View Full Version : Fuel


c170673
08-06-2003, 02:28 AM
This may have been discussed before, but I am too lazy to do a search.

Does anyone know for sure that the car will run on normal Unleaded in the UK?

Chris

morganrogers
08-06-2003, 02:41 AM
Dunno - but if it helps, the original RX7 used to like 2-star fuel , and then unleaded when 2-star stopped.

I vagueally recall something about the rotary having a very low octane requirement.
Of course they have changed the compression ration and stuff in Renesis so maybe...

Oh hell , I dont know !

Perhaps one of our Yank/Jap friends can enlighten us ?

(Notice I didn't suggest 'let's ask mazda' ) ;)

The Ace
08-06-2003, 02:47 AM
Although I dont know the requirements, I would like to say that rotaries are more "sensitive" towards detonation than piston engines, so preventing detonation is of paramount importance.

However, only the modified FDs needed high octane unleaded (more than 96-98Oct), and that was because of their wild variations on A/F ratios through the RPM range. The N/A FCs rarely needed anything more than 89, so since the Renesis is far more advanced engine than the 13B, I'm assuming it will run just fine on low octane gas (like 89-90Oct)

c170673
08-06-2003, 02:49 AM
I recall on the Australian threads their cars will have to use Premium Unleaded, I think this is because the quality of their fuel is worse than european fuel.

Chris

Lock & Load
08-06-2003, 05:07 AM
Shell optimax at average of 90 cents per litre in australia with a 98 octane rating level.

The Ace
08-06-2003, 05:09 AM
Originally posted by Lock & Load
Shell optimax at average of 90 cents per litre in australia with a 98 octane rating level.

Damn :eek:

In Greece, the same gas (Shell V-Power 99+) costs more than 1,1E per litter.....and in Belgium its even more expensive (although here almost everyone drives diesels)

RobDickinson
08-06-2003, 05:11 AM
I've heard conflicing theories on this.

US use lower octane fuel than us normaly, Japan higher.

IF optimax like fuel makes a diff I may use it, not 100% yet tho, its gona cost a bomb more in fuel than my old car whatever - but you cant always get higher octane fuel - I wont mind mixing from time to time anyhow.

unleaded is 82p , optimax is what 88p?

sixspeed
08-06-2003, 06:17 AM
Where do you live!?

Round here Unleaded is around 73-74p and Optimax about 77.9 to 79.9...?



-andy-

c170673
08-06-2003, 06:22 AM
You can check average prices for your area of the country by following the link here (http://www.theaa.com/allaboutcars/fuel/index.html) wou can alos follow th link on that site to e more localised search but you have to register.

Chris

ChrisW
08-09-2003, 08:25 AM
I can't remember which thread it was in, and I'm also too lazy to do a search, but I remember there was a posting which quoted from the US users manual. It said that the car needed 96 RON or higher for best performance but could use lower rating.

This is tantalisingly close to UK Premium (95 RON). I wonder if we would see any improvement from using Optimax?

rx-8@mazda
08-09-2003, 09:16 AM
Tried and tested:
95 RON is perfect.
98 RON is ok but not necessary
Optimax = plain stupid

MarkW
08-09-2003, 09:24 AM
Originally posted by rx-8@mazda
Tried and tested:
95 RON is perfect.
98 RON is ok but not necessary
Optimax = plain stupid

Optimax is 98RON :confused: :confused:

rx8 - smooth!
08-10-2003, 08:28 PM
There is a warning sticker on the fuel filler cap saying that the minimum fuel requirement is 95RON.

How do I know?

I own one!

Lock & Load
08-10-2003, 10:47 PM
Mark w shell optimax which is rated at 98 ron is sold here in australia at approximately 90 cents per litre , i find this to be the best for running the rx8.

crabacle
08-11-2003, 02:09 AM
I asked the UK Marketing fellow on Friday at Leeds regarding this. He stated that it will run happily on normal unleaded. :)

morganrogers
08-11-2003, 02:21 AM
Yay ! Good news then.

Always thought it would be normal unleaded - which is good.
Part of my in-my-head justification for the thirst of the rotary is that the fuel will be cheaper than my current ride (which requires optimax). OK , so it is only 7%ish difference but it all helps !

7% is another couple less MPG I can afford :)

Currently see ~32mpg on optimax.
Looking at the reports from the US , the RX8 should give me 25-27 on the sort of runs I do (all 60mph M1 commutes) so pretty good really....