99ron in mk1 Gti?

Hi people!
For years now I've been religiously filling my Leon CupraR with 99ron stuff as it really does make a difference, plus the maps set up to run on it.
I've been giving my mk 1 the same treatment for the last few months (after her 5 year sleep) and was wondering if a small 1.8 8v would benefit at all or am I wasting my money? Would she run better on the normal stuff as she's an old bird??
Anyone got an opinion?
Thanks and good afternoon

I am guessing the seat has a turbo?

Waste of money in a non-turbo car unless its been tuned only to use 99 octane, then that's a big issue if you can't get it.

I run mine on super unleaded as it runs better, with normal unleaded it may pink under load, it does lose about 5bhp on normal unleaded but its just personal pref

chris

99RON is different to super unleaded though. Super is 97RON.

I suppose it'll come down to economy in the end, I know company's claim better mpg and engine life, but will it make up for the extra 7p per litre??

99 RON - I wouldn't bother, just stick to super as VW recommended

In actual fact VW recommended 98 RON :-) in the DX GTI engine

lhasadreams said

In actual fact VW recommended 98 RON :-) in the DX GTI engine

Actually yes you are right 98RON for both the DX and EG lumps…

mine was happy on super and optimax, gave better mpg, though maybe wasn't worth the cost? but reduced pinking under load when using it.


Use if feeling flush?

So if you put an Audi or Mk2 16V WUR with the larger throttle body on (larger second butterfly) and perform the "WUR mod" you could squeeze a few more bhp out of the engine when running 99 RON. But once setup like this you will always have to stick to 99 RON to avoid potential pinking.
These WUR's allow you to alter the control pressure - best setup with a wideband lambda sensor though to ensure that it does not run lean higher up the rev range.
You might be able to dial in a little more advance as well, but this is best checked on a rolling road as advance for advance sake without an increase in torque just makes the engine run hotter for no gain.

I had a k-star on mine a few years back and had it initially setup to stop pinking on 95 RON fuel - but when it was no longer my everyday car I had it remapped to give more power on 97 RON. 99 RON is not available much around where i live.

paul_c said

99RON is different to super unleaded though. Super is 97RON.

very true paul it is, no dispute there but i never said it was 99ron in the first place, just saying my findings buddy

chris  

So 98ron sounds about perfect then?

yes mate, perfectly fine, mine runs bang on all day no worries

chris