Knock fix with Australian Fuel 98/100 RON

[steve99]

Originally Posted by TheRoadWarrior

Curious: is Australian 98-100ron fuel the same as the UK octane rating?

Over here the highest octane rating available is 99ron from tesco.

Octane ratings are done in some kind of contraption in a lab as I understand it. So fuels can perform differently in the real world, even in same country the performance of a say 98RON fuel can vary as far a knock resistance goes.

Best to just log for knock and see which brand of fuel is best.

[tmichel]

Hey Steve before you changed to 85 which 98 were you running?

[steve99]

Originally Posted by tmichel

Hey Steve before you changed to 85 which 98 were you running?

Used Shell V Power 98 , seems better than Caltex Vortex 98 for knock.

however United 100 octane seems to be the best if you can get it.

[tmichel]

Originally Posted by steve99

Used Shell V Power 98 , seems better than Caltex Vortex 98 for knock.

however United 100 octane seems to be the best if you can get it.

Got Shell in it at the moment will try United in the next tank, also loaded your map now on OFT but will try the fuels first as you suggested.

[Wayno]

Shell used to always put extra shit in their fuel to "clean your engine" and BP was more potent. I haven't tried Shell for 10 years!

[tmichel]

Originally Posted by Wayno

Shell used to always put extra shit in their fuel to "clean your engine" and BP was more potent. I haven't tried Shell for 10 years!

I used to run BP in my XR5 as it gave it the most poke but Shell was a close second.

[tmichel]

Missus rang me today to say how much smoother the car is running now , thanks OFT and Steve.

[steve99]

Added some more info to original post for Intake Air Temperature vs Ignition Timing retard tables if knock is temperature related.

[tmichel]

http://datazap.me/u/tmichel/98-bp-27...-5-6-7-8-11-12

Steve can you please have a look at this one flat rd BP98 3000 to 7000 and I think I measured what I should?

[steve99]

Originally Posted by tmichel

http://datazap.me/u/tmichel/98-bp-27...-5-6-7-8-11-12

Steve can you please have a look at this one flat rd BP98 3000 to 7000 and I think I measured what I should?

Hmmmm looks a bit ordinary IAM 0.52 FLKC over 2 degrees correction

what map are you running V2 ? are you stock or on stage2 man/auto ?

definitly try shell vpower 98 or preferably united 100 ron that BP fuel does not appear to be much good.

If your stock manual i can send you a map for Shell 98.

[tmichel]

Yep running V 2 on stock manual if you could send the map for Shell that would be great

[steve99]

Originally Posted by tmichel

Yep running V 2 on stock manual if you could send the map for Shell that would be great

OK attached is ROM for 98 RON Its based on OFT V2x tune with some timing pulled at top end and at low/med rpm high load due our crappy fuels.

also has IAT vs Ignition retard increased for our high temps and added some ignition retard if Coolant temps get to over 100C (212F).
Also has couple of mods to high rev cold start to quieten it down less MAF adjustment less Ignition retard and less RPM at cold startup.

[Wayno]

In case you haven't heard, United is discontinuing P100 very soon

[steve99]

Originally Posted by Wayno

In case you haven't heard, United is discontinuing P100 very soon

you can make your own P100. Add 6 litres of E85 to a tank of 98 RON (ethanol free stuff)