Would I be better off with Premium Fuel

someguy · Post by **someguy** » Sat Feb 13, 2010 5:31 pm

Hi All.

Over the last few weeks I have noticed my EA82 has started to ping while sitting in 4th.

It also seems to have lost alot of its power.

I have also been getting around 13-14l/100km which seems a bit high for an engine that small (i don't drive it hard either)

Now I have been told that this is due to crappy batches of regular unleaded that lots of aussie servos have been getting.

I have also been told that by filling up with premium it should help with the pinging/power and should also help me get a bit better fuel consumption (I was told by a mate who also has an EA82 I should be averaging around 10l/100km.

Can anyone confim this before I go and spend more on fuel?

Thanks

PS I am also thinking of getting some upper engine cleaner to flush the engine out as I don't think the previous owner would have ever done that. does anyone know where the best place in adelaide would be to pick some up?

Gannon · Post by **Gannon** » Sat Feb 13, 2010 9:39 pm

Premium unleaded will stop your pinging, but wont gain you any power directly.

The idea of getting more power from premium is because you can advance your timing to take advantage of the increased knock resistance. This is what gives you more power

You can get the upper engine cleaner from any Subaru dealer.

twilightprotege · Post by **twilightprotege** » Sat Feb 13, 2010 9:55 pm

what about E10? has octane between regular and premium, and cheapest of all!

maxxair · Post by **maxxair** » Sat Feb 13, 2010 11:27 pm

run premium. and see ebay for a deal on UEC.

someguy · Post by **someguy** » Sat Feb 13, 2010 11:42 pm

Thanks for the info guys.

Im not so concerned about the performance.

More the economy, I have heard mixed reports....some say I will get better economy with premium some say I won't

I don't really want to pay 10c per litre extra if im not going to get any gain from it

someguy · Post by **someguy** » Sat Feb 13, 2010 11:43 pm

twilightprotege wrote:what about E10? has octane between regular and premium, and cheapest of all!

Its cheaper because it burns faster.

That will just make my economy even worse

And I have heard mixed reports on how healthy it is for your engine

stephendean · Post by **stephendean** » Sun Feb 14, 2010 1:58 am

I use premium and I have found that the economy improved a lot compared to normal unleaded. So the extra cost was not a problem I basicly got the money back in the extra mileage

twilightprotege · Post by **twilightprotege** » Sun Feb 14, 2010 5:59 am

E10 doesnt burn faster (so to speak), you just need a little bit more fuel to burn at the same a/f ratio. 100% ethanol for example you need something like 4 times the amount of fuel to get a safe a/f ratio.

however 10% is pretty small. the reports on it being bad for your engine is rubbish. it's cleansing!

i still think E10 is the best value for money.

Gannon · Post by **Gannon** » Sun Feb 14, 2010 7:40 am

The only cars that get an increase in economy with premium fuel are those that run closed loop ignition timing (i.e. have a knock sensor)

Or if you manually advance your timing of your distributor to take advantage of the increased knock resistance.

Not all E10 fuels have a higher octane rating.

Yes ethanol increases the octane rating but some servos use 87 octane petrol and boost it to 91 with the ethanol.

Others use 91 and boost it to 95 with the ethanol

One servo i used to go to had

twilightprotege · Post by **twilightprotege** » Sun Feb 14, 2010 8:00 am

yes true - you have to watch for that. shell uses 91ron and adds 10% eth, thus making it about 94-95ron. i think bp uses e10 to get their ron up to 91. bit dodgy imo.

Gannon · Post by **Gannon** » Sun Feb 14, 2010 8:58 am

For ages i ran my EA82T on the E10 95 because it was 12c cheaper than regular 95. But then they changed from Shell to United and the E10 became 91, but the price stayed the same.

steptoe · Post by **steptoe** » Sun Feb 14, 2010 9:00 am

the quiet achiever and shell used to be same fuel source

thought e10 not good for metal tanks

check state of tune first, compresion, plug conditin and gap, timing

an old school upper cylinder cleanout was to slowly pour brake fluid into carby with fast idle to revving bejesus out of it as you pour, said to decarbon things and make a lot of toxic white smoke !

YouTube · Post by **El_Freddo** » Sun Feb 14, 2010 9:15 pm

Someguy, How many K's has this EA82 seen? I'd be looking at cleaning out the carbie, then tuning it. Make sure your plugs and leads are in good condition and the air cleaner is clean - if you don't know/can't remember when it was last replaced, replace it.

