Wow! what a smoothie! + advice on petrol?

[jureks]

Hey folks, this is my second post.
First was posted in Chat- VW related (Reassurance please) a week or so ago and I was a 'touch' concerned having visited this site and read quite a few 'bummers' re. Mk. 4 electric windows, rear wash, coils etc.
This was just after I'd bought one, but before picking up - if you get my drift.
I've now had the car (2003, Mk4 1.8t GTi, 10200m) for a couple of days  (just on local journeys so far) and have to say it's an absolute real smoothie compared to my previous
(Mk 2 1.8 8v GTi 128000m) which 'god bless it's cotton picking socks' was a  fantastic 'grunt, but go' car.
The turbo's almost too smooth on the Mk. 4 but overall the ride's fantastic.
Cockpit great, but should really have sound controls nearer or on the wheel and it's a touch difficult at present to get down to the climate controls.

Need some advice re. type of petrol.
Have read somewhere (probably here) that petrol consumption for the 1.8t gti is much worse than officially indicated and I haven't at present managed more that 32 mpg on my first 100 miles - which consisted of two runs to work  and back (about 45 miles in total ) and a little motorway driving but no serious foot down - if anything really steady  to see if I can get more out of it.  So, I'm a touch disappointed on this score.

Anybody out there using Shell's Optimax or BP's Ultimate? (I think it might be called)
and getting any real benefits?

[topher]

I always always always use optimax, and see an average of about 36/37 mpg. You may see a little more than that, because as you can see from my sig. my car isn't exactly standard  

[GaryM]

I too use only Optimax, not just for the mpg but so I can run my ignition timing a little higher.

[nrgizerbunny]

hi

this is totally my opinion but i think like gary said if you are going to use optimax you really need to get your timing adjusted accordingly.

if you use 99RON (which i think optimax is) the flash point of the fuel is much lower than 95RON (normal unleaded) so you may end up getting knocking or pinking (i can never remember which way round that is) and the engine managment will retard the ignition, thus robbing performance.


have a nice day

sanj

[gazzagtiT]

Optimax is much nicer and in some strange way, i always feel like iv done a good thing an rather proud after i'v filled up wiv optimax, would fill a lot more but i havn't got any shell's nearby, but if ur fillingwiv ur usual sain's, tesco, or whatever, if you fill up ?40 or so, i personally look to get 350miles (reset ur trip meter maybe im a bit sad but i do that all the time just out of interest) but usually only get a touch over 300!!! that peddles a bit to tempting.  

[golfvr6]

hi

this is totally my opinion but i think like gary said if you are going to use optimax you really need to get your timing adjusted accordingly.

if you use 99RON (which i think optimax is) the flash point of the fuel is much lower than 95RON (normal unleaded) so you may end up getting knocking or pinking (i can never remember which way round that is) and the engine managment will retard the ignition, thus robbing performance.


have a nice day

sanj

Since when do you get pinking from using higher octane fuel?  
I would have thought the ignition timing is non-adjustable, like most vw's after 1992  

[antgti]

I thought optimax was only 97 ron. ??

Anyway, when i've been looking at TT's i noticed that the 150bhp version is recommended to use 95 ron but the 180 and 225bhp TT are both recommended to run 97, and that is audi, same engine as 1.8t so if you have standard 150 i would say run 95 if you have a 180 or modded 150 then run 97 ron

[topher]

Since when do you get pinking from using higher octane fuel?  
I would have thought the ignition timing is non-adjustable, like most vw's after 1992  

Timing and boost is adjustable on the later (DBW) 1.8T's through Revo's SPS3 (serial port switch). They look like a handy piece of kit, shame I'm stuck with the SPS1, all i can do is switch between stock/performance modes  

[jureks]

thanks for all the views, folks - doesn't seem to be much in it overall and can't be 'asked'  (nor have a clue actually) how to  tune the ignition so will probably stick to the old 95 ron. for now and hope for the best +save a few bob! too.

Just for info. have just returned from a run down to Heathrow and back  (approx. 180 mls, predominately motorway) and managed a reasonably healthy 36.4 which ain't bad really.

It really is a smoothie, this 1.8t,  isn't it?

na zdrowie.



 

[nrgizerbunny]

if you use higher octane fuel the flash point is lower, the fuel goes bang and you get a shock wave on the top of the piston which i believe is called pinking (but iget confused between pinking and knocking).

have a nice day

sanj