Premium gas gives 2-3 more horsepower in turbo models (confirmed by Honda rep)

I just learned one new thing from a Honda rep conducting dealership training:

If you use Premium over regular gas in a turbo it gives you 2 to 3 more horsepower. It does not hurt the turbo to use regular but premium helps your pick up.

Makes sense. In doing the reverse the knock sensor will trigger the ECU to retard timing.

mjones5 said:

I did learn one new things from rep - if you use Premium over regular gas in a turbo it gives you 2 to 3 more horsepower. It does not hurt the turbo to use regular but premium helps your pick up.

Click to expand...

Correct! If you use regular unleaded, it will not hurt the vehicle, but it "retards the timing", which causes it to lose some power!

To get the full 174 hp, premium unleaded is recommended, but not required!

HondaMan - do you know where Honda hid the second "easter egg" ? The trainer asked because he doesn't know but thinks it is somewhere in the infotainment system.

Good to know. Wonder how much HP you'd get if you used race gas

05 Si said:

Good to know. Wonder how much HP you'd get if you used race gas

Click to expand...

Theoretically it will output even more HP than with premium gas, unless the ECU stops advancing timing at some point.

Will MPG be the same, though?

mjones5 said:

I just learned one new thing from a Honda rep conducting dealership training:

If you use Premium over regular gas in a turbo it gives you 2 to 3 more horsepower. It does not hurt the turbo to use regular but premium helps your pick up.

Click to expand...

Honda's lead power train engineer, Yuji Matsumochi, doesn't agree that there is any power advantage to using premium. See the interview starting at min 5:

mjones5 said:

HondaMan - do you know where Honda hid the second "easter egg" ? The trainer asked because he doesn't know but thinks it is somewhere in the infotainment system.

Click to expand...

No, but I saw that mentioned here!

I tried doing a search but have not come up with anything yet!

I think it's probably a good idea to use at least 89 octane if possible. I have a tune on my car that was "safe/programmed on 87". Well when I uploaded the tune I was on 91 until one fill-up I decided to see if going to 87 would do any wrong. The car drove the same for a while till a few days later when the 87 octane made its way through, the car lost a ton of power all throughout the rev band. If it were a really basic engine that didn't surpass the 100hp per liter mark, 87 all day long. But this engine seems fairly sophisticated and feeding it the higher octane would just assure things to run smoother

jks said:

Honda's lead power train engineer, Yuji Matsumochi, doesn't agree that there is any power advantage to using premium. See the interview starting at min 5:

Click to expand...

So the trainer might not really know what he's talking about on this topic? I'm sure the engine engineer knows what he's talking about

I would tend to agree with the engineer !

alls im sayin is why would you put in something that might be right at the threshhold of knocking when you can play it safe and possibly even benefit from a less timing pulls + a couple more hp

DrivenSoul said:

alls im sayin is why would you put in something that might be right at the threshhold of knocking when you can play it safe and possibly even benefit from a less timing pulls + a couple more hp

Click to expand...

How do we know that regular gas octane is at the threshold of knock though? If they recommend regular gas then I would think there's a buffer built in before knock occurs.

I'm just saying that you shouldn't dismiss higher octane based on my experience, I used to be the most non-believer of octanes and brands until I had some bad experiences. And like I said, over 100hp per liter means a lot is going on and it wouldn't hurt to use 89 to be on the safe side.
There could be the fact that they market it for 87 because people may complain if it required premium fuel.