13' Eco Towing Performanec

Mike Up wrote:

Heisenberg wrote:
Without a tuner running higher octane fuel is a waste of money. The "computer" is programmed to run whatever octane your owners manual prescribes. Unless you have a tuner it will not properly adjust for the higher octane. I am an Instrument Technician.

I'm also an Instrument Technician and disagree with your statement.

OEM computer algorithms vs after market tuners do much the same things,
generally.

Just that their set points are not the same. Maybe some additional and
removal, but generally they do the same functions

OEM tune will have a preset octane number in it's look up tables and
is told to go as much advance as those tables says

If the protection preset points are reached, the OEM tune will back
off advance and other attributes till it's sensors tell it is now ok

So if towing HARD in harsh ambient conditions...it may want to knock
(pre-ignition, ping, knock, etc) so the computer will pull back advance

In those conditions, using a higher octane fuel will help. Then there
is more power because the OEM/stock tune will then allow more advance
up to the limits it's look up tables list

'More power', but both lower octane and higher octane gasoline has
the same BTU's per gallon (energy potential). Just that any ICE with
more advance will develop more PSI on the piston tops than one with
less advance

After market tunes do all that, but it's look up tables have been
changed to 'higher' allowed advance.

Why most after market tunes require higher octane when using their
performance setting. Also why many require a lower op temp, as high
temp is part of ping/knock/pre-ignition

Bottom line is that both OEM & After market tune changes ignition
advance according to it's sensors. Difference is after market tuners
have a different, higher pre-sets in their tables