4 star in an '83?

hello all,after finally finding somewhere to work on my newly (ok september) aquired mk1 im gettin worried that it will only use 4 star fuel,it a 1.1 formel e by the way. i have no idea if its been fitted with something to make it except good old unleaded,all i know is on the history folder someone has written 4 star only,but this looks to be written years and years ago so may not be relivant.
anyway i can suss this out without damaging the engine by using unleaded?!?!
thanks in advance,help is GREATLY appreciated

Simon

Your engine will run fine on unleaded, if it pinks under load, slightly knock the distributor back until it stops

The C formel E and GTI need super unleaded (higher octane), because they are higher compression ratio than the other engines. Back in 1983, the recommendation was 4 star due to its higher octane rating.

But you can still run both on unleaded albeit with a slight loss in power

Cero said

But you can still run both on unleaded albeit with a slight loss in power

You can but you shouldn't. Its okay as a one-off (say if you're in a remote location and can only fill up with unleaded) but long term, will cause issues. Hence why the manufacturer recommended the minimum octane rating of the fuel; and why super unleaded exists.

Sorry Paul I agree & disagree with your answer - yes you could cause issues but could and would are a long way apart - my 8v 1.1, 8v 1.8l & 16v 2.0l all have run strickly unleaded since 1987 or so. Heads have been off for oil leaks, modifications to breathing etc but I've never had any issues with unleaded fuelling, maybe just lucky  :dontknow:  In the 'old' days then yes 4 star or super would have been 1st preference but I wouldn't be paying the extra now-a-days just to gain 5bhp unless on a track day, but then again I don't tend to drive as I used to do. I think every engine has it's own tolerence and if it will run on unleaded without issue then leave it alone.

The 1.1 Formel E was designed as an economy version of the engine with higher compression and ignition settings to match. It was designed to run on 4-star (98 octane?). Running on normal unleaded (95 octane) would in theory not be as efficient and could potentially cause damage to the engine.

If it was mine I'd stick Vpower/Opitmax (97/98 octane) type fuel in. The extra few pence per litre should be covered by the extra few MPG you should get over normal unleaded.

thanks guys,thats good news i think,although with the price of petrol at the moment i better start saving for all that super unleaded. on another note,whats the expected mpg from my 1.1 formel e?presuming the engines running sweet etc

If everything was in tip top order I'd exepct to see 40+ poss even breaking the magic 50mpg on a long runs.

So much depends on how, where and when you drive.

If you drive it like a 17 year with his 1st car, across a busy town for only a few miles, in winter, with 3 passengers and luggage you'd struggle to get near 30mpg. Hammering down the motorway at 95 would prob see similar results. A long gentle cross country cruise with no passengers on a summers weekend morning could see 50mpg+.

ha ha good job all my driving is long gentle cross country trips. 50mpg would be ideal,have just ordered quite a few parts from gsf to get the enginerunning as sweet as poss, service kit,new distributor cap,thermostat, so touch wood she will be running like a dream. now to sort those gear linkage bushes........ cheers guys

97 ron will be fine in there, modern fuels are plenty good enough. the unleded was recommended at the time simply because thats all you could get.  it doesnt need the lead additives either. even k-jet gti 8v/16v are fine on 97ron petrol, no pinking when ragging it unless you go way beyond the factory timing marks, my 16v were both fine at 8 degrees advance

necropost alert….

i have a 1.3GF and run it on supermarket unleaded, will this give me any issues later on? it has 60k on the clock.

what about these lead additives or running it on v power?

-z

Water cooled engines from I think 1974 will run no problems with out leaded petrol, they are already fitted with harden valves so don't need the lead in the petrol to protect them from wear.

My 1978 Mk1 Scircco will run on old 2 star petrol straight out of the factory if needed (showing my age remembering 2, 3 and 4 star petrol!) so I just use normal 95 RON unleaded no problems but use super 97 or higher RON unleaded in the Mk1 Golf GTi.

ahh ok, thanks for the info!