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Performance threads All discussions about CoD performnce

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  #1  
Old 02-29-2012, 02:30 PM
Talisman Talisman is offline
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Default Merlins in Russia on 100 Octane fuel

http://www.chevron.com/products/prod...nfuel/toc.shtm

The above link provides the following information. I pressume 100 Octane fuel and extra boost will be available as we move to the Eastern front for the sequel.

FUELCAT History

Henry Broquet's Catalyst - born in Desperate Times
Henry Broquet's fuel catalyst is not just another short-lived magic gadget that claims to work unexplained wonders with car engines. It was developed, tried and proved in the hardest arena possible - the Russian front in 1942.


Rolls-Royce motors meet Lada Fuel!
When Britain sent Hurricane fighters to Russia in 1941, their Merlin XX engines needed the special 100 octane petrol developed for the RAF. Although a supply was shipped there to startwith, the Russians themselves were unable to produce any more. Their fuel was not only lower grade but very variable in quality. Henry Broquet, a British technician, collaborated with them and came up with the tin alloy catalyst, a workable answer that enabled the Merlins to run on lower grade petrol satisfactorily. Why was the grade of fuel so critical? After all, car engines can be detuned to run on cooking petrol by retarding their ignition or fitting thicker head gaskets. You simply could not do that with a thoroughbred Rolls-Royce aero-engine.


Power
The power output of a piston engine depends upon firstly the revolutions per minute (rpm) and secondly the pressure developed in the cylinders. Friction and mechanical stress limit the rpm, but fuel is one of the main factors limiting the attainable power. This is mainly due to the problem of detonation. If the fuel/air mixture is compressed too much, it may not burn evenly but explode suddenly. This gives a very high peak pressure and a sharp blow on the piston instead of a steady push. The energy from the fuel does no useful work but is wasted as heat. Severe or prolonged detonation can blow holes in pistons, burn out exhaust valves and even knock off cylinder heads. Car drivers can hear the characteristic pinking sound caused by the shock waves hitting the cylinder walls.


Octane Rating
Petrol's resistance to detonation is given by its Octane Rating. This is the percentage of iso-octane (full chemical name 2,2,4 trimethyl pentane)contained in a mixture of iso-octane with normal heptane that reproduces the same knock characteristics as the petrol when tested under standard conditions. One of the ways to increase octane rating is to dope the fuel with tetra-ethyl lead. What this does is to steady the rate of combustion and inhibit the sudden temperature rise ahead of the flame front that triggers the explosive ignition. A drawback is that lead deposits tend to build upon the spark plugs so ethylene dibromide is often added, to combine with the lead and take some of it out in the exhaust.


Pre-ignition and Plug Fouling
Another problem with mediocre fuel is that it may have poorly combustible components that have not been refined out, and they leave unburned deposits on the cylinder head and valves. These impair cooling and may get so hot that they act like diesel glow-plugs, igniting the mixture before the spark plugs fire, too early before top dead centre. The effect of this pre-ignition is similar to detonation and equally damaging to the engine. Characteristically a hot engine will "run-on" after the ignition is cut, as though it was a diesel. (Inefficient pre-war side-valve engines used to need decarbonising every ten thousand miles or so because they built up these unburned deposits.)

Lead is Dead, Long Live Tin!
Big European and American oil companies saw no need to take up this development. They had invested a lot in tetra-ethyl lead and had no incentive to try something completely different. But lead is to be banned from petrol by the year 2000. Millions of motorists and boat owners with engines designed for 4-Star are going to have problems. True, they can buy expensive "super unleaded" instead, which is supposed to equal 4-Star. However, this has all sorts of other detonation suppressing additives instead of the lead. Some of these additives themselves are not very nice. Furthermore, they still leave the problem that some designs also rely on the lead to protect valve seats from erosion and stop valves from sticking.
Henry Broquet's well-proven tin catalyst is a better answer than tetra-ethyl lead anyway, improving the fuel before it goes into the engine so that combustion is more efficient. This reduces deposits on the cylinder head and valves, and also the amount of waste heat going into the exhaust. As a result exhaust valves and their seats are cooler and do not need a protective coating of lead. Finally, more efficient combustion means less exhaust emissions.
If anyone needs proof that it works, they need look no farther than those hard-pressed Merlins in Russia!
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  #2  
Old 02-29-2012, 02:37 PM
Talisman Talisman is offline
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Correct link to my post above:

http://www.carburetters.co.uk/Fuelcat.php
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  #3  
Old 02-29-2012, 02:44 PM
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bw_wolverine bw_wolverine is offline
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Interesting stuff. Is anyone still actually denying the use of 100octane?

In this audio documentary, one of the BoB pilots recounts his friend being shot down over the channel and being picked up by a tanker carrying 100octane fuel for the fighters (and how terrified he was at having to be on that highly explosive ship!).

http://www.audible.com/pd?asin=B0032N4YK4
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Using ReconNZ's Pilot Log Book
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  #5  
Old 03-04-2012, 09:21 AM
Skoshi Tiger Skoshi Tiger is offline
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I think there is some dispute about its authenticity. Though it could be a petrol company conspiracy.

http://fuelcatisascam.selfip.com/fuelcat.html
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Old 03-04-2012, 12:24 PM
TomcatViP TomcatViP is offline
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And can 100octane cure diseases ?
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  #7  
Old 03-04-2012, 12:52 PM
Skoshi Tiger Skoshi Tiger is offline
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Quote:
Originally Posted by TomcatViP View Post
And can 100octane cure diseases ?
Not sure, but I've got some good snake oil I can sell you!
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Old 03-05-2012, 08:19 AM
5./JG27.Farber 5./JG27.Farber is offline
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Dont want to get my head bitten off but what are you guys actually asking for?

If they pretty much always had 100 octane sureley if the aircraft can reach the speeds in the book, its running on 100 octane anyway? Yes the flight models are not tweeked yet but I dont actually see what you asking for.

Please forgive my blue ignorance...
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  #9  
Old 03-05-2012, 08:54 AM
NZtyphoon NZtyphoon is offline
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Quote:
Originally Posted by bw_wolverine View Post
Interesting stuff. Is anyone still actually denying the use of 100octane?
Yup
http://forum.1cpublishing.eu/showthr...=20110&page=50
http://forum.1cpublishing.eu/showthr...=20110&page=51
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  #10  
Old 03-05-2012, 01:18 PM
TomcatViP TomcatViP is offline
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Don't know if we have dedicated Mods with such a bckgrd but just in case NZTy there is the ultimate link.

http://www.liveperson.com/experts/he...ne/psychiatry/

You are getting me scared especially considering that all that stuff comes out of your psychotic fear of spawning in any blue fighters when it comes to get the best ride of the era in a game.

Before you insult me again with your dirty accusations of "revisionism" , look at my stats that will show you that I hve no particular interest for any side as I am flying as often strait and slow Hurries as blue E3.

Frankly you'd better step out of this style of "comments" with me

Last edited by TomcatViP; 03-05-2012 at 01:21 PM.
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