23 replies to this topic

[chrisvx220]

Hoping to pick up my first VX this week and just wondered what everyone fills theirs up with normal unleaded or the high octane stuff? Is there a noticable difference?

[Zoobeef]

Hoping to pick up my first VX this week and just wondered what everyone fills theirs up with normal unleaded or the high octane stuff? Is there a noticable difference?

You can fill it up on either but as mines a weekend toy and i dont do many miles i dont mind filling up on v-power. Cant say ive noticed a difference but not really looked. Cliffe was doing some tests in his on both so he might be along soon to comment

[VIX]

Standard NA, I used mainly regular with the occasional treat of V-Power. If you're getting a Turbo then I've no idea so check the handbook. Take it easy.

Edited by VIX, 16 May 2010 - 03:54 PM.

[vaux2008]

Welcome. Dont think there is much difference at all to be honest unless you are at max revs all the time. If its at the pump I may use it but i have used both and havent realy noticed anything on the VX but my racing Nova that revs to about 8000rpm, I can notice between the different fuels near the top of the rev range.

[snoopstah]

Standard turbo is I believe fine with 95RON. If you have a remapped turbo (especially above stage 2) then it'll have been mapped for at least 97RON (mine is mapped for 98RON) so while it'll work on 95 in an emergency, you shouldn't drive it hard as you'll risk detonation. The 2.2 engine was used in repmobiles, so as standard they'll run quite happily on pretty much anything . I suspect as it's used in American cars as well it'll quite happily run on their 87-octane standard fuel too (equivalent to around 92RON in the UK). I believe both ECUs have the ability to adjust to different octanes, but that they are generally better at adjusting to lower-than-expected fuel rather than higher-than-expected fuel. Either way it'll take a few hundred miles for the ECU to adapt and you to notice any difference what-so-ever -- anyone who fills up with super-unleaded and then claims an immediate improvement is kidding themselves unless the old fuel was contaminated.

Edited by snoopstah, 16 May 2010 - 04:01 PM.

[Pooh Bear]

anyone who fills up with super-unleaded and then claims an immediate improvement is kidding themselves unless the old fuel was contaminated.

Don't agree.
I use 99 in the vx (again it is mapped for it so pretty obvious I need to use it) but I also switched to this fuel for my everyday shed omega and it DOES make a difference. Better fuel economy and running performance.

Edited by Penny, 16 May 2010 - 04:43 PM.

[snoopstah]

anyone who fills up with super-unleaded and then claims an immediate improvement is kidding themselves unless the old fuel was contaminated.

Don't agree.
I use 99 in the vx (again it is mapped for it so pretty obvious I need to use it) but I also switched to this fuel for my everyday shed omega and it DOES make a difference. Better fuel economy and running performance.

Well you wouldn't -- as I said, you were kidding yourself. As soon as you think it's better then you won't easily be convinced it's not

But seriously, my comment was specific to the VX -- I have no idea about the Omega. My limited understanding is that if it has carbs then any possible advantage will be instantaneous, so that might be the case. You still need to fundamentally adjust the timing to see any significant advantage though, which is a manual process on a carbed car, and I'd be very surprised if any ECU would step up the timing instantaneously except for race ECUs.

[slindborg]

my 3.0 v6 omega ran thirsty no matter what fuel you gave it fuel is fcuking fuel for everyday driving... snoop has covered it pretty well in that unless you have had the ecu fiddled with then it will cope with whatever you can give it in the UK

[snoopstah]

snoop has covered it pretty well

First time for everything! Typical that I finally get something vaguely right just when I'm selling up

[Bobby]

V-Power! Don't know if there is a difference, never tried the regular stuff. Works out £2-ish more a tank, I'm happy to pay that for a placebo effect

[Pooh Bear]

Well you wouldn't -- as I said, you were kidding yourself. As soon as you think it's better then you won't easily be convinced it's not

But seriously, my comment was specific to the VX -- I have no idea about the Omega. My limited understanding is that if it has carbs then any possible advantage will be instantaneous, so that might be the case. You still need to fundamentally adjust the timing to see any significant advantage though, which is a manual process on a carbed car, and I'd be very surprised if any ECU would step up the timing instantaneously except for race ECUs.

