hi guys

simple i know but can i run my sti v5 on tesco 99 octane as i have to go out of my way now to fill up at shell. i have used shell v power for the last three years but now not having a shell garage near me i have to drive out my way, when i have tesco round the corner.

will using tesco be ok as always keep hearing about horror stories using BP etc.

cheers

 

Tesco 99 was fine in the spec'C' for 3 years.

 

I've used Tesco 99 since it's release for the same reason you state above. My nearest shell garage is 20mins away.

As long as your car wasn't mapped for the V-power it should be fine. If it was mapped, then a simple tweak should do the trick.

 

That doesn't mean a lot in the context of this thread. The newage ECUs are far more proactive to variations in fuel quality than the classic ones.

Tesco is better than BP but we simply can't tell you with certainty whether your car will be okay, and anyone doing so here is taking a guess with your engine. They may well be right but I doubt they'll be willing to cough for the consequences if their guess turns out to be wrong.

If it's still running the ex-factory management then it is already running lower octane fuel than it is mapped for, even on V-Power. Margins tighten further if the airflow meter, an injector, fuel pressure reg or pump on your 10 year old car is anything other than 100%.

If you want to be sure whether your car is running within safe limits, relying on guesses from people on an internet forum who've never seen it, let alone driven it, is not the way to go. Fitting some knock monitoring kit, for example, will give you some first hand answers.

 

tesco 99 gives almost identical detination characteristics to Shell Optimax Dunc told me.. so about as safe as it gets without additives or using E85

 

I run my mapped JDM 2005 STI on both Tesco 99 and Shell Optimax or what ever its called now.

I don't have issues with either and they are only two that I will put in my car.

 

Fitting some knock monitoring kit, for example, will give you some first hand answers

i have a knock sensor fitted to the car and is running standed ecu.

i know its had normal unleaded in it as filled up by the garage i got it from but vpower ever since.

is it worth sticking 20 quid in and seeing what happens or stick to v power

 

Our local Tesco only seems to get supplies irregularly, and when it does, they are gone in days.

When I get my car back, and have it's map redone after running in, I think I'll ask for it to be mapped on 95 RON. I'm sick of being raped for V-Power and with a few BHP to play with, I don't think I'll miss it.

 

Oh I think you will

Driving last summer on those hot days... murder... imagine that every day of the week and ever week of the year... no ta... I'll pay an extra £5 a fill up for the sheer factor..

 

my V4 wrx sti was mapped on V-Power.

I however choose to use tesco as it is only round the corner where as shell is about a 20 min drive.

However when I go on long motorway runs I tend to use v-power.
Havent really noticed any difference power wise and I have both lambda link and knock and avcr and never seen either flash away out of the ordinary. infact the Knock never lights up except the bottom one which means its on I think

 

remap if change from 99octane vpower to 99octane tesco? hmmmmmkay. Mine was mapped for vpower but i have used tesco99 for almost 3 years. ('07 wrx)

 

Both work almost identically in terms of the amount of timing, boost etc that can be run.

I have noticed that Tesco 99 goes off quicker though - probably something to do with the lower grade base fuel which has then been upped octane wise with e85. It also runs marginally leaner on Tesco 99.

It shouldn't make a difference but I would at least get a knock monitor on there to see first hand on your unmapped car.

As an aside people always ask whether the fuel makes a difference.. I mapped a car late 2008 and it was dyno'd last feb at 326bhp (blob wrx with vf35 and sti tmic) on vpower. Same car on saturday made 300.1bhp on the same rollers and no other changes running on sainsburys 97 because the owner didnt think it would make a difference (despite my advise to the contrary). You can see the exact point in the dyno run where the ecu heard det and the affect on the power was huge.

You notice 26bhp.

 

i got my car from jap import garage they told me to use tesco 99,my son got clio 182 he was allways usin shell v power but changed to tesco 99

 

I agree with mneame with regards to what you have mapped it on especially with newer models.

A lot of these high octane fuels though, come out of the same tanks.... and they just go out to different stations

 

Interesting thread, I have the same problem as V Power has run run dry by me at the moment, looks like Tesco 99 for the short term.

 

V power plus an octane booster till my version 6 gets mapped..........

 

I have always used Tesco 99 on my 8 skylines 3 supras 4 classics and 2 newage and never had any probs mate. I am more than sure you will be fine...