87 octane vs 93 octane?

[devildoc]

Originally Posted by turboguy327

I was getting 17 mpg around town. 23 highway on 87. I now get 19 around town and 26 to 27 on the highway with 93.

I agree with turboguy. I have the mods, and with 87 I am getting around 29mpg on a 45mi stretch that I drive to the track out here. When I did the last trip out I had "clean" tank of 93 in it and I got 32mpg on the same distance. So I believe the car runs better with higher octane.

[jagan323]

I'm sad, the gas station I'm used to filling up at used to have 94, but now they lowered it to 91 =(

[Edge.128]

i use 88 which is the "regular" gas around here. i used to put mid-grade or premium but i just stick to regular now for day to day. especially with winter coming there won't be much driving.....

[67 Convertible]

I've had my car 16 months with 17,000 miles. I've used 87 oct. since day one. I haven't reset the DIC in about 6,000 miles, and I'm averaging 23.5 mpg. (city 60%, highway 40%)

My car has plenty of power for a DD.
Would I have a little better performance with 93 oct.? Probably.
Would the added gas mileage running 93 offset the added cost for fuel? Doubtful.
Do I need more performance from my DD? No

I'll keep running 87, car runs great with no issues.

[RCLapCar]

Originally Posted by scrming

BTW... we have 93 octane, 100% gas here...

Yeah well we got 94 pure gas all over the place here. So take that.

On the topic I used to run 94 but switched back to 87 recently. I haven't really noticed any difference in MPG's or performance. Though if I know I'm going to the track (drag or road course) I'll run the tank dry and fill up with 94. No point spending the extra money if it's hardly going to be noticed day to day.

[Wizzer]

I found when I had 87 in it that when I had it under full throttle there was some power surges. Kind of like the timing was being adjusted on the fly and not to my benfit. With the expensive stuff I had the surging go away. I would say try two tankfuls and see if your car runs different where you live.

[mrray13]

Originally Posted by scrming

It's not really tuned for 87... it's more like the car is designed to handle 87... Basically it appears the car is "over sparked" and then depends on the knock sensors to bring the timing back down to the appropriate level for what ever octane gas you are running... So the old way of thinking that running higher octane doesn't do you any good because the car isn't tuned for it, really doesn't apply here.. The computer seems very adaptive compared to older setups where you had to have different tunes for different octanes...

But like you said... day to day driving you're not going to notice much difference... although your MPG should go up a a little bit with the higher octane gas...

BTW... we have 93 octane, 100% gas here...

Okay, get all technical on me, lol. At least I got the general idea right, and screw your 93 100% :middlefinger:

Originally Posted by ROD1

Brag more!

Originally Posted by RCLapCar

Yeah well we got 94 pure gas all over the place here. So take that.

On the topic I used to run 94 but switched back to 87 recently. I haven't really noticed any difference in MPG's or performance. Though if I know I'm going to the track (drag or road course) I'll run the tank dry and fill up with 94. No point spending the extra money if it's hardly going to be noticed day to day.

:middlefinger: for you and your 94 too! lmao.


Because of the mods on the car, I'll keep running 91 (90%) adn spend the extra money. Car seems to like me for it. However, if PacMan was still stock, it would be 87 or 89 for him.

[buddylok]

I use 89, 87 does give me a bit of knocking.

[GQ4Life]

Originally Posted by mrray13

Okay, get all technical on me, lol. At least I got the general idea right, and screw your 93 100% :middlefinger:








:middlefinger: for you and your 94 too! lmao.


Because of the mods on the car, I'll keep running 91 (90%) adn spend the extra money. Car seems to like me for it. However, if PacMan was still stock, it would be 87 or 89 for him.

unless car is tuned for 94 over 87 there's is no HP increase... If car is getting knock with 87 there will be a HP increase
Now get car tuned for 93 and get a nice HP bump.

[scrming]

Originally Posted by GQ4Life

unless car is tuned for 94 over 87 or get is getting knock with 87 there will be no HP increase
Now get car tuned for 93 and get a nice HP bump.

This is simply NOT TRUE! We have been over this many times. One guy here who owns a dyno actually showed some HP gain by running higher octane! As I pointed out, the V6 is OVER SPARKED! If you run 87 octane you will find that the knock sensors are very active and pull quite a bit of timing! Remember their job is to stop the knock before YOU can hear it in the cabin. Running higher octane, like 93 the knock sensors are less active! The old way of thinking that you have to be specifically tune for higher octane does not apply to this V6...

[GQ4Life]

Originally Posted by scrming

This is simply NOT TRUE! We have been over this many times. One guy here who owns a dyno actually showed some HP gain by running higher octane! As I pointed out, the V6 is OVER SPARKED! If you run 87 octane you will find that the knock sensors are very active and pull quite a bit of timing! Remember their job is to stop the knock before YOU can hear it in the cabin. Running higher octane, like 93 the knock sensors are less active! The old way of thinking that you have to be specifically tune for higher octane does not apply to this V6...

Actually that is exactly what I said."only a HP increase if u r getting knock with 87

Ok I wrote it wrong writing using cell phone. Fixed it.

[scrming]

Originally Posted by GQ4Life

Actually that is exactly what I said."only a HP increase if u r getting knock with 87

Ok I wrote it wrong writing using cell phone. Fixed it.

Here is exactly what you wrote:

"unless car is tuned for 94 over 87 there's is no HP increase unless car is getting knock with 87 there will be no HP increase
Now get car tuned for 93 and get a nice HP bump. "

Ok... let me rephrase things... The car appears to be "tuned" for higher octane right from the factory. The knock sensors however let you run 87 octane. The thing is unless you are monitoring the knock sensors you don't even know your car is "knocking" with 87!

There is no need to get a tune for 93! You can get an HP bump from 93 with the stock tune! You don't need a tune to take advantage of higher octane!

[GretchenGotGrowl]

Hey Scrming, do you think it is possible that these things are programmed to advance until they detect knock and then back off a bit? That would be cool, but probably just wishful thinking?

[GQ4Life]

Originally Posted by GretchenGotGrowl

Hey Scrming, do you think it is possible that these things are programmed to advance until they detect knock and then back off a bit? That would be cool, but probably just wishful thinking?

wouldnt be first car I have seen that is actually tune from factory advance a little and knock detector pulls timing couple degrees
SRT4's were this way. Suppose to be tuned for 91 but they got usually about 3 degrees of or so of knock.. run better at 93 and made more HP
The toys were best. Had button that you can put in 100 octane then hit button for a nice 30HP jump