The differences between fuels.

In a copy of Banzia i have just bought there is an interesting read that should quash most oppinions on tesco's 99 ron fuel out performing Shell's optimax and BP's ultimate.


I will bring home the mag tomorrow and post the graphs that they have produced.

Basicly, they took 4 fuels, normal SM 95 ron, Shells optimax, BP's ultimate and Tesco's 99 ron fuels and tested them in an engine on a dyno. its quite an interesting read, so i would recomand buying it.

Results to follow tomorrow if someone hasnt already post them by the time i get in tomorrow.


John

 

John look forward to reading the results


Hower how it was mapped would play a biggest part in any variance. if Mapped to 95-98 ron (eg Subaru WRXUK and Subaru STiUK) 98 ron (eg with PPP) or 100ron (STiJDM) IMHO

Bigger power outputs from the greater ron Fuel has never been my intension or need. As lower ron Fuels on high performance Cars is a 5 horse power more on 300+ then "running hot/detting" and melted engines

Tony

 

not quoting exact figures, but, the engine used was a turbo'd cosworth unit, which was previously dynoed at 500bhp approx.

The were playing with the timing i think, now i dont know a great deal about this area, but it was started at 13 degrees and they were trying to see how far they could advance it if any.

Now from memory, the 95 ron made 518bhp, tescos was 530, ultimate was 540 and optimax was 548.

There was a torque figure given as well but off hand i cant remember. Dont really want to say to much as im not sure of all the data supplied and dont really want to give a half arsed version of the write up like i just have lol


For those that have not read it in the mag, i will post it up tomorrow when i get a chance


John

 

John,
Thanks i'll try and find a copy and have a read but sounds like a proper test

Tony

 

I dont see the point in doing things like this, it may show which fuel offers greater potential for bhp, but fuel is so inconsistent even within the same grade that its pointless. I haven't read the article but it sounds as though they have mapped it to within an inch of its life on each of the fuels used, and you cant do this in real world scenarios due to the aforementioned inconsistencies.

 

To be honest i don't really care what tests say.....it is how each fuel feels in MY car that i am bothered about.

Personally i only use Tesco 99 or Optimax, runs crap on BP.
But i know others say different, and others agree.

Just choose which feels best in your car and stick to that, ignore what magazine tests say.

 

Right the TEST

The test was carried out on a COSWORTH YB engine running 8 green injectors and a roller-bearing T4 turbo at FIELD MOTORSPORTS. The engine was set to run at a constand 6500rpm and 2.0 bar of boost with a ignition value of 13 degrees advance.


Fuels used

supermarket 95 RON
Tescos 99 RON
BP Ultimate 97 RON
Shell Optimax 98 RON

RESULTS

supermarket 95 RON

They could not get the engine to run safely on the 13 deg advance, so it had to be set back @10.75 deg to record a safe power run

At peak power they recorded 516bhp and 417ft/lb torque



Tescos 99 RON

@ 13 deg, a peek power of 521bhp and 421 ft/lb torque was recorded. They could avance it only by 0.75 deg to get a final output of 523bhp and 423 ft/lb torque



BP Ultimate 97 RON

@ 13 deg, a peek power of 530bhp and 428 ft/lb torque was recorded. They could avance by 2.0 deg to get a final output of 537bhp and 434 ft/lb torque



Shell Optimax 98 RON

@ 13 deg, a peek power of 537bhp and 434 ft/lb torque was recorded. They could avance by 3.0 deg to get a final output of 547bhp and 442ft/lb torque



So, there are two sets of figures there to take in. Question is, what is the ignition advance usualy set to on a standard uk impreza??? Im pretty far from an expert on this, but it does look to me that as in terms of the safe running of your engine, BP and optimax are the safer option for cars set at the 13deg marks.


This was just something i found quite an interesting read, the article goes into more detail. Maybe someone with more knowlage than myself can add to this or in fact prove that this test was just a waste of time.



John

 

I always personally rated Optimax as the best fuel available - even after Tesco 99 appear on the scene. Nice to see this backing that up.

 

CAnt comment on Tesco's 99 RON, i mean i only live in the ******* middle of the UK, i cant expect Tesco to actually supply my stores with it ffs!
stnuc!