98 octane fuel

[bossdrew]

hi
I have a chimaera 500, it seems to run better on shell optimax than anything else, problem is where i live it takes half a tank of fuel to fill up... any alternatives and also what do you think about running on 97 octane, say BP fro example...

Does it really make a difference?

[pullingpower]

I've tried BP ultima and Mobil 1. Didn't notice much difference.
I also heard that Shell Optimax can be of varying quality in that it's actual octane rating on the forecourt can be less than 98.

[bossdrew]

thanks for that, will have to try them all to see if i can see any difference

[Don]

I really wouldn't worry. Yes I use Optimax in my Chim (and my BoxS actually) but I don't worry if either gets a tankful of 97 from BP or even a tankful of 95 from any reputable firm.

The only petrol I've found which the Chimaera HATED was some Texaco stuff. It coughed and spluttered (I swear it would have spat it out if it could have) until I was able to refil with some 97 again.

[M@H]

just realising how contraversial that comment was (and not wishing to debate it further) I deleted it..

>> Edited by M@H on Tuesday 8th March 15:32

[Plotloss]

M@H said:

realising how contraversial that comment was I deleted it..

Too late

[M@H]

Bugger Delete the quote though will you, just in case the spies from the Oil companies are about

>> Edited by M@H on Tuesday 8th March 15:37

[jimothy]

bossdrew said:

where i live it takes half a tank of fuel to fill up...

I know the feeling. Where I live it takes half a tank just to buy a pint of milk. And I end up forgetting the milk...

[Nuggs]

Mine runs happily on either Optimax and BP Ultimate.

I always go for the Opti when available though; I think Shell deserve credit for pioneering such an important product for us sports car drivers

I tried running mine on standard 95RON stuff (not supermarket) and it did lumpy farts through town and was a little rough when accelerating.

That said, everyone's car seems a little different...

[Don]

Nuggs said:

and it did lumpy farts through town and was a little rough

Christ. I thought it was horses that did that.

[bossdrew]

Nuggs said:

Mine runs happily on either Optimax and BP Ultimate. I always go for the Opti when available though; I think Shell deserve credit for pioneering such an important product for us sports car drivers I tried running mine on standard 95RON stuff (not supermarket) and it did lumpy farts through town and was a little rough when accelerating. That said, everyone's car seems a little different...

Just bought mine and think it had 95 in it... the fill up with optimax had made it a different beast altogether...

The petrol in the tank may have been sitting for a while, does it deteriorate?

>> Edited by bossdrew on Tuesday 8th March 16:30

[slikk]

bossdrew said:

[quote=Nuggs] The petrol in the tank may have been sitting for a while, does it deteriorate?

Yes.

[ChimBungee]

Interesting, my 99 450 Chim got a red sticker saying that you should use at least 97.
Couldn't help it one time though and had to go for 95 not noticing any difference apart from slightly worse mpg.

Chims had been out before these high-octane fuels hit the market so I asked myself whether the engine specs had changed at some point or someone at TVR just found it a nice idea to make a sticker saying "go for the good stuff"

[IPAddis]

The required octane rating all depends on the ignition timing. Using decent quality petrol with detergents is a must either way however.

Ian A.

[stuartL]

ChimBungee said:

Chims had been out before these high-octane fuels hit the market

Chims have been abnout for some time, but the engine has been about a lot longer. The V8 block she's based on was imported from the states and Rover modified her for UK fuel, in fact 5 Star fuel which was 101 Octane. Not too suprising she isn't too keen on 95.

My 450 hates 95, much prefers Optimax, but I have the same problem nearest garage is 10 miles away. Mind you, it does give me an excuse to burn up the M42 on a Saturday morning

[kev north]

My chimaera 500 loves optimax with performance plus, it gives it 2 more ron, & it runs nice, i wish i never had a cat cause id run it on aviation fuel!!

[jem]

I understand that you can get 100 RON in france, anyone tried it on that?

Do run ron.

J

[snorky]

my chim runs fine on 95 - cannot really tell much difference with 97 or Optimax but can tell diff with V-Power 100 RON...lucky old Frenchies and it was 56p a litre too !

[Saul]

My Chim 500 runs best on Optimax, put in a fuel from manufacturer not mentioned so far which claimed to be high (97) but the car seemed to hate it, not had that again. BP seems fine with 97. Not tried Texaco.

[laz11]

Well my two pennies worth...I had been putting optimax in my pre cat Griff but now having tried 95/98 ron and it runs as good if not better. Maybe it's a pre cat thing?