14 replies to this topic

[SJ Lambert]

Boo hiss. Avgas is gonna depart circuit racing

 

Even worse, sooner or later it will no longer be formulated for aircraft.  Dang and blast......

[Ray Bell]

You're just in time for all the good things, James...

Elfin Monos and 300s are Historic and Historic Racing is the best racing going.

[chunder27]

Goood job there are no 2 strokes racing much anymore in bikes, it was all rage in the 80's! Or am I meaning blue gas?

Edited by chunder27, 09 November 2017 - 14:10.

[Sebastian Tombs]

Quite apart from the inability to use Avgas130 in racing cars the lack of its availability will have a disastrous effect on the ability of classic military and other aircraft to fly.  It is not the Octane number, which is a measure of the anti-knock capability and hence fuel/air ratios and compression, but the use of Tetra Ethyl Lead (TEL).  All high-performance aircraft fuels since the 30s have contained TEL up to 3ml/gal and some even 4ml/gal.  A Merlin, for example, could be modified to run on lead-free...the operative word being "run" but it would be currently impossible to gain a CoA for such a modified aircraft even if it could perform safely.  100VLL (Very Low Lead) has been developed as has UL102, an unleaded aviation fuel developed by the US company Swift Petroleum.  However, as yet NO aircraft certified to use 100LL has been certified to use unleaded.  This situation has been going on for 25 years and still no effective lead-free replacement for 100LL in all aircraft has been found.  Luckily there is a very strong lobby in the US but the environmentalists also hold a lot of cards.  High-performance 'vintage' military aircraft fly in miniscule numbers around the world but...if you want to continue to see, for example, the Battle of Britain Flight then all enthusiasts must take every opportunity to make their voices heard.  There's a lot about this on the web, Google is your friend 

 

ST 

[BRG]

Classic aircraft aside, general aviation is stil heavily dependent on piston engines, which need Avgas.  So a solution will need to be found and doubtless will be.  The only reason it hasn't so far is the incredible conservatism of the aviation business.  They are still using magnetos - even NASCAR doesn't do that!  Although it is conservative for good reasons; better to use tried and tested technology than come to grief using some cutting edge stuff that turns out not to work just when you need it.  Anyway, once they sort the issue out, it will doubtless trickle through to motorsport.

[SJ Lambert]

http://www.shell.com...2-30071515.html

 

   

[SJ Lambert]

https://www.nbaa.org...ittee-avgas.php

 

It looks like there had been 20 years of unsuccessful endeavour to develop a lead free replacement Stateside back in 2011.

 

My American commercial  pilot mates still reckon it's going the way of the dodo though........

[SJ Lambert]

https://www.bp.com/e...s-produced.html

[Lee Nicolle]

This is a sore point. Unleades fuel is only suitable for engines designed for unleaded fuels. We have a situation on our roads now where we still have thousands of older cars running on unleaded causing far more enviromental concerns that TEL. Unleaded is carcliogenic,  and the lower octane in most is causing both engine damage and poor performance as the timing advance is knocked back so detonation does not occur. Causing in some cases overheating and even more raw fuel being pumped out the tailpipe.

 

As for motorsport all of the above apply. I suspect even Production Cars are probably  tuned to make the engines 'dirtier'.

 

HQ Holden Racing has been on unleaded now for some years and all had to rebuild engines for the mandatory lower compression allowed in the rules and the distinct lesser power achieved, something like 2 sec a lap slower around Mallala. But ofcourse these engines are decidedly dirty as the Holden chamber is not very good to burn unleaded so a LOT of raw fuel is exiting the cars. A Catalytic converter would help some but not much as the exhaust temps are probably not as high.  IF they were allowed to use a Multi Spark ignition is would help and also give some more power as well. It has been tried on the dyno and emmissions were a bit less and more power was found. But nowhere near the 11-1 plus Avgas engines levels. Where emmisions were if anything less!

 

V8 Stupidcars have tidied up their act a bit, far less flame belching on overrun but again will never be clean engines. Even with the ethanol blend fuel used. which also requirers a lot of ignition. Reutedly cleaner emmisions however. But that is reputedly!

 

Sprintcars and most speedway classes use methanol.Which is carcligenic. Like many I get a hangover from the dust and methanol at speedways. I do try to sit downwind but you still get both. A couple os speedway tyes I know of have cancer supposedly at least in part caused through methanol.

 

There is some modern aftermarket cylinder heads around that make good power on unleaded, they are designed for it. They still require very good ignition though ofcourse. And are not enviromentally nice.

 

CAMS really is being dumb. And what is new? AVGAS will still be made as otherwise Aeroplanes will fall out of the sky. There is various unleaded fuels to replace leaded Avgas but is not legal to be used in most planes.

Interestingly  pilot friend told me that a jet engine can use unleaded fuel for short periods as an alternative to jet fuel. Emmisions? Who knows!

 

A friend went to Eastern Creek recently where they sell the unleaded AVGAS and he noticed the power was not the same, and even then he was on a mix of AVGAS and the substitute. This on an Nc Torana.

GMH retired the  venerable Holden 6 as even with the efi system it was too hard to make legal for unleaded fuel. Then with exchange rates burnt themselves badly on every Commodore VL with the RB30 Nissan engine!

 

All the Greenies should be made to sit in a basement car park for a week! They may change their minds as rich cold start mixtures can be eye wateringly horrid. Let alone the emissions.

 

Has CAMS came up with an real alternative?  I have two race engines here and one to be built that are all Avgas engines. All around 11-1 compression. On all a bit more would be nice but all are simply flat top piston engines. And a Holden 6 really is no better over 11-1 anyway.

