Type of gas

[cfra7]

I understand that the GT requires premimum gas. Does the 180hp turbo require premimum?

[CREWZIN]

The GT does require Premium gas if you want to take advantage of the full 220 hp, but can use middle grade and even regular if need be. The computer will compensate for the lower octane, but your HP output will be degraded. If you hear any kind of pinging from the engine, go up one grade from what your using.

The 180 hp Turbo was designed to run on regular gas and putting anything higher is a waste of money. If and when you add Stage 1, then you should start using Premium for the added hp.

[Mean Green]

Yep, 180 hp turbo lite is detuned to run regular gas. That's why there is only 180 hp. In a pinch you can run regular in a GT, but prolonged use will cause engine damage eventually. The GT pcm can only pull so much timing and retard so much knock, but it can't stop it all especially when punching it when needing to, getting on the freeway and passing other vehicles.

[bobs turbo pt]

i use the 89 octane and and all is fine

[Mean Green]

Originally Posted by bobs turbo pt

i use the 89 octane and and all is fine

You hope.

WOW! You're saving around a $1.00 a fill up.

[bados]

I had a turbo lite and it ran fine on regular gas. As a matter of fact, Chrysler even suggested to use it. The GT, however, has a high compression head and should be run on premium octane minimum 91. You could use mid grade, but perfomances suffers.

[funksoulkitty]

According to Chrysler.com both turbo engines have an 8.1:1 compression ratio.

The GT requires 91 octane because it was designed to run on premium gas. What this means is that the ignition map the PCM uses was created with more ignition advance under boost. This is because the higher the octane of fuel, the more advance you can run safely (ie, without detonation). When you run lower octane gas in a car that is using an ignition map for higher octane fuel, you are likely to have detonation while under boost. Detonation will destroy your engine over time. Even though your PCM will retard the ignition timing if the knock sensor detects detonation, you don't want to be running your engine that way. While in high boost situations for example (let's say you floor it), your PCM would not be able to pull out timing quickly enough, and detonation/damage would most likely occur.

[Mean Green]

Originally Posted by funksoulkitty

According to Chrysler.com both turbo engines have an 8.1:1 compression ratio.

The GT requires 91 octane because it was designed to run on premium gas. What this means is that the ignition map the PCM uses was created with more ignition advance under boost. This is because the higher the octane of fuel, the more advance you can run safely (ie, without detonation). When you run lower octane gas in a car that is using an ignition map for higher octane fuel, you are likely to have detonation while under boost. Detonation will destroy your engine over time. Even though your PCM will retard the ignition timing if the knock sensor detects detonation, you don't want to be running your engine that way. While in high boost situations for example (let's say you floor it), your PCM would not be able to pull out timing quickly enough, and detonation/damage would most likely occur.

Thank you. Very well said.

[quicksilverdon]

Originally Posted by funksoulkitty

According to Chrysler.com both turbo engines have an 8.1:1 compression ratio.

The GT requires 91 octane because it was designed to run on premium gas. What this means is that the ignition map the PCM uses was created with more ignition advance under boost. This is because the higher the octane of fuel, the more advance you can run safely (ie, without detonation). When you run lower octane gas in a car that is using an ignition map for higher octane fuel, you are likely to have detonation while under boost. Detonation will destroy your engine over time. Even though your PCM will retard the ignition timing if the knock sensor detects detonation, you don't want to be running your engine that way. While in high boost situations for example (let's say you floor it), your PCM would not be able to pull out timing quickly enough, and detonation/damage would most likely occur.

Absolutely correct! I just want to add - the GT also allows higher turbo boost, which is equivalent to having higher compression.

[bados]

Originally Posted by quicksilverdon

Absolutely correct! I just want to add - the GT also allows higher turbo boost, which is equivalent to having higher compression.

Very well said...and I stand corrected; the head is not high compression.