Does anyone know what accounts for the different minimum octane ratings required between the two models? Just curious

 

2003-2004 AT and MT i believe is 87 octane or higher, (premium for maximum performance)
2005-2006 AT 87 or higher (premium for maximum performance); 2005-2006 MT - 91+ premium only.

2005-2006 MTs had rev-up VQ35s which requires premium only.


Bottom line run premium gas regardless of year in any G35..

 

In 60k+ miles I think I've maybe filled two tanks with premium.

 

All the VQs will run fine on 87, but you will see reduced performance. 91+ is the recommended fuel for all G35s if you want maximum performance. Dyno plots of VQ30 4th gen Maximas (96-99) running 87 see about 10whp/10wtq less than running 91. Below 4000rpms, there's no difference. In the upper rpms is where you'll see the difference. Running 87 may also result in worse mpgs because the knock sensor will richen the mixture to cool the combustion chamber if it sense excessive knock (which you probably won't hear).

 

I thought the rev-ups needed 91?

 

Me too, thats why I started this thread!

 

That would be news to me, but I don't have a RevUp owners manual to know for sure. Regarding the non-RevUp, I think there's some confusion on this site about interpreting Nissan's recommendations regarding fuel. The minimum requirement is 87 octane unless you're in an ultra high elevation environment which means you could potentially get away with as low as 85. However, 91 is recommended for peak performance and mileage.

 

I have a 2005 and my owners manual states at least 87 for the AT. For the MT owners (which have the rev-ups) it says 91 or higher only.

I have an AT but I feel better putting premium in there.

 

Here where it is very hot in the summer I think all VQ owners will have some performance gains from 91+. You would get away with it more in the winter.

 

so if you have a g35 you will need to put premium gas in? regardless what kind of transmission?

 

hey.. can u tell me y it is ok to run lower octane in higher elevations?
because i just moved to CO and every octane is 2 points lower than "normal" areas. (ie 85/87/91 vs 87/89/93)

 

Most "normal" areas I've been in are 87/89/91. I hardly ever see 93 here in Oklahoma.

Up in Nebraska yesterday I bought the 89 octane 10% ethenol blend because it was 41 cents/gallon less than the 90 octane at the station I was at.

 

Yes, it is fine to run lower octane at higher elevations due to the reduced oxygen content in the air. I'd probably use at least 87 and if I had 91 available, I'd use it because they ECUs can take advantage of the higher octane and at the higher elevation, you need all the power you can get. What's the altitude like in your neck of the woods? I'm suprised to see that they do offer 91. I can only find 92 at BP here in Kansas City and the rest of the shops carry 91. Elevation here isn't that high either (1000'-1,500'). I miss Atlanta where I could get 93.

 

Shell v-power ftw!

 

You bumped a 3 year old thread for that?