I ran the 6MT with 87 Fuel after I ran the 93 Fuel to the light, and then ran it until the light came on, and then put in a 93 fuel again.

After running both, I probably will never put in 87 octane fuel again, since there is a significant difference.

Major difference is clutch engagement from stop. I can engage the clutch much smoother with the Premium fuel. With regular fuel, I would engage the clutch and RPM will drop until it almost stalls, but with premium, that doesn't happen at all. I don't have to give it as much gas on premium fuel to engage the clutch, which is also good for the clutch.

So with that said, I think TSX fuel door says "PREMIUM FUEL ONLY" for a reason. I didn't notice any changes in WOT maneuvers.....

 

Use what works for you. I use regular gas and have no problems. I also drive a 6MT tsx. It now has 88,000+problem free miles.

 

I don't get why people put less then premium in their TSX's, it's only a $5 difference in filling up (at most). Seriously, how cheap can you get? Why buy a nice car and not even put in the correct gas?

 

I tried using 91-93 octane for over two months-no improvement in performance or gas mileage. We previously owned two other cars that recommended (not required) premium gas. When we sold the cars, our 1991 Mazda Mx-6 GT had 250,000+miles and our 1998 Eagle Talon TSI-AWD had 125,000+miles. They both had their original engine, turbo, clutch, transmission and ran excellent using regular gas. I have all the service done by a acura dealer. To many that is a waste of money. I also do not mod my car as I think it is beautiful the way I bought it. I average 30,000+miles a year.

 

I really have to agree the TSX runs a lot better with premium. Granted its a Honda so premium or regular it will last 300,000 miles. I believe Acura says premium for a reason and I will adhere to their recommendations. The TSX has a compression ratio a little to high for regular, also when the price difference is minimal why use the 87? I can afford not getting morning coffee a couple times a week to have a little bit better fuel economy, performance and piece of mind. If you run regular that's fine, its your car. Just an FYI this is one reason why I have sworn off buying used cars, you never know how the car was maintained before, even with extensive "dealer" records.