what fuel do I run non supercharged 87 or 91 octane

[spicymemelord1]

Hey I have a 2003 seadoo GTX 4 tec 155 looking online it says it can run 87, so far I have been running ethanol free 91. I would definitely be nice on the wallet to run 87 regular. What do you guys suggest?

 

[spicymemelord1]

It's also worth mentioning that I use a tank up within a week so it's not like it's sitting for a long time. Would probably still end the season using 91

 

[matt1t]

I have no official evidence but I run both as well depending on the need. If I know the kids are just going to burn through it, I run 87.

 

[skiasylum]

The 155 is a 10-1 high compression motor that needs high octane fuel and is prone to detonation. Pay now or pay later. Ernesto Calas recommends 93 premium. It seems backward but the supercharged 1503 can use a lower octane because it's low compression. The 155 has flat top pistons and the supercharged use convex/dish pistons.

 

[mikidymac]

The 155 is a 10-1 high compression motor that needs high octane fuel and is prone to detonation. Pay now or pay later. Ernesto Calas recommends 93 premium. It seems backward but the supercharged 1503 can use a lower octane because it's low compression. The 155 has flat top pistons and the supercharged use convex/dish pistons.

Not according to Seadoo...

As always, read the owner's manual, it is available for free online.
Per pare 45 of the 2003 manual...
Normally-Aspirated Models
Use Regular Unladed 87 octane.
Supercharged Models
It is recommended to use 91 octane for optimum performance.
As a minimum use regular 87 octane.