Advantage of 95 ULP at altitude

[Skwinty]

That makes sense, since your car has a forced-induction engine...

True, but if you look at the database link I posted, you will see a significant number of 3 series BMW's have 93 octane as the recommended fuel.

The rest of the 3 series have 95 octane as the recommended.

So, if you want the optimal for your car you would use the recommended fuel. :thumbs:

 

[Pr0PheT]

I think the problem is that with the general ethical standards of most organisations and people in South Africa most pump stations are probably selling 93 as 95 so even if there is a scientfic difference under normal conditions you wont actually notice anything unless you try the same test at several different filling stations. All I know is that if you drive diesel use 50ppm and not 500ppm.

 

[rick540]

I think the problem is that with the general ethical standards of most organisations and people in South Africa most pump stations are probably selling 93 as 95 so even if there is a scientfic difference under normal conditions you wont actually notice anything unless you try the same test at several different filling stations. All I know is that if you drive diesel use 50ppm and not 500ppm.

Once again, Sulphur is a very good lubricant, it's used in EP gear oil as an additive. If you have an older diesel, don't waste your cash as it may never have been designed for 50ppm and wear could increase.

I think Swinty summed it up 100% u_s_e t_h_e r_e_c_c_o_m_e_n_d_e_d fuel grade. if the owners manual says use this or that, they actually mean use this or that for some very good reasons.