My old EA82 got 400km to 50+ litres. Performance sucked too - but that was partly due to the age of the motor and its unknown condition. I ended up with another later model carb and manifold on it and got some improvement in performance and economy. There must have been something wrong with the anti pollution gear on the old manifold that I didn't pick up/couldn't care about.

Check your vacuum lines too. Any cracks/holes or loose hoses will drop your performance and you'll use more fuel too.

stephendean wrote:I use premium and I have found that the economy improved a lot compared to normal unleaded. So the extra cost was not a problem I basicly got the money back in the extra mileage

Fair enough - but are we talking about a carbie EA82'd L series? Or a later model subi? Later model subi's will do this due to the knock sensor and the ECU advancing timing/adjusting running perametres as Suparoo has said.

Cheers

Bennie

AlpineRaven · Post by **AlpineRaven** » Sun Feb 14, 2010 9:22 pm

again it depends on the environment and how you drive your subaru...
I also find prem fuel better than unleaded in my liberty..
Cheers
AP

someguy · Post by **someguy** » Mon Feb 15, 2010 8:10 am

El_Freddo wrote:Someguy, How many K's has this EA82 seen? I'd be looking at cleaning out the carbie, then tuning it. Make sure your plugs and leads are in good condition and the air cleaner is clean - if you don't know/can't remember when it was last replaced, replace it.

My old EA82 got 400km to 50+ litres. Performance sucked too - but that was partly due to the age of the motor and its unknown condition. I ended up with another later model carb and manifold on it and got some improvement in performance and economy. There must have been something wrong with the anti pollution gear on the old manifold that I didn't pick up/couldn't care about.

Check your vacuum lines too. Any cracks/holes or loose hoses will drop your performance and you'll use more fuel too.

Fair enough - but are we talking about a carbie EA82'd L series? Or a later model subi? Later model subi's will do this due to the knock sensor and the ECU advancing timing/adjusting running perametres as Suparoo has said.

Cheers

Bennie

The car itself has done 360,000 but the engine was rebuilt (done 120,000 since), Air filter is new, Plugs are around 7-8k old, god knows how old the leads are though so will replace them, most hoses look good.

The carbie was rebuilt by a specialist around 60,000km ago.

Like I said before I might run some upper engine cleaner through it and see how I go.

steptoe · Post by **steptoe** » Mon Feb 15, 2010 8:38 am

When I ran 98 in my EA81 quadthrottle quadrazontal ( that's what Subaru called it in 70's) i did feel a torquier motor in the lower rev range (with foot to floor) but never sampled better mileage due to only buying ten bucks at a time on a near dry tank then fill with normal catspiss. That's how I got my thrill until I went EA82T

T'subaru · Post by **T'subaru** » Mon Feb 15, 2010 9:20 am

I cant say ive noticed a difference between unled and premium in my sub as much as ive noticed changes in run conditions when using the cheepie stuff. I stick with chevron or shell thinking Im getting a better quality fuel. Its bounced around abit but avg 2.99 us per gal / 2.71 per gal cheepie for unled.

maxxair · Post by **maxxair** » Mon Feb 15, 2010 11:52 am

i used to go with e10, but when illd put premium in aftre that its went noticable harder, especially overtaking. but premium was like 3 cents more, then 6 now 9+cents more. ripoff merchants. so i run unleaded. stuff e10, for the 3 (sometimes 2) cent saving car goes crap and i think personally wears out quicker. brumby EJ22 will get nothing but the best though.

Gannon · Post by **Gannon** » Mon Feb 15, 2010 4:32 pm

I heard there was talk of making all fuel a minimum 100 RON so car manufacturers can tune their engines for more power and efficiency.

YouTube · Post by **El_Freddo** » Mon Feb 15, 2010 8:58 pm

Suparoo wrote:I heard there was talk of making all fuel a minimum 100 RON so car manufacturers can tune their engines for more power and efficiency.

Interesting - I wonder how much that would cost us... Why not just use good ol' Avgas - 130 RON last time I looked (about 10 or 12 years ago now)... I remember one of the local guys who was seriously into his Rallying pulling up at the local airfield to fill up - at 69.9 cpl while we were paying 78 cpl at the pump (fuel prices had started to move upward and the airfield hadn't filled up their tank since then, thus the cheaper price).

Cheers

Bennie