW: Don't get caught 'cooking' pistons or exhaust manifolds in a domestic oven - it will cost you a brand new Thermo-wave oven!!! Which is even BETTER to bake manifolds and pistons in ........... :D
 

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Fuel atomization

jeff denton said:
What they're talking about is keeping the atomized fuel droplets moving during compression so that they don't come out of suspension with the air and form puddles. Perfectly atomized fuel is when all the tiny droplets are the same size and remain so during compression. Big droplets take longer to burn than the little ones, so they don't give off their heat in time to make good power.
I think I explained this as simply as possible without going way way into it. Ignition timing gets involved next, the timing is set to prevent detonation when the smallest droplets explode instantly before the bigger ones have burned.
Fuel injection has improved all this because it can atomize the fuel into smaller droplets.
At least thats my understanding. I've been studying this recently to figure out how to use higher octane with lower compression ratio. And the various fuels that are available. Oxygenated racing fuel is interesting. So is nitro/methane!!
Bob Dimples are on the same track as the grooves. They go where burn patterns and colors indicate fuel has been puddling.
I'm a believer in it, but wouldn't expect to gain any significant fuel economy with it. Maybe a hundreth of a second lap time, yes.
Have you tried adding ~1 ounce of acetone per 4 gallons of gas? According to prevailing theory, acetone acts as an 'enabler' to do exactly that, atomize gasoline into finer, more uniform droplets. This produces a more even burn, somewhat more power and results in a bit better gas mileage, to boot.

Have personally tried it for several months now in my Kadett with everything stock and using the same brand 87 octane gas. I've improved my mileage by a little over 1 mpg and the engine runs a little smoother, or at least it feels like it. Might just be something to this . . .
 

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Acetone

That stuff is a bit hard to find but I finally found some at a paint store where it is sold as a degreaser. $14 a gallon though! Well ... for 4 litres anyway. :)
 

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tekenaar said:
Have you tried adding ~1 ounce of acetone per 4 gallons of gas? According to prevailing theory, acetone acts as an 'enabler' to do exactly that, atomize gasoline into finer, more uniform droplets. This produces a more even burn, somewhat more power and results in a bit better gas mileage, to boot.

Have personally tried it for several months now in my Kadett with everything stock and using the same brand 87 octane gas. I've improved my mileage by a little over 1 mpg and the engine runs a little smoother, or at least it feels like it. Might just be something to this . . .
Otto, if you use gas with a higher octane level wouldn't you also get a better mileage?
 

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boomerang opeler
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i have used acetone since if was mentioned on here last year and i was getting 4 mpg more on my ford wagon

we get 95 or 97 ron so it might do better the higher the octane but i think its down to injection and not a carb

i have a friend using it in his diesel van and he says its much smoother and doing better milage too

for those who have not read it look here
http://www.opelgt.com/forums/general-discussions/6873-acetone-fuel.html?highlight=acetone
 

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GTJIM said:
That stuff is a bit hard to find but I finally found some at a paint store where it is sold as a degreaser. $14 a gallon though! Well ... for 4 litres anyway. :)
If you want to try it in smaller amounts, some fingernail polish removers use acetone. I don't know how pure it is though. I have two teenage daughters so don't even go there. :D

Harold
 

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2 Fast 4 U said:
Otto, if you use gas with a higher octane level wouldn't you also get a better mileage?
With acetone I don't know. The higher the octane rating the more resistant to burning it is. You gain little if anything but a thinner wallet from using a higher octane than is needed for your engine. In some cases mpg is lower. I seem to recall that there are less BTU's in high octane fuel also.

Harold
 
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