Alfa Romeo Owners Club of Australia Forum

General Category => General Discussion => Topic started by: karlo on August 07, 2010, 05:52:45 PM

Title: Correct fuel?
Post by: karlo on August 07, 2010, 05:52:45 PM
Hi Gents and ladies

Can someone please clarify if which type or which the better fuel to be using...

Ive been putting in Mobil fuel premium unleaded (i think the 98) anyway the more expensive one out of the 2...and also adding lead replacement to how ever many liters pumped.

Is this correct? should i be using unleaded and then adding lead replacement? or forget about the lead replacement all together?

someone could get back to me soon as i hope im not doing more harm than good.

Cheers Karlo

Title: Re: Correct fuel?
Post by: wankski on August 07, 2010, 07:30:10 PM
no need.

assuming stock 2.0 alfa nord engine, retard ign 3 degrees from stock and it can take regular no problemo...

octane rating is merely for anti-pre detonation properties, which @ 9:1 compression is no problem...
Title: Re: Correct fuel?
Post by: karlo on August 07, 2010, 07:39:21 PM
thanks for the reply...

but as u may gather im not very mechanically switch on.. :-\.its stock GTV 1981 model

can u translate for me?


no need for lead replacement? and is it ok to use premium fuel? or just got straight unleaded?

sorry....thanks again
Title: Re: Correct fuel?
Post by: dehne on August 07, 2010, 08:41:44 PM
just use 95 and above 98 is best as it has a lub in it
Title: Re: Correct fuel?
Post by: karlo on August 07, 2010, 09:44:59 PM
So no need for the lead replacement?

Been using the optimax herd it's a no go?
Title: Re: Correct fuel?
Post by: Simon Aarons on August 07, 2010, 11:10:23 PM
Hi Karlo,

I use any of the major fuel companies 98 octane. Never had a problem with any and have never found one to be better than the other! This goes for the gtv6 and when i have put fuel in the 2.0L as well. Never used an additive and the car is still running after years of track abuse and Mick not servicing it  ;)
Title: Re: Correct fuel?
Post by: stradale on August 08, 2010, 07:30:03 PM
The lead was in fuel to lubricate the valve's and the valve seat's
Alfas at the time did not have hardened valves seats
If you use unleaded and dont use an additive, over a period of time the valve's and seat's wear and this could be years depending on how long and how fast the car is driven
It shows up when you do a measurement of the valve clearance usually once a year for a road car.
As the valve and seat wear the valve clearance changes.....tick... tick....ticking will increase
Eventually the clearance cannot be adjusted  and new valves and seats are needed
In the eighties there were two petrol choices super and standard super was the higher octane
Alfas like the higher octane fuels if you can afford them use them
Many engines have been rebuilt with hardened valve seats,  If you dont know the history of the engine in your car and don't know if the engine has hardened valve seats, use an additive
the engine will not explode because you could or did not use additives, but over a longer period  you are better off using additives :)  
Title: Re: Correct fuel?
Post by: karlo on August 08, 2010, 08:39:04 PM
Thanks Sportiva.....

ur a champion....understood that one....

karlo
Title: Re: Correct fuel?
Post by: wankski on August 09, 2010, 12:28:11 AM
best bet is to ask your alfa mechanic on their views...

but my opinion is that the 80s gtvs had sufficiently hard seats to not be an issue. i would not use additive... soft seats requiring additive is usually a pre-70s thing with the nords...  i just did a quick search and seems validated by the below:

ALFA ROMEO index

Pre-1965: Ideally fit hardened seats and higher specification valves.

Post 1965, inc Giulia, 105, 1600 Junior, Spiders, 1300/1600/1750/2000, 2000 GTV, Alfasud, 33, Sprint, Alfetta, Giulietta, (up to, but not including fuel-injected models - 75, 90, etc.): Usually necessary to retard ignition timing 3°.

GTV 6, 90: No modifications/adjustments required.

75: Ensure that correct relay is fitted in fuel-injection system for unleaded.

Alfetta Gold Cloverleaf, Bosch Motronic ignition: Very high compression use LRP or octane-booster or lower compression ratio.

from: http://www.vea.qc.ca/vea/articles/unleaded.htm

google nord and unleaded http://www.google.com.au/search?sourceid=chrome&ie=UTF-8&q=alfa+nord+unleaded
Title: Re: Correct fuel?
Post by: wankski on August 09, 2010, 12:38:54 AM
damn google is good:

http://www.octane.ie/forum/attachment.php?s=4805f8af6bc5b03ebcf86e3b13746cff&attachmentid=6169&d=1281226974
http://www.octane.ie/forum/attachment.php?s=4805f8af6bc5b03ebcf86e3b13746cff&attachmentid=6170&d=1281227002
http://www.octane.ie/forum/attachment.php?s=4805f8af6bc5b03ebcf86e3b13746cff&attachmentid=6171&d=1281227042
Title: Re: Correct fuel?
Post by: stradale on August 09, 2010, 01:53:16 PM
Didn't have google in the early eightes , so had to rely the literature of the time
Also was told by the techs at my local and very well respected Alfa dealer that the valve seats in pre 86 model alfas did not like unleaded fuel as directed by Alfa Romeo Australia

So Karlo its your decision  
Title: Re: Correct fuel?
Post by: stradale on August 09, 2010, 07:28:54 PM
Sorry Karlo
I gave you information that might not be correct please ignore my post #6
I ran an alfetta sportiva for 10 years on additives before having the head reconditioned.
I went on information available at the time, I should have saved my money :-[
Title: Re: Correct fuel?
Post by: karlo on August 09, 2010, 08:02:24 PM
No problems....

I didnt know what was correct on incorrect info...sooo it was all the same to me.

thanks to both of u for ur help.