But none will run on 98, Not even the Agip stuff which is about $6 a litre. Avgas is bad enough at about $3.70.

 

And the biggest problem with 98 ULP is that it is so inconsistent. On my Ford Galaxie cruiser it cost me a set of pistons as some bad fuel detonated it too death. Twice! That with 9.8-1 comp. The replacement pistons  were 25 thou further down the bore as all the piston manufacturers have decompressed the pistons. BUT the volumes made under 8-1, with the original heads with a 50 thou cut and the original comp was 9.1-1. Which at that it would have been such a gutless thirsty dirty slug!  I had to use heads with the far smaller chambers [302] and am back to 9-1 and it is not near as sharp as it was with near 10-1. Meaning to do the same job you use more throttle.

And yes it does have a modern Holley, a better manifold and more importantly multispark ignition. It likes the Liberty 100 octane ethanol blend, and pings bad on 95! And that with a conservative ignition curve and total. All the 'mods' to the engine make it more driveable. It is almost like a efi engine when cold. but take away the more modern carb and the ignition it would be a pig when cold.

Though even with Flashlube [manganese] I shudder to what it is doing to the engine long term.

 

Modern engines, and I mean this century, are designed for poor fuel and go ok. And stay clean inside with far less carbon build ups.

 

BUT and a very big but is that unleaded seems to be hydroscopic and if the car is left for extended periods the efi pumps die and sometimes the tanks rust as well. And the stuff has a thirty day shelf life. After a few months some vehicles struggle to start as it has gone off. And often was poor to start with.

 

Avgas has a far longer shelf life. And being Avgas is far more consistent in quality. See my above comments.

All of which for a racing engine is very bad news. And currently 98 is usually over 20c a litre more at the pump as well. Modern efi computerised engines mask the worst of bad fuel but not a carby classic race engine.  I suspect there will be a LOT of engine failures next year.

[Lee Nicolle]

Classic aircraft aside, general aviation is stil heavily dependent on piston engines, which need Avgas.  So a solution will need to be found and doubtless will be.  The only reason it hasn't so far is the incredible conservatism of the aviation business.  They are still using magnetos - even NASCAR doesn't do that!  Although it is conservative for good reasons; better to use tried and tested technology than come to grief using some cutting edge stuff that turns out not to work just when you need it.  Anyway, once they sort the issue out, it will doubtless trickle through to motorsport.

While my knowledge of aircraft engines is poor I do know that modern, read this century aircraft engines is that most now are efi and modern ignitions. BUT the engines still require 'better' fuels as if nothing else height effects mixtures and air density. Electronics help ofcourse but still can be a bit suspect.I believe that Avgas allows more ceiling height.

Magnetos are still used in some older engines that are in regular use though, but older planes and possibly Eastern European models.

[Bob Riebe]

VP fuels now provides the fuel for the Reno racers, do not know if anyone else still makes the high performance stuff.

Phillips 66 Flite Fuel is long gone. Does Aeroshell still exist.

There may be others who make aviation fuel but VP is the only one I know of.

 

The local aircraft mechanic here told me Low Lead aviation gasoline makes the highest test car fuel low lead in comparison.

 

[Lee Nicolle]

There is in the US Rockett Brand racing fuels. Which it seems range from unleaded through to serious leaded. Google their website. It is used by the Hot Rod DragWeek competitors though which version I do not know.

 

Also many get confused with Racing fuel and Avgas, Here in Oz at least it is the same product. Avgas is certified and when bought in drums they are new drums, proper petrol drums too unlike methanol drums which are the light duty oil drums.

In the past I used to buy Avgas 100 cheaper from Shell than RF100.

[10kDA]

While my knowledge of aircraft engines is poor I do know that modern, read this century aircraft engines is that most now are efi and modern ignitions. BUT the engines still require 'better' fuels as if nothing else height effects mixtures and air density. Electronics help ofcourse but still can be a bit suspect.I believe that Avgas allows more ceiling height.

Magnetos are still used in some older engines that are in regular use though, but older planes and possibly Eastern European models.

Most newly-developed engines hitting the experimental market now are electronic ignitions and some are fuel injected but the vast majority of aircraft piston engines in service and in production are carbureted, magneto-ignition older designs. Rotax has made some headway into the European lightplane market but they have nothing to compete with the 150-160-180hp Lycoming engines. Many airplanes that would work well with the Rotax 912-914 are equipped instead with the relatively ancient Continental O-200. It has become painfully obvious to many in the aviation field that complexity and additional systems supply additional failure modes. There is nothing wrong with magneto ignition in airplanes. No charging system nor battery is required. Mags have a hard time generating adequate spark in high compression cylinders; airplane engines are low-compression designs. If the engine quits due to running a fuel tank dry or mishandling of the tank selector, the engine does not resist the windmilling prop and you can close the throttle, switch fuel tanks, and the engine will likely restart right away, maybe with a little help from the engine-driven fuel pump or a boost pump if you are flying a low-wing. Ask me or any of the countless others how we know. High compression engines require a starter. If your efi system's high pressure pump (which is not even present in a carbed gravity-feed fuel system) runs dry, can you re-prime it in flight? Can you navigate a multi-step restart checklist while looking for a safe landing spot if you can't get it restarted? It's not like you can coast into the pits at a NASCAR event or to the side of the road and call AAA. I have raced, and I fly. The requirements for each are vastly different. 

[SJ Lambert]

Doing away with Avgas is un-Australian. Asking Jack Brabham back in the day or to now force the running of say, a period F1, a Tasman or even an Anf1.5 car on anything else would be tantamount to forcing our Don Bradman to use a bat made out of plasticine ......    

 

It's not right.

 

 

[BRG]

Rename it Ausgas.  Job done.