Super Unleaded

Not too many petrol stations sell this in my neck of the woods.Am I correct in thinking that 4* LRP is something completely different to 97ron SuperUnleaded ?Cheers, Tim

LRP will be at least 97 RON but also has an additive to do the same job as the lead. Value seat protection etc.The lead is replaced by potassium in LRP not sure if this would polute the catalyst in the same way (if indeed you still have one).Can’t say I notice a big difference between unleaded and super. Optimax does seem to help though.Bottom line is LRP is effectively 97 with stuff in and the stuff may do bad things to modern engines.

Cheers MatthewThought as much - if I’m stuck I’ll put a fivers worth of bog-standard unleaded in.Thanks, Tim

TimboI agree - only use unleaded. Personally, I try to use Optimax all the time.The following link may be of interest:

Pesky - thanks for that.Checked the nearest Shell to me and it’s about 25 miles away.Good excuse for a blat over to Chesterfield now and again though [image][/image]Mind you - I’m getting less than 25mpg [image][/image]Cheers, Tim

EVO Mag have an article on Optimax this month. They ran their Civic typeR, Jag & M coupe on the stuff for 1500 miles and then looked at the valves before and after.It looks like Optimax does help, although not using supermarket fuel is also an advantage.

The article was interesting and I certainly think Optimax improves the drive but I wonder if the valves would actually be worn by the additives (the problem the old Shell Formula caused I believe)?If it cleans that much crap off that quickly it’s got to be pretty powerful stuff!Just a thought.Ian [image][/image]

Ian,I have been using 100 Octane racing fuel in my Kart (it is required for the champs as control fuel) - that stuff is extremely nasty and eats away carburettor diaphragms, seals etc in no time at all… Optimax is not so nasty on the said bits but still causes problems. Could be down to the additives I guess, but maybe the octane rating? I’d hope that it wouldn’t cause any valve damage tho’ especially to engines that are high performance anyway. Btw - you’re right, its time to organise another pub get-together! I’ll have a think about dates & maybe another venue… [image][/image]Steve