Super Unleaded

[hcanning]

Is it worth me sticking some in my MX5? Will it make a blind bit of difference to anything whatsoever?

[MX-5 Lazza]

No. It would just be a waste of money. The MX-5 ecu can't compensate for higher octane fuels.

[anonymous-user]

hcanning said:

Will it make a blind bit of difference to anything whatsoever?

Yes, your wallet will get lighter even quicker.

[hcanning]

MX-5 Lazza said:

No. It would just be a waste of money. The MX-5 ecu can't compensate for higher octane fuels.

OK ta

[Kam125]

If its an import then maybe it is worth the good fuel.

[MX-5 Lazza]

Kam125 said:

If its an import then maybe it is worth the good fuel.

Makes no difference. In fact Japan use a lower octane rating than us and the cars (UK as well as Jap spec) are tuned to use that. That's why it's safe to advance the timing to 14BTDC. If you really want to use it you can advance your timing to 16 or even 18BTDC but there is very little advantage to doing so.
The stock ecu however does not adjust the timing according to fuel octane rating in any MX-5 before the Mk3 so other than taking advantage of the improved detergents in most supers has no beneficial effects at all.

[hcanning]

What is the advantage of advancing the timing to 14BTDC? I've read baout it being done but not really much into what happens

[MX-5 Lazza]

The main advantage is more mid-range torque and better responses. Some say that it looses a small bit of power at the top end but I never noticed anything. Any loss that there might be is well made up for in gains in the mid-range which is where you really need it 99.9% of the time.
Don't expect any black/white changes though, I doubt a dyno will show more than a slight change to the torque curve but it is something you can feel.