octane plug

[reid_em]

hello everyone i just been talking to me neighbourgh and he metioned my octane sensor. he said they all have numbers on them (mine is 91 at current) i have a 1.6 gsi engine tuned with cams bigger pistons ect. is this something i could change to increase power if so which number would anyone reccomened. i hope this makes sence hope to hear back from you all soon
reid

[Pistol Pete]

Wouldnt have thought changing it will do much TBH. Might make it run better if octane is increased. Or it could make it run like a bag of spanners....

[CoolTiger]

if you turn it round it should say 95 that might help a little i have no idea but i think it would other wise why have it :D also its called a ron plug

[dazzabhoy]

not much point changing it unless you are running higher octane fuel no point setting it to 95 if your using 91

[Nova_Tek]

I never knew you could get 91RON at the pumps?

If you are using Premium unleaded i.e 95 ocatane set it to 95. That way you make the most of the fuel as it advances / retards the ignition to suit the fuel type.

Its not gonna give you 36547812471 BHP increase but its there for a reason.

My dads 8v SEH Cav has one which is 95 & 98 but his temporary run around the 20NE had a 95 & 91 plug.

[dazzabhoy]

I never knew you could get 91RON at the pumps?

If you are using Premium unleaded i.e 95 ocatane set it to 95. That way you make the most of the fuel as it advances / retards the ignition to suit the fuel type.

Its not gonna give you 36547812471 BHP increase but its there for a reason.

My dads 8v SEH Cav has one which is 95 & 98 but his temporary run around the 20NE had a 95 & 91 plug.

i dont know if you can it was in the original post that it was at 91 already i was just using it as an example similar to yours

[Rich]

If you turn it around it will have 95, which is what you want to be running.

If you use optimax, v-power etc that is 98 octane rating. You can get 95/98 plug and run the 98 side. Not gonna make a huge difference but its designed to run with the different fuels.

[novaguy08]

91 ron is 4-star i thinks.
im trying to get hold of a 95/98 one so that i can put some v-power in there and get the benefits from it.

[Guderian]

yeah i have done this mod on a 1.2 spi. On this particular system the 91 setting is zero ohms, and the 95 setting is 220 ohms. The octane plug is fed with a reference voltage of 5 which is 'stepped down' by the resistance in the octane plug. If you plug is Black (91/95) then you need a Brown one (95/98) from a breakers. On the 98 setting this has a resistance of 470 ohms which advances the ignition by 5 degrees and remaps the injection.

on my vehicle it makes a--- very small-- difference above 3000rpm approx.

My MPG unaffected at 48!!

Once on the 98 setting do not feed it on 95 premium unleaded as it will detonate and you may not be able to hear it doing so.

NB 91 is pool petrol (not applicable to UK) 95 is premium unleaded (what everybody tends to use) and 98 is super unleaded. super varies however according to supplier. May be anywhere between 97-99. Eco gits don't like it because of the high level of aromatics.

[Guderian]

Oh and be careful selecting octane plugs, as different vauxhall FI systems use different resistances hence a yellow 95/98 plug will be harmful to a car meant to be using a brown 95/98 plug.

A source of brown 95/98 plug/s is certain Mk 3 Cavs. But in reality if the supply dries up all you need is a resistor of the appropriate value from Maplins or similar.

see topbuzz w/site.

[novaguy08]

read up on there, trip to the breakers yard tomorrow me thinks!!

[Guderian]

....A small mod, but for a couple of quid (and an extra penny a mile in fuel) was good for a laugh.

With the comedy 4spd gearbox (in 4th) i got a consistent improvement of 0.6 sec in the 40-60 time. There was no improvement in 30-50.

[novaguy08]

oooo nearly a sec improvement....... sod it im going there now dont care if they closed lol

[novaguy08]

right question, just got a new brown RON plug to go into my Car, read topbuzz & the 95 side is the same resistance as the Black one currently on there, but the 98 side, is the ECU going to recognize it?

[Guderian]

Yes. The 95 side WILL be the same as the old one. You now simply have the choice of the 98 setting, the ECU will read the 470 ohms and modify the settings to suit.

The holder on the car has a small black arrow moulded into it; hard to see but if this points to the 98 on the plug this is now correct for Super unleaded. I trust you have a tankful of super already!

Just don't expect to set the tyres alight..!

[novaguy08]

Yeah i read the topbuzz website, the brown 95 is the same as the black 95 (which is why i got it :D) I have 34 or so liters of super in there on top of about 8 or so of reg and a lil bit of redex, had a lil test on the way home and its a lil bit better :D bit again im not expecting to set the road on fire!