Just wondering what sort of fuel is good for the vintage Beetle?
I had my engine redone a few years back so it can take unleaded fuel.
I find that the best sort of fuel seems to be BP Ultimax 98 Octane. But its expensive.
I've tried Shell's 98 Octane fuel - but for some reason it seems to be my engine run louder or rougher. Is it my imagination?
I've also tried Caltex/woolworth fuel - seems ok...
Any comments?
Does anyone also use additives or are they a waste of money?
The discussion seems to be one that has been done a lot over time. From my research the general consesous was 95 octane or above is good. Avoid E10
(unless you are tuned and upgraded to suit). Lead additives are not necessary due to the heads being used in the bugs being made of material that
suited unleaded fuels. Brands and such are a bit of a public gratification game, you'll get bad fuel when you get bad fuel, the brand on the pump
wont mean anything when water gets in their tanks (see Eastern Creek Caltex) or similiar.
I think higher octane = lower burning temp, therefore more desired by most a/c nuts?
BP 98 octane, I've never had a problem for over the last 10 + years..
stick to what is good and it's been problem free for me..
it maybe a few cents more but WORTH every cent in the long run..
good luck
Our 1970 1600 twin port Beetle was designed for 'Super' petrol that was available at the time, and it runs well on 91 Unleaded fuel. My wife was
recommended to put a tank of 98 in it, and it would not run well at all. The timing and compression ratio was not set up for 98. So basically if you
have a stock 1600 twin port engine 91 is the right fuel, but if you have modified or improved the engine to run on a different fuel, then you need to
use that fuel.
Earlier engines from the 60's had lower compressions again, and back then there was 86 Octane 'Standard' fuel. It depends on whether your engine
has had the compression ratio upped, ad the timing suited to other fuels.
BP ultimate has been the best fuel I found in regards to detonation resistance and power output. Also after may tests on fuel filters and fuel system
components its also one of the cleanest too.
Shell 98 is ok, but avoid small station with low turnover as its a very short shelf life. about 4 weeks. BP is about 6 months.
caltex non safeway vortex is ok, avoid safeway caltex like the plague. Low grade import fuel. Detonation prone and just bad all round.
Also avoid BP 95 premium, I do believe its just 91 with some octane boosting agent. For years i had trouble with it, i had made a little documentation
on that fuel on about site with the problems it causes.
It leaves a heavy fine powdered bright red residue that killed quite a few fuel pumps, blocks filters after few weeks and kills injectors( would mess
up carbs even worse) After 5 years of testing different stations I concluded it was that grade of fuel not any particular station. So avoid it like
the plague also!
Can't say anything about mobil other they were good when they existed many years ago.
7/11 I heard was really bad.
Apco also said to be shit.
United as far as I know is alright, my friends get best mileage out of their fuel, followed by BP ultimate.
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In regards to the burnt out valves, that would depend also on what valve seats and valves were fitted from factory. The later ones had better valve
seats. Someone will know the data. There wouldn't be many original 60's heads left that have not been repaired or replaced with hardened valve
seats
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i found that any shell fuel and i was replacing the fuel reg after 30-40 minute of run time.
i run bp 95 or 98 depending on my financial state at the time.
I run 98 in my sons bug 1904cc with higher comp, any old unmodified VW I use non E10 unleaded. Checking a 1302 & 1303 owners manual, 1300 & 1600 motors were made to run on 91 RON, higher grades wont hurt the motor, only your pocket
1200cc Formula Vees - basically stock 40hp engines - run 91 octane....not because it's cheaper, but because it gives MORE POWER !
Yeah the comp would be too low to yield the energy from higher octane fuel, thus higher octane in low comp engines reduces power.
To yield best power from 98 you need at least 7.8 ish DCR, average engine static CR that would be around 9.5-10:1
E85 can take static CR up to 18:1 of course it depends on the DCR. E85 and E100 really start to shine above 13.5:1 or 9-10:1 on high boost. And it
drops engine running temps too!
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I run a 1600 TP on Caltex 98 - works fine for me
Our 1600 TP will not run on 98 very well at all
Shell 98 v-power had a reputation for a short shelf life amongst the V8 supercar teams. Also there were reports of it fowling plugs in air cooled engines. Good reports for BP ultimate. Ethanol is no good for vw motors or most motorcycles. If I'm paying will go for 91 but few outlets have it in my area. Normally just fill a jerry can with caltex 95 when filling the work car. In a fuel injected motorcycle I am 100% certain that 98 will give a greater range than 95 or 91.Is it worth the extra cost ? Well that extra 20-30 kms might be the difference between walking or riding to the next pump. On a carburettor engine the high octane fuel is wasted if not jetted accordingly. I also give a squirt of valve saver when I remember although it isn't necessary for vw engines. Won't hurt and subaru always include upper cylinder lubricant at each service.
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Lately my engine has been making a metallic gurgling noise when it goes uphill or sometimes when I accelerate on a higher gear 3rd - 4th.
What could be the problem.
In the past I blamed it on low octane - and switched to using a higher octane and that seems to cure it. But now even using BP98 does not seem to
help?
I should also add that I have not used my Beetle in the last 5 months because I was overseas. The tank has been refilled once already - maybe its a
case of bad petrol?
Check your timing that gurgle is detonation,
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I have a China crank and Scat pulley on my sons bug, both added up to being 8 degrees retarded, if your motor has non standard parts on it do a dead stop test to find true TDC
If the noise you motor is making is like steel ball bearing in a steel tin, thats pinking or pinging depending on where your from
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same thing
the only one I've stopped using was shell. every time i used it within 15 of refilling my fuel regulator would fail and start pissing fuel out in to the engine bay.
Some historical info on octane ratings for old leaded Australian petrol. These figures come from FCAI yearbooks (up to 1987)
June 1955 - Standard was regulated to be 79 octane, while Super was 90.
August 1959 - Standard upgraded to 83. Super was upgraded to 93.
November 1962 - Standard upgraded to 85. Super was upgraded to 95.
April 1964 - Standard upgraded to 87. Super was upgraded to 97.
August 1968 - Standard upgraded to 89. Super was upgraded to 98.
August 1979 - Standard now available in both 89 and 92. Super adjusted down slightly to 97.
July 1985 - Unleaded fuel debuts with octanes 91/93.
July 1987 - Super 'premium' unleaded debuts with octane 96. Since adjusted slightly to 95. Later 'super premium' fuels added at 98.
The Australian VW1300 owners' manual from 1966 specifies 87 octane (7.3:1 compression), so today's 91 is fine for stock VWs. Don't use E10 - it
should only be used in EFI VWs made after 1986.
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