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RedB
7th June 2007, 10:33
Is it possible to mix fuels as i have heard sum bullsh*t on this and was wondering? The fuels would be 95octane unleaded and 97ish octane v-power or similar. Surely this would be the same as adding octane booster tho and wouldnt damage engine or car??

Any help or advice would be spot-on cheers :y:

KamRacing
7th June 2007, 10:55
you can mix fuels with different RON's absolutely fine as long as its petrol :D Otherwise you would have to drain your tank if you changed to v-power from regular!

Karl
7th June 2007, 10:56
mixing your fuel like that doesnt do your car any harm whatsoever.
i do it all the time.
always good to fill up with 97/99 every now and then.

AXracing
7th June 2007, 11:21
As said mixing is fine. But don’t forget the Saxo was only ever intended to run a cat piss. So sticking good fuel in a standard or near to standard engine does not do much apart from cost you more.

Barry123
7th June 2007, 16:46
As said mixing is fine. But don’t forget the Saxo was only ever intended to run a cat piss. So sticking good fuel in a standard or near to standard engine does not do much apart from cost you more.

I worship you.

i say it time and again and I just get ignored.

CampDavid
7th June 2007, 16:56
VTS lump will run 95-98 ron and can adjust timing to suite.

Pricier fuels like V power and Ultimate have better cleaning products in and help keep injectors clean

Higher RON is a GOOD THING on track, less det and a much lower chance of melting pistons/valve/other assorted engine malark. Worth the £2 for the tank? Yup

You'll also find that cylinder liners will last longer with more expencive fuel. BMW had a feck load of trouble a few years ago because they assumed that people who bought 328i and 540i models would use super unleaded. In the UK we're tight and mostly don't bother so engines started to go bang. BMW replaced loads of engine and changed the liners from nikle to aluminium.

95 RON is fine for most models, I'd always stuff V-power in once in a while though to clean it all up.

V power is the fuel of choice for my VTS and the only thing it drinks most of the time. But then I have no clue about cars/engine etc, I just like wasting my cash.

Barry123
7th June 2007, 17:09
BMW replaced loads of engine and changed the liners from nikle to aluminium.

not doubting you dave but as im a bit of a material science goon im interested in why replacing nickel (which has a high elevated creep resistance) with aluminium (which is comparitively uber shite at elevated temps) has been done. seems counter intuitive innit...

do you have link or anything related to the retro fits so i can fill my mind with more useless bollocks?

frankie
7th June 2007, 17:11
i did this once and it made my car go gammy. but it was shiity tesco stuff no. bp ultimate or v-power.

CampDavid
7th June 2007, 17:14
For you Ad

http://www.bmwworld.com/engines/nikasil.htm

Barry123
7th June 2007, 17:19
For you Ad

http://www.bmwworld.com/engines/nikasil.htm

thank you kindly :y:

Toad
7th June 2007, 17:20
VTS lump will run 95-98 ron and can adjust timing to suite.

Pricier fuels like V power and Ultimate have better cleaning products in and help keep injectors clean

Higher RON is a GOOD THING on track, less det and a much lower chance of melting pistons/valve/other assorted engine malark. Worth the £2 for the tank? Yup

You'll also find that cylinder liners will last longer with more expencive fuel. BMW had a feck load of trouble a few years ago because they assumed that people who bought 328i and 540i models would use super unleaded. In the UK we're tight and mostly don't bother so engines started to go bang. BMW replaced loads of engine and changed the liners from nikle to aluminium.

95 RON is fine for most models, I'd always stuff V-power in once in a while though to clean it all up.

V power is the fuel of choice for my VTS and the only thing it drinks most of the time. But then I have no clue about cars/engine etc, I just like wasting my cash.


I started a thread on a similar subject the other day, but didn't get a final answer really...

I had my car mapped by Chipwizards and at the time, it was running on Shell Optimax, I think it was advertised as being 98RON, can't remember... Anyway, I run my car on BT Ultimate now, time and time again, I've tried filling up with the newer Shell product, V-Power, but it doesn't run as well. It runs smooth like, but it doesn't have the same response as the BP. Do you know why this might be? :panic:

Cheers! :drink:

RAFkev
7th June 2007, 17:41
hmmmm. this "Shell vs. BP" and which is better could make all the difference on the 0-60 strip!

