Engine & Internal Chat about beefing up your engine's insides here.

Regular vs Premium

  #1  
Old 05-31-2006, 09:29 PM
HCF Member
Thread Starter
Join Date: Sep 2005
Location:
Posts: 74
Default Regular vs Premium

Just curious....

Would there be much of a difference in using the premium (91) over the regular (87) in my 96 Si (EX)? It's pretty much stock except for the CAI with K&N. Any advantages or disadvantges of one over the other?

THNX
 
  #2  
Old 06-01-2006, 05:49 AM
Join Date: Jan 2005
Posts: 16
Default RE: Regular vs Premium

Octane ratings are pretty much just numbers correlating to detonation resistance. If you have 87 octane, you have an 87% octane rating with a 13% heptane reading. Heptane burns fast, Octane doesn't. If you have more octance, your gas burns "slower" on the combustion cycle. If you run 87 octance in a car that needs 100, you'll get detonation because the fuel is burning before it needs to, in essence. The basic rule is that the higher the compression, the higher the octane needed to resist detonation. I've seen built, boosted cars gain quite a few poines after swithing to race gas, but those are tuned, turbo'ed and street (il)legal. I wouldn't recommend switching gasses necessarily unless you have a real reason to.
 
  #3  
Old 06-01-2006, 07:51 AM
HCF Member
Join Date: Dec 2005
Location: Carmi,Illinois
Posts: 1,707
Default RE: Regular vs Premium

I would check you owners manual if your car is close to stock some cars are made to drive on different octane levels.
 
  #4  
Old 06-01-2006, 11:14 AM
Senior Member
Join Date: Apr 2005
Location:
Posts: 624
Default RE: Regular vs Premium

Unless you have alot of aftermarket upgrades I wouldn't spend the extra money, but that's just me. IT's not going to give you much gain if any on a stock ex.
 
  #5  
Old 06-01-2006, 12:58 PM
HCF Member
Join Date: Mar 2005
Location:
Posts: 7,702
Default RE: Regular vs Premium

theres really no point. you're just wasting your money.
 
  #6  
Old 06-11-2006, 11:13 AM
Join Date: Jun 2006
Location:
Posts: 24
Default RE: Regular vs Premium

you can also add a little bio-desil to your gas to rais the octane
 
  #7  
Old 06-11-2006, 11:54 AM
HCF Member
Join Date: Jan 2005
Location: Chicago, Illinois
Posts: 5,180
Default RE: Regular vs Premium

You could use high octane and advance your timing. That will give you a couple horses, but IMO its not worth it.
 
  #8  
Old 06-11-2006, 02:12 PM
HCF Member
Join Date: Feb 2005
Location: Jersey
Posts: 7,168
Default RE: Regular vs Premium

I wouldnt mess with the timing. Just run 87, I wish I could use 87.......its much cheaper.
 
  #9  
Old 06-11-2006, 09:20 PM
HCF Member
Join Date: Jun 2006
Location: USA
Posts: 1,193
Default RE: Regular vs Premium

Who told you that diesel adds octane???????????

Diesel is CETANE. Totally different kind of fuel, made for compression ignition.
 
  #10  
Old 06-11-2006, 09:44 PM
HCF Member
Join Date: Jan 2005
Location: Chicago, Illinois
Posts: 5,180
Default RE: Regular vs Premium

Diesel is too thick for your fuel injector to spray. But diesel does resist detonation more than gasoline. Typical compression ratios for diesel engines are in the 20:1 range.
 

Thread Tools
Search this Thread
Quick Reply: Regular vs Premium


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.