Hi guys. I'm about to get an auto TL in less than a month. This has probably been discussed, but I was wondering whether the TL could take mid-grade gas. Thanks.

 

91 octane is required, but higher octanes can be used.

 

dont get anything less then the recomended 91 and you should be fine... problems arise when you use lower octane. When I went test driving the G35, the sales man had a fun time chewing on that his line of cars used the cheaper gas... blah blah blah it dosnt account to that much in the end.

 

If you really wanna use gasoline lower than 91, your car's ECU will retard your engine/ignition. Without spirit driving, your engine "might" be ok. We don't know...

I guess some ppl have used 89/87 gas since Oct... At least, I saw one SSM 04TLer fed her vehicle with 89 last week. Based on her age, I believe she won't do the spirit driving. :P I didn't want to say anything to her... feel sad...


IMO, I suggest to follow your owner manual, as Ron A had said above.

 

Last time I filled up a G35, the label under the gas flap said to use premium... as does my Qx4. Sounds like salesman monkeyshines...

 

crap really? damn they can be so convincing sometimes...

 

... sounds like a job for a VAFC and some tweaking to use lower octane gas.

 

The only reason the TL requires 91 or better is because of the compression ratio of the engine. 11:1 is stout by any measure for a street engine. Retarding timing does nothing to reduce compression but does reduce the damaging detonation caused by crap gas, this does not help the engine and in fact reduces MPG, Power and durability.

It's also why the TL is so tricky when it comes to supercharging.

 

We did a comparison between regular and premium with our Ram truck, which takes regular. We got better fuel economy with Premium, but not enough to justify the 20c price difference.

We've also noticed a difference in the ratings between Nevada and Utah - at some gas stations in Utah, their premium has a lower grading than in NV - I suspect it's because our gas comes from CA.

 

Well the reason your truck gets better gas mileage is simple it runs more effiecient. With todays computerized cars they do everything from advance and retartd timing to adjust air fuel ratio. So when your truck is running with 93 octane gas it can mix it effiectiently to get what it needs. When you use 87 gas it uses more fuel than air to get a efficient burn, hence the reason for the poor gas mileage. This is not true on all cars but for the most part it is. Compression Ratio has the most to due with what type of gas you can use though.


As far as the diffirent octanes at gas stations that is mainly the stationes and the states. When I used to live in pennsylvania we had Sunnoco's that had 87, 89, 93, and ultra 94. Im not sure if they still do that or not.

 

I put in 91 octane. We were getting 22.8 MPG. All of a sudden we were getting 21.8 MPG. It turns out that when my spouse fills the tank, she was putting in 89. The mileage difference is 5% the cost difference is less than 5%, so we really weren't saving much money.

Your cost savings is perceived. Since it is better for your car to put in the 91, don't go cheap.

 

We always use the gas that the vehicle's rated for, except for the one time I got caught out with the lower rating in UT. All the Japanese cars and trucks we've had asked for the higher octane - so that's what they get The truck's so dang thirsty, tho (35 gallon tank and 12 mpg)!

A

 

It seems that triple digit octane unleaded has not been discussed on this forum for a few years (at least by doing a search for this topic).

I use premium (93 octane) exclusively. While filling up at the Mobil station, however, I noticed 100 octane "racing" gasoline, billed as CAM2 by Mobil. Has anyone had any recent experience with such high octane fuel?

My guess is that it would not noticably affect performance in my 04 TL and it may even hurt the engine in the long run. Unless it really boosts performance, it would be tough to justify the $5.90 per gallon price tag. It's probably more effective in cars like the Dodge Viper, etc.

Any thoughts?

 

I went to a shell out here in CO that has 112 octane racing fuel. Tried it and didn't seem to make much of a difference, actually seemed to burn faster than regular gas. then after I had filled up my tank some I realized that this was LEADED gasoline.....last time for 112!

 

I rebuilt an old mustang and the motor was decked out. It would barely run on 93 octane due to the compression ratio so I would mix 93 and cam2 in and it would run pretty good. If I was going out to play I would fill it all up with cam2. Thats when she would really start to purr. As far as putting "RACING FUEL" in your TL once in a while it probably is not going to hurt it but your not going to get any real benifit. the car will have to advance the timing to get optimal burn though so you may pick up a little get up and go. In the long run you take the risk of burning a valve or something of that nature just stick with the 93 and some fuel/octane boost. Hope this helps

 

Should be okay, but the higher compression of this motor means it should have higher octane fuel. The engine should compensate for lower octane, but as the car gets older and you start putting significant mileage on the engine, I would stick with higher octane.