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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Octane booster....hurt performance?

  • Thread starter Thread starter Fett
  • Start date Start date Oct 12, 2006

Fett

New Member
Nov 2, 2004
766
6
0
Oct 12, 2006
#1
  • Oct 12, 2006
  • #1
Can too much octane booster cause performance problems?

Let's just say that a full bottle of octane booster....one that claimed an increase of 10 actual octane points....was somehow poured into my tank when I only had half a tank of gas. So basically a bottle that treats 25 gallons was added to roughly 7 gallons of 93 octane.

My car started running really crappy after my second pass at the track, and I checked spark and fuel. Basically it felt like I had a LOT less power than I normally do. I took it out on a test road a few nights ago, and as I would climb above 3k RPMs at full throttle...you could feel the car loose power, gain it back, then lose it again....causing almost like a surging. Not normal.

Then when I tried to see what it would do from 1st through 3rd. Normally, if I take off normally and go to full throttle slowly at 2k, it will break the tires loose at around 4k, then a quick shift, and the tires won't grip again until around 2.5k in second. Basically it tears the tires off the car. But the other day, it barely spun during a hard 1-2 shift. The long and the short of it is, it didn't feel as powerful at WOT as it normally does.

I let it run to E, then added half a tank of 93 octane, and the car feels better. Which is making me wonder if the octane boost was the problem.

It was stupid to add it, I know. I have no excuse for my stupidity...I know better.
 
G

GTOreturns

Well-Known Member
Oct 1, 2003
51
17
59
West Coast Best Coast
Oct 12, 2006
#2
  • Oct 12, 2006
  • #2
Yeah,that was over kill. 93 octane is fine for stock 5.0's, even advancing the timing to 14-15 degree's.
 

bubba-dough

Active Member
Dec 28, 2004
1,044
2
38
Indiana
Oct 12, 2006
#3
  • Oct 12, 2006
  • #3
Yes. The higher the octane the slower the burn. So unless you were "tuned" for it, it hurt you. Its like running racing fuel to a "stock" car.
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
2
58
Port Elgin, Ontario
Oct 12, 2006
#4
  • Oct 12, 2006
  • #4
to much will hurt performance for sure...I run 91 with my timing at 13*.....But I can still run 98 with very little pinging
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 13, 2006
#5
  • Oct 13, 2006
  • #5
I agree. An meaningful increase in octane would likely need an increase in timing advance to reap benefits. And if the jump was enough, performance can actually decline if timing was not advanced.

An analogy: let's say that you dont ping on 87 octane and 14* base timing. You then lower base timing down to 8*while staying on 87 octane. The car will not run as well as it did before. You kinda did that but with changing octane rather than timing.

On the other hand, I bet your fan was working great between runs.
 
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