My omega doesn't have carbs

I'm no fool and neither is my other half (who is a technician) so in our experience:

We have used 99 in a previous Z22SE engined Vaux and noticed better fuel economy and running.
I use the 99 in my omega and also noticed the above.

Believe me, at the price fuel is today I would love to use ordinary 95 in my everyday car but it I get a noticible sluggish performance and poor fuel return.

I'm not gonna argue whith you on something I've tried and tested and you haven't

[snoopstah]

I'm not gonna argue whith you on something I've tried and tested and you haven't

Absolutely, it's your car and if you're happy with it then that's the only thing that matters.

I was merely pointing out that there is a significant psychological effect involved in performance increases, and without a double-blind test the word of one person shouldn't be taken as gospel. Just look at the number of people on this forum and most other car forums who are totally convinced that upgrading the brakes makes their car stop 'so much quicker'.

Using super unleaded on a car that may not need it is an expensive choice to make these days, and I just wanted to make sure that people make up their own minds based on their own situation

[Pooh Bear]

....and without a double-blind test the word of one person shouldn't be taken as gospel.

Using super unleaded on a car that may not need it is an expensive choice to make these days, and I just wanted to make sure that people make up their own minds based on their own situation

Couldn't agree more

[yaaan]

Not long after I got mine I was browsing the Thorney website and on there they claimed to have tested the hogher octane stuff and reckoned it gave an improvement so I thought I would give it a try. I ran it for a few tank fulls and to be honest I didn't notice much difference. It may possibly have been a little quicker off te mark but not enough to outweight the downside....the 20% increase in fuel comsumption! Normal unleaded I can get about 200 miles to a tank full but with the 98RON I was lucky to see 160. Being that much more expensive and having to fill up that much more often, I reckon I'll be better off waiting a bit and spending the money I save on a decent mod

[slindborg]

Not long after I got mine I was browsing the Thorney website and on there they claimed to have tested the hogher octane stuff and reckoned it gave an improvement so I thought I would give it a try. I ran it for a few tank fulls and to be honest I didn't notice much difference. It may possibly have been a little quicker off te mark but not enough to outweight the downside....the 20% increase in fuel comsumption! Normal unleaded I can get about 200 miles to a tank full but with the 98RON I was lucky to see 160. Being that much more expensive and having to fill up that much more often, I reckon I'll be better off waiting a bit and spending the money I save on a decent mod

note the fuel test they did was with a fuel that sponsors them..... amazing that it 'won'



I'd sooner see higher calorific value fuel at the pump than higher octane... far more useful

[Zoobeef]

As i said at the top cliffe was testing different fuels for there comsumption rates so would be interesting to see if he got any answers

[yaaan]

note the fuel test they did was with a fuel that sponsors them..... amazing that it 'won'

Curious that

I'll be sticking with the regular stuff. Any loss in preformance is worth it if I get a greater range than my motorbike!

[Bobby]

....the 20% increase in fuel comsumption! Normal unleaded I can get about 200 miles to a tank full but with the 98RON I was lucky to see 160.

Strange that. I'm getting 220 miles to a tank consistently on V-Power. Not particularly trying to be economical.

Possible performance benefits aside, I vaguely recall reading an article (which seemed credible enough) about how v-power kept the innards of the engine cleaner than run of the mill fuel.

[slindborg]

oddly (well not really), both our cars run like a sack of turn on Shell fuel (boggo or super spunky headgasket killer Optimax V-Flower)

The only time I have noticed a good kick up the ass from fuel is when I had a 1.2 nova and put real honest 4Star in there

[G-Bob]

The only time I have noticed a good kick up the ass from fuel is when I had a 1.2 nova and put real honest 4Star in there

....and I bet that was after you smoked out the entire street by pouring redex into the carbs!?!?!?!