Shell Optimax

[Guest]

I had the car Guru'd / Promaxed earlier this week and it's made a really great improvement, I've now filled up with Optimax and will continue to use it as much as possible (not very convenient I'm afraid) My question is does the 944 take a while to adjust to new fuel and if so what's actually happening?

TIA, Tim.

 

[Guest]

I dont think older cars ECUs have many parameters that can adjust to fuel, but it would take a coule of tanks to completly purge your system of the old fuel anyway. Remember you can use BP Ultimate, or any super unleaded to be honest if getting Optimax is a real problem.

 

[Diver944]

If you struggle to find a higher octane fuel one day then stay off the boost until you can.

The Guru/Promax chips are designed for the higher octane fuels and you run the risk of damage if on normal fuel. Our cars do have a knock sensor, so will alter the timing if it starts hearing pre-ignition, but for the full on boost action you should really be on Optimax and the like with those chips

 

[Guest]

That's what I was thinking, I can get it it just means going out of my way a bit. No big deal.

Tim.

 

[Fen]

I stuck Optimax in the Cab last weekend, just really for one tank to clean it up a bit as I didn't think it much cop in NA engines.

Fappin' hell was I wrong. It's much livelier now below 4,000, so it's now on tank #2 and I guess my fuel bill just went up. It does seem to go a bit further on the same amount though, but not quite enough to make up for the price premuim.

 

[richthomas]

I've always run mine on Optimax, and my lux before, mainly beacuse of the octane benefits rather than being able to actually noitce much difference, (but then I wouldn't if I've always used it[]) but I definatly wouldn't go back to regular supermarket fuel. The manual states a minimum of 95RON, so I prefer to err on the safe side and enjoy the performance and cleaning power. I think the costs would be most noticable if you are doing higher mileages and fill up often, as I don't, I like to use the good stuff[8D]

 

[Fen]

Well, I fill up at least once a wekk - more like 5 or even 6 times a month.

I never use supermarket fuel, but I've always just used Shell, Texaco or Esso unleaded in NA engines, Optimax for Turbos.

 

[NorthernBloke]

ORIGINAL: Fen

I stuck Optimax in the Cab last weekend, just really for one tank to clean it up a bit as I didn't think it much cop in NA engines.

Fappin' hell was I wrong. It's much livelier now below 4,000, so it's now on tank #2 and I guess my fuel bill just went up. It does seem to go a bit further on the same amount though, but not quite enough to make up for the price premuim.

Bolox!!

Been resisting using it in case it made a difference as I fill mine up once a week as well. As it's empty now I'll have to give it a try [X(]

Might have to stop reading things on this forum [8D]

 

[Fen]

I forget why now, but I happened to find feedback on eBay from you buying your car (the seller must have something I was interested in).

Stonking deal! You can afford Optimax...

 

[NorthernBloke]

ORIGINAL: Fen

I forget why now, but I happened to find feedback on eBay from you buying your car (the seller must have something I was interested in).

Stonking deal! You can afford Optimax...

[:-] shhhh - it was a very good deal though []

 

[Guest]

So is 'normal' unleaded not good to use in turbos? Should I be using the higher octane stuff?

 

[Fen]

Yes. Especially if you have a boost enhancer of any other sort of enhancing widgetry. If you don't, why not?

 

[Guest]

ORIGINAL: Fen

Yes. Especially if you have a boost enhancer of any other sort of enhancing widgetry. If you don't, why not?

Fen, my turbo at the moment is standard, with no enhancer or widgetry, so can I use the 'normal' stuff or not?[8|]

 

[NorthernBloke]

Right, it's now all topped up with Optimax - 50 quids worth [] @ price of petrol

 

[Guest]

I did the same today, £49.00

It definately feels much better at the low end, quite brutal in fact.

I'm so chuffed with my Guru upgrade, must get round to fitting the wastegate shims.

Tim.

 

[Fen]

ORIGINAL: matt s
Fen, my turbo at the moment is standard, with no enhancer or widgetry, so can I use the 'normal' stuff or not?[8|]

If your overboost protection never kicks in then maybe you won't get any benefit from Optimax (if it does then it will probably stop with the higher octane rating).

Although it costs £50+ for a fill you're only looking at an extra £4 over normal unleaded, so why not run the tank low and then fill it with Optimax to see if it feels different? I've run everything I've owned with a turbo on Optimax since it was launched (OK, not the diesel Slim, before you say it...)

 

[Guest]

ORIGINAL: Fen

ORIGINAL: matt s
Fen, my turbo at the moment is standard, with no enhancer or widgetry, so can I use the 'normal' stuff or not?[8|]

I've run everything I've owned with a turbo on Optimax since it was launched (OK, not the diesel Slim, before you say it...)

My hands were moving to the keyboard there till i read the last bit... Doh. []

 

[Diver944]

Matt, a standard Turbo is designed to run on normal 95 Ron unleaded and thats what I ran mine on for 20,000 miles with no problems. It's only when you start to tinker, that you can use the benefit of 98 Ron [8D]

p.s I always use Optimax now