Re: [DML] Re: delorean fuel

[Owen Emry <owen@xxxxxxxxxxxx>]

> You're correct, but not entirely accurate - higher octane means a slower 
> burn but it does contain more chemical energy, therefore an engine 
> that's set up to take advantage of it will be more powerful than an 
> identical engine tuned to use regular fuel. If you run an engine set up 
> for Super on regular, it will damage it.

No, sorry.  No offense intended, but completely incorrect.  Heptane (i.e., the rest of the fuel) contains more chemical energy than Octane, so the higher the octane, the less chemical energy per unit mass.

The reason for the octane is that it's more compressible before spontaneously combusting -- thus it's necessary in high-compression engines where lower-octane fuel would auto-ignite before the spark.  (This is what causes the "knocking" noise.)  

High compression permits smaller engines to output more power, because the power is basically a function of how much fuel and air you can cram into the cylinder.  Higher compression ratios are one means of achieving this.  Forced induction (turbochargers, supercharges, etc.) are another.  None of this matters to your stock PRV, though, because it was designed to use 87 (RON) octane fuel.  Anything beyond that is really a waste of money.

Regards,
Owen





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