Hey there! To spare some time I�ll get right to it. I got my 05� G35 Tuned with UpRev a while back, and have yet to try the 87 octane tune over fears of engine knock developing. I trust my tuner, very experienced and got me some great results, but with gas getting so damn expensive I�ve been looking at my 87 tune and wondering if its worth the risk. Anyone with experience or advice of any sort is welcome.

 

The car will protect itself, right? It's not like the tune disables the knock sensor and timing retard. I'm interested in this topic because I don't really understand how to interpret the data in the data logger that my tuner used to e-tune my car. I deliberately put 87 in mine and wanted to see the effect in the data logger and how the car responds. I don't see obvious knock sensor activity and corresponding timing changes when I think I should see them.

 

Anything under WOT and you will probably never see a difference.

 

OP you're overthinking this. The 87 octane tune will adjust the engine parameters to run safely on 87 octane. That's why you have it as an option.

 

The "higher risk" would be to use the normal tune with 87 octane fuel.

The 87 tune will have LESS timing advance and thus be "safer". The only reason I can think of to use that tune though would be if you were travelling across the country and end up at a backwoods gas station that only carried regular unleaded and no premium. Then you would shift over to the 87 tune, or in your case not wanting to pay extra for the premium fuel you can run regular unleaded without the extra timing advance.

 

Sounds good, I like the idea too.

 

In for this also, I've been looking for info only for economy and lower octane tunes however it seems most of the info out there is people with 20+ increases and crackle pop sounds.
I could care less for performance on this end and refuse to take the "This is an infinifi" garbage response.

This is a 3.5 v6 in a mid 3klbs. From a tuning aspect if you monitor AFRs on a vehicle it can let you know if it has the potential to save fuel while getting better performance.
The reason why most cars dont run leaner ratios is not because of melting pistons but higher NO2 concentrations in the combustion chamber which are bad for the environment.

These cars run insanely rich, 10.1-11.1 afrs at low rpms yet jump to 14-15s upon WOT, the data shows how Uprev is able to obtain such a horsepower increase and it's by fixing these.

When most people look/consider a tune is after BO's or to get more power, at the same time a tune can improve your airfuel ratios to provide better economy.
Any tuner can tell you there is no need for a bolted car to be running WOT Afr's at cruising speeds and if you are then your tuner only focused on wide open throttle.

Im excited that Uprev has these modes and how quickly it can toggle between them, I just haven't seen much data for people using these modes and their results.

 

I notice quite a bit of knock on both of my cars (04' and 05') with 87oct. I switched to E15 and it runs like high oct gas and datalogging shows zero knock. I didn't have to change the stock tune for E15 either, the ecu actually compensates very well. I actually picked up 1mpg mixed driving from the timing boost. Unfortunately a lot of people can't get ethanol like we have here.

 

Ive been running 87 octane in my car since October, when the weather started getting kinda cold. I havent had any issues yet and will keep running it into the summer. I do mostly regular driving with occasional WOT pulls here n there. If I do get any knock with the hotter temps, then I'll switch back to 91. My engine isnt modified or tuned in any way though.

 

FWIW I'm on my third Infiniti the first two purchased brand new and my current 2016 Q70 purchased used with 3450 miles all from the same dealer. This 87 octane debate has been going on at least since I purchased my first Infiniti the 2006 G35 6 speed manual in late December 2005 putting on 171796 miles and trading it in for my next Infiniti a 2012 G37S 6 speed manual that had almost 95k miles when I traded it in for my present 2016 Q70.
In all those miles I used regular 87 octane except for one month tests in my 06 G35 with 91 and 93 octane carefully monitoring my MPG as I made the same 100 mile commute to work every day all non stop highway miles on the NJ Turnpike and Garden State Parkway.
The results of those one month tests of higher octane proved to me that there was no reduction in performance, however there was a reduction in MPG as well as a higher cost in using premium gasoline.

I never waste my money using premium and my current Q70 runs just fine on 87 Octane.
Typical results of a round trip from NJ to Florida resetting the vehicle computer with each fill up. Short local trips in Florida clearly show the reduction in MPG for short trips vs highway driving



Telcoman