What gas octan to use with 1998 grand prix gt v6 3.8L ?

What gas should I use for my 98 grand prix gt 38L v6?

I used regular until now. If it DOES need a premium is it bad to keep using 87?

Your 98 3.8 v6 GT is fine running on 87 octane, thats all thats required for a stock naturally aspirarted 3.8 v6 98 Grand Prix.
You normally would only have to worry about running premium fuel if your 3.8 v6 was supercharged(GTP)

na or sc? NA 87 octane, supercharged 93 octane.

Originally Posted by dsmuts

na or sc? NA 87 octane, supercharged 93 octane.

Wouldn't the Premium 89/90/91 be plenty? At least around here, you'd need to buy Octane Boost just to achieve a 93.

Premium is 91 or higher

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Na gt = 87

Originally Posted by TJeno

Wouldn't the Premium 89/90/91 be plenty? At least around here, you'd need to buy Octane Boost just to achieve a 93.

Premium around here is 93 I wasn't thinking about the less fortunate lol

been using 87 in my GT for all 11 years we've had her...

But I see there's not a straight answer for what octan. What does the manual say? My car has 210k if regular is not good I don't wanna kill it.

Your manual will say 87, and your fuel door should say regular unleaded.

I have a 1999 3.8 myself, vin K ... no supercharger .. 87 octane is fine for it. Around here it is running $3.70
per gallon as of today. Exxon 91 is $3.99 per gallon

the thing about 91 for a gtp is 91 usually says +/- 2

Originally Posted by raverockstar

But I see there's not a straight answer for what octan. What does the manual say? My car has 210k if regular is not good I don't wanna kill it.

Do you have a supercharged car?

Originally Posted by TJeno

Wouldn't the Premium 89/90/91 be plenty? At least around here, you'd need to buy Octane Boost just to achieve a 93.

If you 91 octane is your premium, using octane boost won't get you to 93. It might get you to 91.2. Octane boost is a HUGE waste.

Originally Posted by Fivefingerdeathpunch

Na gt = 87

Originally Posted by Fivefingerdeathpunch

Your manual will say 87, and your fuel door should say regular unleaded.

lol you're really trying to get the point across

To the OP, the only reason you would ever run premium is for mods or if you're just that person who wants to waste money on a NA car.

I totally missed that it said gt in the title. Use regular unleaded gas 87 octane.