What Fuel Octane?

[thomasrally 3]

What fuel octane is most suitable for a 1600 rally car XU engine with 10.5:1 compression?

 

I can get my hands on both tesco super unleaded and optmax or equivilent around here but which would be best suited?

[Chris H 10]

What fuel octane is most suitable for a 1600 rally car XU engine with 10.5:1 compression?

 

I can get my hands on both tesco super unleaded and optmax or equivilent around here but which would be best suited?

 

I've run my car on both with no noticable difference. I'd go for which ever is likely to have the quickest turnover on fuel...the fresher the batch the better.

 

Are you going to fully map the car on one of them...if not them i wouldn't worry too much as you can't optimise the map for one of them...and to be honnest the pump fuel probably isn't consisitent enough to be able to map the car to its extreme.

[mr_exe 1]

I've found that tesco 99 makes our Mi16 tickover horribly, so if you are going of a higher octane fuel i'd recommend Optimax based on my own findings

[Guest Kidmans]

V-Power (replaced Optimax) over Tesco 99. Engine on mine seems to run smoother on the Shell.

[Retro Pug 0 1 Cars]

Another vote for V-Power my GTI6 seems to run much smoother.

[CaptainK 11]

My 205 GTi6 with throttle bodies and aftermarket management has been mapped to Shell V-Power, so I better use it.