RedB
7th June 2007, 19:32
I started a thread on a similar subject the other day, but didn't get a final answer really...

Cheers! :drink:

Just popular i guess :p

lol cheers for all the help saxp-ers, some knowledge out ther :y:

CampDavid
8th June 2007, 07:46
I started a thread on a similar subject the other day, but didn't get a final answer really...

I had my car mapped by Chipwizards and at the time, it was running on Shell Optimax, I think it was advertised as being 98RON, can't remember... Anyway, I run my car on BT Ultimate now, time and time again, I've tried filling up with the newer Shell product, V-Power, but it doesn't run as well. It runs smooth like, but it doesn't have the same response as the BP. Do you know why this might be? :panic:

Cheers! :drink:

I have exactly the same issue (or did have until my ECU failed!)

The honest answer is I don't know.

Some cars respond better to different fuels and it's a bit odd how they react. My one started to be loads more ecconomical when running German 100 RON V power but never really gets on with the UK stuff so well. When I get the map put back on mine I'll try BP ult to see if it now prefers that!

Toad
8th June 2007, 11:09
Intersting to know that I'm not the only one... Cheers for that.

The only thing I could think of was that the V-Power (99 RON) was a little too high, hence loss of power, as in thoery, too high of a RON fuel would lose you power would it not? But if you have noticed that the 100 RON stuff was working well, them I'm a little lost. Perhaps it's just the quality of the drop so to speak, and similarly to what you've already said, it's how your engine deals with it...

Barry123
8th June 2007, 11:59
Intersting to know that I'm not the only one... Cheers for that.

The only thing I could think of was that the V-Power (99 RON) was a little too high, hence loss of power, as in thoery, too high of a RON fuel would lose you power would it not? But if you have noticed that the 100 RON stuff was working well, them I'm a little lost. Perhaps it's just the quality of the drop so to speak, and similarly to what you've already said, it's how your engine deals with it...


I was under the impression the standard ECU couldnt adjust the timings to suit anything higher than 97RON. In most cases the ECU wont adjust the map till 2-3 tank fulls of a new fuel being used. using higher RON's should'nt lose you power you just wont get maximum out of it.

Toad
8th June 2007, 12:10
Are you sure? The higher the RON, the less volitile the fuel is, so I assumed if it was being detonated under the same pressure (a non-tuned / standard compression engine) it might have consequences... Maybe not then...

Barry123
8th June 2007, 12:15
Are you sure? The higher the RON, the less volitile the fuel is, so I assumed if it was being detonated under the same pressure (a non-tuned / standard compression engine) it might have consequences... Maybe not then...

probs run rougher but otherwise i cant see an overall reduction in power tbh

Toad
8th June 2007, 12:31
Google time... Hehe.

Barry123
8th June 2007, 12:32
Google time... Hehe.

my thoughts exactly. just try to filter out the rubbish from modern sports car owners... the cars ECU will no doubt have a wider RON acceptability than the saxo's

Toad
8th June 2007, 12:51
Slightly off subject... When then likes of Wayne at Chipwizards maps Saxo's / 106's, does he alter the ignition timing? Does he do anything else apart from setting the fuelling throughout the rev range?

Barry123
8th June 2007, 12:54
I'll let campfeatures answer that one as i honestly dont have a clue. although i thought timings was one of the key factors in mapping :)

Toad
8th June 2007, 12:57
True, but if the car alters that anyway, (as mentioned earlier) where does that leave you???

Barry123
8th June 2007, 13:02
True, but if the car alters that anyway, (as mentioned earlier) where does that leave you???

well the ECU (as far as im aware) cant adjust timings beyond 97RON - as the map on the car doesnt cover fuel beyond that 'RONage'

when you put in (an) uprated cam(s) then the timings will be out of sync with the position of the valves and so the point at which the fuel and air enters the cylinder differs from where the ECU expects it to be. hence why the timings then need to be adjusted (ECU remapped).