Vibe GT Fuel ??

[labelle]

Hello,What kind of fuel shoul I use on my Vibe GT ??? Only Premium or Regular will do ???

[dlmetzger]

The GT requires high octane, I don't remember the exact minimum value but you should use Preimium.

[Ryan]

91 octane is the minimum recomended even though 87 octane can be used if it is the only grade available but for emergencies only. You should fill with 91 octane as soon as possible to increase the octane value in the tank and avoid heavy acceleration while using 87 octane. Also, if you are towing, it is recomended you park what you are towing and find a higher octane within 100 miles (I beleive). A possible solution is to carry a bottle of octane boost in case you need it.

[d_m_kolb]

You probably wouldn't have any major problems running regular because the computer is going to adjust the timing to prevent knocking. You will notice the loss of power from having the timing retarded so far and also loss of gas mileage. You'd be much better off to use the premium that the owners manual calls for. High compression engines need the higher octane. I think the GT is running around 11.5 to 1 compression.

[cohocarl]

quote:I think the GT is running around 10.5 to 1 compression. I think it's 11.5 : 1 if I read right. That's very high. I'd use as high of octane as possible. 87 would only kick in the knock sensors, and reduce ignition timing.

[d_m_kolb]

You could run 87 octane fuel if you had a water injection system. You wouldn't lose any power (you actually probably gain power and gas mileage) and you wouldn't have any engine knock. Water injection decreases the possibility of detonation by lowering the combustion chamber temperatures and increasing the effective "octane" of the fuel. This allows the engine to run a higher boost and full spark advance without the use of race gas. Additionally, if the water is atomized in the intake stream, there is an additional cooling of the intake charge. Both effects are increased with the inclusion of 50% alcohol to the mix (don't spray the exterior of an intercooler with alcohol!, this refers to internal injection only). The additional fuel of the high octane alcohol will in turn allow boost beyond what the factory fuel system can deliver. I have posted a explaination in engine tuning forum.