Do i need to fill my car with 91 octane??

Thread Tools
 
Search this Thread
 
Old 05-29-2005, 07:57 PM
  #1  
New Member
Thread Starter
 
blue2.7turbo's Avatar
 
Join Date: May 2005
Posts: 152
Likes: 0
Received 0 Likes on 0 Posts
Default Do i need to fill my car with 91 octane??

I just bought a 2001 ming blue 2.7T Quattro i'll post pics once the camera is charged but i was wondering what kind of gas i should be puttin into the car

Thanx
Old 05-30-2005, 01:49 AM
  #2  
AudiWorld Super User
 
VerrÜckt's Avatar
 
Join Date: Feb 2003
Posts: 16,402
Likes: 0
Received 0 Likes on 0 Posts
Default Less than 91 octane will result in reduced performance and...

is arguably harder on the motor.

I wouldn't do it personally, but you could probably get away with it.
Old 05-30-2005, 06:30 AM
  #3  
New Member
Thread Starter
 
blue2.7turbo's Avatar
 
Join Date: May 2005
Posts: 152
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Less than 91 octane will result in reduced performance and...

i'll just play it safe and just use 91 octane
Old 06-06-2005, 09:08 AM
  #4  
AudiWorld Super User
 
paulroad's Avatar
 
Join Date: Oct 2003
Posts: 18,424
Likes: 0
Received 1 Like on 1 Post
Default Lower octane = lower MPG.

I did this test a few times with my 2.7T- 6 speed. I got 8% less MPG for 8% less cost 93 vs 87 so I didn't saving anything at all by going to lower octane.

The ECU adapts the engine to use the lower octane fuel without knocking/detonation.
Old 06-09-2005, 12:49 AM
  #5  
AudiWorld Senior Member
 
MikeyB09's Avatar
 
Join Date: Oct 2003
Posts: 1,144
Likes: 0
Received 0 Likes on 0 Posts
Default

Be really safe and use 100 octane!
Old 11-02-2005, 03:12 PM
  #6  
New Member
 
audiconvert's Avatar
 
Join Date: Nov 2000
Posts: 405
Likes: 0
Received 0 Likes on 0 Posts
Default I don't think that's right

1 lb of fuel contains about 18,000 BTU no matter if it's 10 octane or 100 octane. The main thing higher octane does is slow down the burn rate of the fuel/air mixture. This is needed at higher temperatures and pressures (hard acceleration) when the fuel/air mixture wants to explode rather than burn (a subtle difference). If it explodes you hear a knock.

All cars sold in the US are required by law to run at least on 89 octane. Your engine computer will sense knock and retard ignition timing which will reduce your max power potential.
Old 12-05-2005, 05:57 PM
  #7  
AudiWorld Expert
 
nyet's Avatar
 
Join Date: Dec 2000
Posts: 33,078
Likes: 0
Received 0 Likes on 0 Posts
Default

and use more gas hitting the target torque part throttle, since motronics is dbw
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
muscleknight
2.0T FSI Discussion
6
11-10-2018 04:51 PM
S40RCE:Smurf
S4 / RS4 (B5 Platform) Discussion
11
11-18-2005 07:33 PM
tphillips
Audi 100 / A6 (C4 Platform)
1
09-28-2003 02:03 PM
Milpitas2.7T
S4 / RS4 (B5 Platform) Discussion
27
11-04-2001 03:44 AM
Audi juice
A4 (B5 Platform) Discussion
5
10-29-2001 08:37 PM



Quick Reply: Do i need to fill my car with 91 octane??



All times are GMT -8. The time now is 02:01 PM.