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Discussion Starter · #1 ·
What petrol do you put in your V5?

Do you use normal unleaded, super, optimax, etc.?

Do you change the type of petrol used depending on length of journeys?

The previous owner told me to use super unleaded, but I could only find unleaded and put that in - now the car seems sluggish [:(]
 

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The V engines prefer Super, be that 97 or 98 RON. They have very high
compression ratios so need it to prevent pre-detonation or 'pinking'.

It will run ok on 95 (normal) but I personally wouldn't for long periods.

I always fill up with Optimax or Esso super if I can't find a shell station.
 

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It doesn't really matter to be honest, only with highly tuned turbo's should you use Optimax as it does help prevent "DET" the gains on your V5 through using Optimax would be next to nothing, I have tried optimax on non-turbo cars and it's no different to normal Unleaded its all psychological

Same applys to Diesel Using BP Ultimate over normal Diesel makes no difference at all to power but the car is less smokey on Ultimate to standard Sainsburrys stuff.

Bottom line is waste of money with non-turbo petrols.......for turbo's I found I could run a little more boost on optimax.....and for Diesel its worth it as you don't get as much soot out of the back
 

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The V engines prefer Super, be that 97 or 98 RON. They have very high compression ratios
Not as high as the 1.6 16V units though [:|]

My last 5 tankfuls have had 2x STP fuel injector cleaner, 2x STP octane boost (they come as a twin pack, one bottle of each) and 1x Nitrox octane booster mixed in with Optimax, boy that octane booster stuff really works. Car doesn't feel any faster but can really push it hard and it won't make those nasty rattling noises [:S]
 

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It doesn't really matter to be honest,
only with highly tuned turbo's should you use Optimax as it does help
prevent "DET" the gains on your V5 through using Optimax would be next
to nothing, I have tried optimax on non-turbo cars and it's no
different to normal Unleaded its all psychological

Same applys to Diesel Using BP Ultimate over normal Diesel makes no
difference at all to power but the car is less smokey on Ultimate to
standard Sainsburrys stuff.

Bottom line is waste of money with non-turbo petrols.......for
turbo's I found I could run a little more boost on optimax.....and for
Diesel its worth it as you don't get as much soot out of the back
Even N/A engines pink you know. Especially ones running 11:1
compression on poor quality fuel. If the engine senses the pinking it
will retard the timing which means you lose power.

Check the fuel filler cap or the manual for the V5. It states super is best to use.
 

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It doesn't really matter to be honest, only with highly tuned turbo's should you use Optimax as it does help prevent "DET" the gains on your V5 through using Optimax would be next to nothing, I have tried optimax on non-turbo cars and it's no different to normal Unleaded its all psychological

Same applys to Diesel Using BP Ultimate over normal Diesel makes no difference at all to power but the car is less smokey on Ultimate to standard Sainsburrys stuff.

Bottom line is waste of money with non-turbo petrols.......for turbo's I found I could run a little more boost on optimax.....and for Diesel its worth it as you don't get as much soot out of the back
Even N/A engines pink you know. Especially ones running 11:1 compression on poor quality fuel. If the engine senses the pinking it will retard the timing which means you lose power.
Check the fuel filler cap or the manual for the V5. It states super is best to use
Have to agree, even if mine is a V6 and not a V5. 97 or less fuel is no good for any car, unless its an old 1.3 or something and then u will probaby need to run higher octane fuel so as not the burn out the valve seats!

At the end of the day there is a reason why N/A race cars use really high octane fuel and its not to gain a couple of extra BHP, its so the engine doesn't predetinate itself to death or start melting pistions and valves. Priciple is the same on road cars, just a little less severe!

always use 97ron or higher the couple of pounds extra on a tank full isn't worth killing a two thousand pound engine.
 

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I gotta say i dont really notice the difference between the two fuels. I dont know if its just that my car probably done its previous 40k on 95 RON but super just makes no noticable difference. In my old PD150 the ultimate diesel did make a difference though and the Mini Cooper S i had before that it again made a big difference.

I would normally chose it but recent fuel price hikes put me off. The prices are dipping agian so might give it another go.
 

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Discussion Starter · #13 ·
Ok guys, I'm a bit confused. Is the idea of optimax/ultimate to get more power from the engine or make sure the engine is running efficiently.
 

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Both, they go hand in hand.

A more efficient burn from a higher octane fuel means you get better economy and healthier combustion/cleaner engine.

The higher stability of the 98RON fuel means it can run more advanced timing that gives more power/better throttle response.
 

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Discussion Starter · #15 ·
Ok. So should all V5's use optimax or only the ones that have been tuned and are driven hard? [*-)]

In other words, would the average driver, like me, notice anything different when driving around town or on long journeys on the motorway - will it help my engine out by a significant amount?
 

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It only comes down to spending an extra couple of quid on a tank of fuel but if it bothers you, fill up with 95RON.

It won't make your engine go bang but it will reduce it's efficiency and make the combustion less clean.

I use super as I know it does the engine more good that normal unleaded
due to the abnormally high compression ratio the engine has.
 
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