Gas for an L32
#1
Gas for an L32
I'm looking into a newer model Grand Prix (04 and up) for my wife so I've been hanging around ClubGP to get some questions answered. According to the GP guys a 3800 SC'd L32 (replacement for the L67) can run ok on regular fuel (with no knock) if the engine isn't modded. I downloaded the manual from GM Parts Link for an 04 GP.
The 04 GP manual says...
My 01 Bonne manual says....
Is it ok to run 87+ octane in a S3 3800 SC?
The 04 GP manual says...
If your vehicle has the 3800 Supercharged V6 engine
(VIN Code 4), use premium unleaded gasoline with a
posted octane of 91 or higher for best performance. You
may also use middle grade or regular unleaded gasoline
rated at 87 octane or higher, but your vehicle’*
acceleration may be slightly reduced. If the octane is less
than 87, you may get a heavy knocking noise when you
drive. If it is bad enough, it can damage your engine.
(VIN Code 4), use premium unleaded gasoline with a
posted octane of 91 or higher for best performance. You
may also use middle grade or regular unleaded gasoline
rated at 87 octane or higher, but your vehicle’*
acceleration may be slightly reduced. If the octane is less
than 87, you may get a heavy knocking noise when you
drive. If it is bad enough, it can damage your engine.
If you have the 3800 Supercharged V6 engine (VIN Code 1),
use premium unleaded gasoline rated at 91 octane or higher.
With the 3800 Supercharged engine, in an emergency, you
may be able to use a lower octane -- as low as 87 -- if heavy
knocking does not occur. If you are using 91 or higher octane
unleaded gasoline and you hear heavy knocking, your engine
needs service.
use premium unleaded gasoline rated at 91 octane or higher.
With the 3800 Supercharged engine, in an emergency, you
may be able to use a lower octane -- as low as 87 -- if heavy
knocking does not occur. If you are using 91 or higher octane
unleaded gasoline and you hear heavy knocking, your engine
needs service.
#5
Well here'* the deal. My wife just got a job about an hour away. She'* going to be in the car for two hours a day so she'* going to be putting some serious mileage on the car. She doesn't want to buy anything that runs on premium fuel. If the L32 in the GP will run on regular, I'll buy a GTP, if not, it'* going to be a NA GT.
#10
We did a little test on the GXP (different engine, I know). The book says it is fine to run regular, but better performance with premium. Over five tanks of gas with each type our mileage was so much better with premium that the differential between regular and premium would have to be about $0.50/gallon to make running regular more economical than premium. We were unable to detect the same difference for the 96 SSE (L36) so always run regular in it, although some people swear their L36'* run better on premium. I don't know if that is true or not.
So if your manual says you will get better performance (and mileage by default) with premium, it will be to your benefit to run premium. But I can see where fuel is a deciding factor. My daily driver is a 92 Nissan with two hamsters and a rubber band- about 32-34 mpg on regular. 0-60 ? Yes, that'* how fast it goes... from 0 to 60.
So if your manual says you will get better performance (and mileage by default) with premium, it will be to your benefit to run premium. But I can see where fuel is a deciding factor. My daily driver is a 92 Nissan with two hamsters and a rubber band- about 32-34 mpg on regular. 0-60 ? Yes, that'* how fast it goes... from 0 to 60.