The V8 Owners Forum -

Thats the question, I'm guessing 95 won't be "good" enough?

Hello ?.

I guess is depends upon your use! Urban? Long haul Motorway? Track?

For normal urban motoring you will definitely be able to do all you need with 95 RON.

Don't thrash it and don't overload it. Let it rev freely and change your engine oil every 3000 to 6000 miles according to how it looks and your pocket.

Reset ignition timing to just eliminate pinking (usually 4 to 6 degrees retarded from the book figure making it somewhere around 2 to 4 deg BTDC)) and then reset the CO and idle adjustments for comfortable pootling.

I have written an essay regarding choice of fuel RON but aimed it injection engine.

However I don't see why the ideas and advice therein won't apply to carb engines either.

http://www.vintagemodelairplane.com/pag ... ane01.html

There is oodles of other stuff on my web pages that may be of interest!

Ok, thanks for that. I'll give it a go when the engine is in and see what happens, I was just thinking that being built in the days of 5 star it might well need something other than 95.

Hi
if it is in a light vehicle and you run it through the gears rather than sticking it in 5th and lugging it around without changing gear you should be fine, try and make sure the distributor is in good condition and keep the vac advance working but take a couple of degrees out of maximum mechanical advance with a sleeve over the little post in the dizzy that limits maximum advance and there should be nothing to worry about.
best regards
Mike

That's a good idea, sleeving the pin - I'll have to remember that.

Mike.

I have a similar C/R on my 4.6. I was always going to use Super Unleaded which is 97 or 98 RON, cant remember?

I have static ignition set at 10 BTDC, using a Eddie 500 carb and have the vac advance set up. Don't know how to do the sleeve mod? I have not started the motor yet.

Should I reset my Static timing to 6 deg?

Thanks Mark

try it, if it pinks at 10 degrees then retard it a bit, really you should set up the advance curve on a dyno.
How are you going to get a 4.6 on Dizzy and a 4 barrel through emissions/sva? surly all the 4.6s need cats?
best regards
best regards
Mike