95 ron and running fine?

[macca]

Anybody tried running on premium unleaded 95 ron? I was really low on petrol on the A1 outside Edinburgh. Being a visitor to the area I had no idea when I would next come accross a petrol station, never mind one that sold Super. Consequently, I had to gamble with standard unleaded, to be on the safe side I just put £15 in to get me to Newcastle and time to find some super. The car ran fine. No apparant power loss or misfiring. I ended up filling the tank with standard unleaded and drove 250 miles on it with no problems. The question is, do I carry on with the cheaper stuff or stop before I do some damage. Anybody know what the consequences are of running on 95 ron?

[TVR Engineer]

Hello Macca, The problem with running a Chimera on 95 Ron is the old problem of pre ignition (pinking) because the Chimera and also the Griff have the timing set well advanced 28 degree`s at 4000rpm on 95 Ron you will get higher temperatures in your cylinders than you want, resulting in burnt piston crowns over long term exposure. Most modern Engines have Knock sensors fitted which can sense pre ignition and retard the ignition when needed, The Engine you have does not have this luxury. It is my personal view it is OK to use 95 Ron if you cannot find Super but don`t make a habbit of it.

[Graham]

I've done the last 15K miles on the cheap sh!t and i carnt find any difference... As long as it doesnt pink there isnt a problem...

[Marshy]

Had mine adjusted for 95. Seems to run just fine, and it's been running like a dream for the last few thousand miles. Yesterday's track day just served to confirm that. I just don't understand why I was pulling away from a 4.2 cerbie on some of the straights...

[macca]

quote:The problem with running a Chimera on 95 Ron is the old problem of pre ignition (pinking

Thanks TVREngineer and everyone else for your comments. Would you agree with Graham that it's OK provided there is no pinking? Marshy, was easy and cost effective to adjust to 95Ron? Shouldn't we all be considering this option, unless you want that extra bit of ooommphh on the track?

[johnwilk]

Which engine are you talking about? Mine is a 5 Litre. Does this need to be converted to run on 95 UL? Which petrol brands do you use? At the motor show Peter Wheeler said the 500 can run well on 95 octane, but still required good quality petrol (BP or ESSO). Any comments? Which petrol brand do you use?

[fourwheeldrift]

quote:Yesterday's track day just served to confirm that. I just don't understand why I was pulling away from a 4.2 cerbie on some of the straights...

Was that the Yellow one or the Blue one?

[THB]

My dealer told me that they run all their cars on 95 - so I thought I might as well

[Marshy]

Mine's a 500, and it's a simple ignition timing adjustment to get it to run on 95 unleaded. Fourwheeldrift: it was the blue one. I was comfortably nailed under braking (I was being a wuss, not wanting to exit the track backwards by going into corners too hot) but I seemed to be getting away on the straights. You were the guy I spoke to with the maroon one, weren't you? Are are you the guy with the blue one? Memory like a sieve me...

[Marshy]

Oh, and it seems to run equally well on any cheapo unleaded I've given it, although I usually stick to Taxarseco, Shell, or, er, Tesco

[richb]

Once saw a Mark Adams (he of tuning the Rover V8 fame) presentation where he said that Texaco or Mobil provided the best quality super-unleaded. Rich...

[55jnj]

"Dirty" fuel i.e 95 instead of 98 risks long term damage to engine. Higher octane actually has a higher lubricating factor to engine & is partly why high performance cars need it. You won't notice any difference on the odd tank fill of 95, only a few pounds saved & the odd fill probably won't cause any problems. Keep doing it though & you could end up with a much bigger bill than you dreamed of.

[GreenV8S]

I've followed a great many discussions about leaded/unleaded, lead replacement, super/normal and so on over the last few years and listened to people who seem to know what they're talking about. The issues that are normally brought up are valve seat lubrication and pinking. The Rover/TVR engine has hardened valve seats as standard so VSR isn't a problem. If it occurs, pinking can be addressed very easily by retarding the ignition slightly. This is the first time I've heard about the problems you mention. How is 95 more 'dirty' than 98, and why would 98 have different lubrication properties than 95? (Or do you work for BP? :-) Peter Humphries (and a green V8S)

quote:"Dirty" fuel i.e 95 instead of 98 risks long term damage to engine. Higher octane actually has a higher lubricating factor to engine & is partly why high performance cars need it. You won't notice any difference on the odd tank fill of 95, only a few pounds saved & the odd fill probably won't cause any problems. Keep doing it though & you could end up with a much bigger bill than you dreamed of.

[fourwheeldrift]

quote: You were the guy I spoke to with the maroon one, weren't you? Are are you the guy with the blue one? Memory like a sieve me...

Me, I'm the one with the Crimson Starmist Red one that was too loud to play. See my profile for a reminder Any luck with the seats, have you been able to find ones with removable cushions? PS should have some pictures up on www.Planet-TVR.co.uk of the day soon. No digital piccies but scanned in I'm afraid but I'll let you know (but I can't remember if I've got any of you on there until I get them back)