[steak_knife]

SuziBlu wrote:

105 octane

Don't forget that the government is giving a large slice of the bill so as to get more people onto gas.

Don't know why thay want us to use LPG as it a bye product of making petrol, You still need to refine crude to get it!!

[SuziBlu]

Its far less polluting.

[Santos]

55c a litre maybe? if you can get 8km+ per litre you would be far ahead of any 1.3l petrol sierra in the game

[steak_knife]

SuziBlu wrote:

Its far less polluting.

So you have billion's of Lt's of petrol that won't be sold, so in effect petrol will be a bye product of Lpg, what will thay do with that? same as thay used to with Lpg, burn it.
Don't make scene to me..

[MacDaddy]

Wow really !

No wonder my 202 red motor with mild cam, had plenty of grunt ! he he...

Yes you are right about the Govt chipping in, but even the smallest LPG tank, would take up heaps of room on a Sierra or early Vitara, a GV would not be such a problem... and i think you still have to use the petrol once in a while to, to lubricate the engine, if it was a case of not having to use petrol anymore, then the old petrol tank could be taken out, and a LPG tank put in its place... i wonder if thats possible with alloy engines ?, hmmm....

[SuziBlu]

yes, as all gas systems that I know of, start on petrol, only for a few seconds, then turn to gas.

[laurie]

Santos wrote:

55c a litre maybe? if you can get 8km+ per litre you would be far ahead of any 1.3l petrol sierra in the game

8km+ per litre i'd be peed off if my economy was that bad.
currently 9.3 and not happy about that.
i would never use e10. cheaper per litre but less power
so more litres needed. i only run 95 octane as ive found it works best
for the $

[SuziBlu]

er, id say that 8l per 100 is stunning.

Do you say 8km per liter, which is different to 99% of OZ, or 8l per 100 which is the standard.

huge difference.

E10 is a big power gain if you tune it well.

IF ethanol is a power loss, why do the super horsepower drag cars run it instead of petrol.

Maybe they are all bone heads.

[losfer]

SuziBlu wrote:

er, id say that 8l per 100 is stunning.

Do you say 8km per liter, which is different to 99% of OZ, or 8l per 100 which is the standard.

huge difference.

E10 is a big power gain if you tune it well.

IF ethanol is a power loss, why do the super horsepower drag cars run it instead of petrol.

Maybe they are all bone heads.

super big horsepower drag cars also use short exhaust runners , if you use the same setup on a street car you would lose power through the lack of backpressure / cylinder scavenging. they are designed to run on these fuels and exhausts , you will find they have a very small valve overlap , and do not require backpressure or cylinder scavenging to get the job done (im no drag car engine builder but this is my theory behind it)

high octane fuels cause a more controlled , slower burn rate , it ignites over the whole power stroke , lower octane fuels have a faster burn rate , more like a spontaneous combustion.

a lot of cars that were released over in japan had much higher compression ratio's than their counterparts that were released here. high compression engines tend to "ping" when too low octane fuel is used (as with a standard compression engine with lower octane fuel available here), the availability of high octane fuel at_the_pump (100 RON +) in japan is common , and is almost unheard of here (especially since they took away v-power racing)

[SuziBlu]

lack of back pressure means lower power, er, mkay.

Strange.

[losfer]

SuziBlu wrote:

lack of back pressure means lower power, er, mkay.

Strange.

you are quite welcome to prove me wrong ..

[SuziBlu]

Could not be bothered.

A hundred years ago, engines needed back pressure, now, they do not.

Valves have come a long way.

[losfer]

why bother with headers , why dont we all just run a straight pipe out from every exhaust runner like top fuel drag cars ...
headers , or extractors , on a conventional ICE engine are made so that every pulse from every exhaust stroke can converge and create some backpressure , so that while the exhaust valve is open , and the intake valve is starting to open , that no exhaust gases can enter into the intake stroke and the fresh charge of air and fuel cannot exit through the exhaust valve.

[SuziBlu]

lol yea ok

[losfer]

SuziBlu wrote:

Could not be bothered.

A hundred years ago, engines needed back pressure, now, they do not.

Valves have come a long way.

are you saying that we dont need backpressure ?
every exhaust shop should stock only 3 inch pipe in your perfect world.

i beg to differ.

[Santos]

Top fuel drag with methanol not ethanol, if you want to read a pro-ethanol rant jump on outers type my name as author and search ethanol

As for # kms per litre thats how i do it. i tend to fill up at 220-290 kms, i divide the odometer kms by the amount of litres i put in. I would only be wasting time trying to then convert that to 100km brochure advertising figure.

since most people average 9-11kms per litre (factory new is like 12.5) getting 8kms out of lpg would be what i think would make the effort worthwhile (given the govt incentive too)

Best case scenario on petrol 12.5km/L = $1.15 ( 9c a km)
Average scenario petrol 10km/L = $1.15 (11.5c a km)
Lpg 8kms = 55c (6.8c a km)

thats going off 91 octane average in my area it fluctuates between 1.07 and 1.20

[SuziBlu]

Thats what Im saying.

Manufactures use small diameter pipe coz its cheap.

Back pressure makes things quiet.

Less back pressure means more power, more noise.

No modern engine requires back pressure.

that was from ages back to stop valves from burning, nothing else.

[Santos]

i'm with suziblu here, the tuning of exhaust pulses on extractors is something seperate to backpressure.

3 inch pipe has its drawbacks, lieke the amount of room it takes up, and most cars cant retro fit it without serious speed bump issues.

Jumpo redlinegti.com and you will see heaps of 2.5" and higher 1,3l with powerfigures to back up the improvement... they too spend hours arguing with dated tuning theories of the shop owners.

[losfer]

the guys running 2.5 inches plus on redline are forced induction !!!\\

i think we need a new topic for this debate , it has gone well past the octane debate !

santos , my nick on redline is n0madic , come and say hi sometime !

[coilyzook]

to get L/100km you

1. devide Litres used by km driven
this gives you how many litres used every Km
2. times that amount by 100
this gives you L/100km

nice and easy

[Santos]

Santos = Lattecruiser, and i seem to recall NA 2.5' systems... anyway i will look up the info on the exhaust pulse scaveging and backpresure
I think it in the 3rd ed of ' 4 stroke performance by A. Bel

[Santos]

coilyzook wrote:

to get L/100km you

1. devide Litres used by km driven
this gives you how many litres used every Km
2. times that amount by 100
this gives you L/100km

nice and easy

lol true but involves one extra step, km/L IS QUICKER