octane/RON plugs....what are they?

[Stanley]

My Corsa SRi (C14SE) has one and i dont know what it does/is

Someone please enlighten me ...

Phanx!!

[novacabrio]

Its for the use of high octane fuel, your ment to turn it around I belive

[Asa-James]

as stated above, one way is 95 RON and the other is 98 RON (i think) just turn it upside down when you put your super fuel in you tank

[Adam]

You might find one side is 91 and the other is 95.
Most are.

It changes the ignition map the ecu runs, based on the fuel octane(Ron)

[Stanley]

So if i was to fill up with Optimax but keep the RON plug on 95 RON, what would happen?

And vice-versa?

[Adam]

Optimax with 95Ron plug would do naff all in terms of any performance change.

But if you filled up with Std unleaded(95ron) and had a 98Ron plug fitted the engine would be pinking(due to running a map not suitable for a lower octane fuel)

[chimp007_uk]

whats this about? i've never ever heard or this!?! anyonw got pics of it? and where is it situated?

[Spudly]

Does that mean on an SPi with a plug that only has 95 on it wont be able to usse a 08 plug if i were to fit one and run optimax or similar in it then?
I know it wont make much (if any) difference but would it be worth trying?

[Adam]

I dont think you can just simply swap the plug.
As if originally it came with a 91/95 plug i dont think the Ecu is mapped for a 98ron plug.

Yes SPI's do have one. Its situated on the bulkhead near the wiper motor.

[Jack]

On a N/A car, especially one of small CC, you'd be better off saving your money than spending it on VPower. Even if you did manage to tune the ECU to take account of the higher RON.

Bearing in mind higher RON = less calorific energy in the fuel :p

[staggy_gsi]

I dont think you can just simply swap the plug.

you can swap them but it doesnt really make alot of difference

[bump]

occational fils of higher RON fuel can have the added benifit of decoking the head due to increased detonation temp.

[Adam]

you can swap them but it doesnt really make alot of difference
Yeah you can physically swap them straight over, but i wasn't sure if the ecu would be able to use the new plug if it was mapped for a 91/95 plug.

But as there just a resistor perhaps it would work.

[Stuart]

as jack said, NO point in using anything other than bog std 95ron fuel in anything N/A untuned or older than about 1995 (vauxhalls that is) as there simply isnt the automatic adjustment available, plus high octane fuels werent common place before 1995 either so companies wouldnt ahve put in maps to use them that well either.

leave it on 95 and be done with it.

[Jack]

But as there just a resistor perhaps it would work.
Oooh, I see a possible ebay marketing opportunity here lol

[Riggy]

lol gte/gsi nova's came with a 95/98 ron octane plug so they do have the map for 98 ron

as ad said the different colours are just different amounts of resistance ,

by changing the ron plug it changes the ignition timing by a slight amount , but i did find that pepe would throw loads of ecu lights up on the std brown 98 ron plug but when i fitted a yellow 98 from a mk3 astra it stoped the prob and ran smothly :thumb:

[Adam]

I just stick with my 95ron jobbie, seeing as i've never bought any "super" unleaded in my life lol