98 or 95 RON?

[Gafferlicious]

Ok, so upon reading the manual I have figured out that 98 RON is recommended for track use (not wanted yet, I need to do the tvrcc advanced driving courses first before I consider a visit to a track somewhere g )......and "either/or" 95/98 for normal day use.

So my dastardly plan (based on the fact that don't ALL engines benefit from a bit of the expensive stuff now and again?) is to alternate between them.

....every 7th or 10th fill up I'll do 98 RON with 95 RON in between.

^^^ Is there ANY benefit at all to doing this?
Should I just stick to 98 RON for everyday use? Or stick to 95 RON?

What do you peeps do/recommend?

(so far I've filled'erup with 98RON first fillup and 95 for the second).

[glow worm]

Always put Shell V-Power (98 RON) in mine.

[BatleyBoy]

Tesco 99 RON

[D14 AYS]

glow worm said:

Always put Shell V-Power (98 RON) in mine.

[2 sMoKiN bArReLs]

Why bother with the 95? (other than possibly easier to find).

[S6PNJ]

I ran my 5.0ltr Chim on 95 for 3.5 years and I've been running my 4.0 Tusc for 3 years on 95. The SP6 ECU cannot 'auto-adapt' to the change in RON in the petrol so unless you have your engine mapped for the 98/99, you are not getting the full benefit. There may be fringe benefits if your timing is set close to the 95, or the 95 RON fuel is a bit rough, but other than that I wouldn't say there is much in it (other than a few pence of course!)

[onny]

Having the Tuscan in hotter climates, I've found that running 98 Ron petrol (Optimax) keeps the car running at a lower temperature than running with 95 Ron petrol. It makes a big difference when you're stuck in traffic and its 30+ outside.

[jeast]

After mine was re-built I was told to fill up with v-power every fourth or fifth refill as the engine would run perfectly well on 95 and every foutrth or fifth fill up on v-power was often enough to realie the benefits of any additives etc that v-power contins.

[WhyTwo]

D14 AYS said:

glow worm said:

Always put Shell V-Power (98 RON) in mine.

Yep or any other 98 RON if I can't find a Shell garage. For the sake of a few quid each time why wouldn't you?

[NTEL]

Tried 95 in my Tus 2 when I first got it. Heard some very slight pinking so filled it up with V power. Been on either V power or Ultimate ever since.

[Hexhamhc]

We always stress to owners of Speed Six engined cars the importance of running the car on premium higher octane fuel. Because the rear cylinders are virtually inside the car with you they have a tendancy to run hot, on most cars if the engine management detacts pinking it retards the timing via the 'knock sensor', TVRs do not have knock sensors so if they pink they can potentially just carry on pinking until damage is done. Don't do it, for the sake of a few extra pence per gallon, use the 'good stuff'!! The cars do seem to run better on it anyway and quite a few owners reckon that the mpg returns are better too!
Hope this helps and best regards to all, Tony

[softtop]

Hexhamhc said:

We always stress to owners of Speed Six engined cars the importance of running the car on premium higher octane fuel. Because the rear cylinders are virtually inside the car with you they have a tendancy to run hot, on most cars if the engine management detacts pinking it retards the timing via the 'knock sensor', TVRs do not have knock sensors so if they pink they can potentially just carry on pinking until damage is done. Don't do it, for the sake of a few extra pence per gallon, use the 'good stuff'!! The cars do seem to run better on it anyway and quite a few owners reckon that the mpg returns are better too!
Hope this helps and best regards to all, Tony

Hello Tony

Any dates for HHC Croft track days? Do the recent events about noise affect this? Thanks S

[PDtvr]

NTEL said:

Tried 95 in my Tus 2 when I first got it. Heard some very slight pinking so filled it up with V power. Been on either V power or Ultimate ever since.

Same here

[Chim326]

I run what ever Super unleaded (not Tesco)is available for my Tuscan, was also informed by very reputable Cosworth engine builder that for my Sierra Cosworth Mapped and chipped to 330 bhp being original 4star that the top half of the engine would last a lot longer as the valves would run cooler if super unleaded is used because the extra lead that is in super unleaded helps lubricate the valve stems and prevents the edges from over heating/burning which is caused by running to lean on the lower octane 95 ron. If I used 95 then the max power 1.8 bar boost was unachievable as it would misfire and loose power before max rpm reached.
I thought you could only get 97 ron from the forecourt including Shell v power/optimax.
My Chimaera (standard 4.0)and Sierra C misfire at max power if Tesco 99 ron is used, Only used it once.