Engine detonation?, Using different fuel types with a turbo Options

[Illyont]

Hey guys!

I see that the question of fuel comes up in quite a lot of the topics about turboing the Celica. If you are running on 91 or 93 octane (you really run on that in US?) you are in for a real blowout if running above 10 psi or something? Or is the 93 safe?

Anyway, we have 95 and 98 octane in Norway (regular gas) and my Celica is using 95 (factory default). Would that mean that I don't have to worry about the detonation issue? And would it help even more to switch over from 95 to 98 octane?

Why run on 95 when you can use 98? Does it harm the engine or car in any way since everything is setup to run on 95? Or is price and polution the only reason to use 95?

I'm really clueless to all this fuel types, running lean and whatnot when it comes to a turbo setup.

Clearify please

[Supersprynt]

Heres the thing, there are 3 different methods of calculating octane. The UK using PON which rates the lowest octanes. Japan uses MON which is why they have higher octanes, the US uses RON which is an average of both. It seems that because you are high, you are using MON. Which is weird considering your closer to the UK than Japan, but you may wanna look into it. Our 93 could be your 98, its just a method of calculation.

Now saying 10psi is kinda vague, one what engine. Do you have a 3sge? If so you could probably achieve that pressure however I'd say switching to the highest octane is crucial to fighting knock. You ask why use 95 when you could use 98? Well a couple of reasons. MOST cars (at least here in the states) are tuned and designed for 87, not 93. So some cars dont perform optimally on that octane. Secondly, price. Here its 30 cents more for 93 than it is for 87.

To avoid detonation, you'll want proper fueling, and proper cooling. It happens when the engine gets to hot, and starts igniting fuel in the combustion chamber at the wrong time. Switching to a higher octane is a helpful way in deterring knock, but you also want to have an efficient intercooler also.

[Illyont]

Thanks alot! That clear things up a bit