What octane gas?

[johnathanrn]

Hi all. I have a 2008 SEADOO challenger 230se with the supercharged engines. i use 93 octane...is it fine to use 87? Or do I have to stick to 93?

 

[KK40384]

Seadoo says they will run on 87 but recommend using premium (91+).

 

[timeman]

I always use the higher octane, however, I have run a tank or two of regular (87) when the marina was out of premium and didn't notice any difference....

 

[Coastiejoe]

Costco 91 octane is what I always use. The member price alone is worth it if you only buy gas as it is often 20 cents lower per gallon. Between two vehicles, gas cans and two 4-tech skis I save a decent amount if money.

 

[Dr Honda]

On the supercharged 4-tec... you need 91. They CAN de-tune themselves if you put in 87. BUT... if the knock sensor is going bad... and the MPEM doesn't lower the timing... you can burn a piston.

Personally... if you paid for the performance of the SC engine... don't take the chance by putting 87 in it. The lower grade fuel should only be used, if the better fuel is unavailable... and then I DO NOT recommend going past 70% power to be safe.



on the NA engine... 87 is fine.


That's my story... and I'm stickin' to it.

 

[pkturbo]

On the supercharged 4-tec... you need 91. They CAN de-tune themselves if you put in 87. BUT... if the knock sensor is going bad... and the MPEM doesn't lower the timing... you can burn a piston.

I am confused by your comment. My 2012 SC 255 C180 has a sticker by the gas cap that specifically states to use 87 octane gas. I understand that you can get (slightly) better performance by using 91 octane, but is it really a risk to use 87?

 

[KK40384]

On the supercharged 4-tec... you need 91. They CAN de-tune themselves if you put in 87. BUT... if the knock sensor is going bad... and the MPEM doesn't lower the timing... you can burn a piston.

I am confused by your comment. My 2012 SC 255 C180 has a sticker by the gas cap that specifically states to use 87 octane gas. I understand that you can get (slightly) better performance by using 91 octane, but is it really a risk to use 87?

What he means is that if you're running 87 in your SC motor you're relying on your knock sensor to detect detonation and retard timing to prevent said detonation. If a knock sensor was to fail, which they can, you're very likely to cause catastrophic damage to your engine in the form of shattered pistons. Been there done that (automotive application but the cause and effect were the same). In any boosted motor (SC or Turbo) you should be running premium. I'm willing to bet that in your owner's manual it says somewhere that you CAN run 87 but premium is recommended. That what my manual for my 08 says. And yes I do have the same sticker by the gas cap that you make a mention if. If you invest so much of your hard earned money into your boat why risk ruining it over a few pennies per gallon?

 

[Dr Honda]

Yep... what he said.


If your intercooler gets hot... or the air is dry... then the margin isn't there. 91 is safer with boost.


They are designed to run on 91... and "De-tune" to 87. With the non-SC engines... 87 is recommended, and you don't get anymore power running the higher Oct fuels.


Besides... as I was saying... if you paid the extra $$$ for the SC... why try to save a few $$$ on fuel. Generally, you are only looking at about an extra $6 per tank. What's $6 when it's $100 or more to top it off??