Has anyone used the middle grade gas with their Z? any problems? any advice?

Sorry if this has already been mentioned....

 

Use regular, the main advantage of premium-grade gas is that it allows automakers to advertise a few more horsepower by designing and tuning engines to take advantage of premium's anti-knock properties. But auto engineers generally agree that if you use regular in a premium engine, the power loss is so slight, most drivers can't tell.

Today's engines use highly evolved versions of a device called a knock sensor to adjust settings automatically for low-octane gas. And more engine control computers have adequate memory to allow separate sets of instructions for various octanes. The engine control computers keep pushing to maximize performance on whatever grade of fuel is used.

The only modern engines that should really need premium are those with superchargers, which force-feed fuel into the cylinders. "You're driving along and just tramp the gas and the knock sensor cannot sense the knock fast enough in some cases," because the supercharger boosts pressure so fast, says Bob Furey, chemist and fuels specialist at General Motors.

Burning regular when the owner's manual specifies premium won't void the warranty, nor damage the engine, even the most finicky automakers say. "You're giving up perhaps just a little bit of performance that a customer wouldn't really even notice, it's so slight," says Furey.

All Porsche engines are designed for premium, too, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using regular gas, even in the highest-performance, regular-production Porsches.

Premium, in fact, sometimes is worse fuel than regular. It resists knock because it's harder to ignite than lower-octane fuels. As a result, some engines won't start as quickly or run as smoothly on premium, notes Gibbs, the SAE fuel expert.

High-test does have a potential fuel economy benefit. It is slightly denser than lower-octane gas, meaning there's a little more energy in a gallon. But the small difference is hard to measure in real-world use, and that same density can contribute to undesirable buildup of waste products inside the engine.

http://www.usatoday.com/money/autos/...emiumgas_x.htm

 

Why??

Saving a dime a gallon isn't worth it.
You're worried about spending $1.70 or $1.80 more each tank??

 

Thanks, I read that in your other post.
So do you use Regular or Middle grade in your Z?

 

I use regular, also use regular in my BMW 325 and I've never had a problem. If you race definitely use a premium-grade gas. My boss uses regular in his Z06 with no problems. As you can see premium users are passionate.

 

but if it runs fine on middle grade, then what's the difference? I am just asking if anyone else has used it.

 

From the Owner’s manual: My question, again, why would you want to use regular or a ‘mid-grade’ gas?? The only conceivable reason is to save a couple bucks each tank full. I don’t understand the logic. Dude, you have a $30,000+, high performance, sports car. Nissan’s engineers know more about the Z than me or anyone posting here. Why not just go with the Nissan’s recommendation?

This isn’t the first time this question has been posted on the board. Sorry, but I just don’t get it…