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Was going to run some 110 octane in 600 sdi and wondered if it would adjust / advance timing like it does between 87 octane and 92. I beleive this is done through knock sensor.
 

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Why do you want to run 110?
"If" your only reason is thinking it will go faster it will not, slower if anything.
Other than that I have no idea if it will adjust.
I know a few people that think more octane more speed but it dont work that way.
 

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No, the higher octane would be useless in the SDI's. The computer will adjust up to 92 octane. Anything higher will not Doo much other than making the exhaust smell a little better. I don't think it would harm the engine using 110, but it wouldn't help perfomance any.
Buy a mod sled if you want to run 110 octane fuel.
 

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The short answer is no. I asked a similar question and posted it in the brp corporate section. I asked if the sdi could countinue to increase timing based on increasing octane of the fuel. They answered, but not with a yes or no, and from the answer I gathered that there was no benefit to increased octane because timing had two settings rather than continuing to advance based on the fuels resistance to detonation (octane). I also asked a question a month or so ago on this forum inquiring whether any sdi owners had done any comparisons of performance of their sdi running on premium vs regular fuel. I got no confirming answers. I have since run only 87 octane in my 05 sdi gade after having used only premium for the first 4800 miles. I have now used the 87 for about 700 miles and I believe it now runs better than it did on the premium. I have moved the clicker down one and my mileage is at least as good as on premium. To benefit from additional octane you need additional pressure/heat in the combustion process otherwise it is of no value. I am at 145 psi compression with stock timing. I feel that I don't have enough pressure or timing to benefit from the higher octane in my sled. I think because the knock sensor has not acted to retard timing I am operating at the highest of the two timing settings and taking advantage of all available combustion of the 87 fuel and therefor there was no advantage when I was using the premium..
 

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There is no need for 110 octane when just increasing the timing. If I remember correctly the 600 SDI will only advance 4 degrees and you can run a 4 degree advance on pump gas no problem.
 

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Running high octane on a low comression motor is useless, not going to do any good.

The reason the computer adjust for 87/92 oct is because when you first fire it up it always starts with the 92 oct mapping and if the knock sensor picks up any noise it goes to 87oct mapping. Therefor the computer will not adjust to any higher octane unless it is programmed to do so.

So you are better off throwing regular pump gas in it!
 
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