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Discussion Starter #1
I put 87 octane in my SRT-10 by mistake and didn't see much difference.

This was in a near empty tank.

No knocking or anything.

What effect would running cheap gas have in the long run?
 

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low ocgtane

i think over a period of time, impurity build up and valve probs...the owner manual i believe says min octane 91..
 

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Impurity Build-up?

Don't understand that? I think 87 octane is just as clean as 93 octane.

You may have valve problems down the road if you like to run the truck hard (Like the rest of us ;) ) as it will probably detonate with 87 octane. I doubt it's anything our ears can actually hear, but that doesn't mean it's NOT happening.

Now, if you baby your truck, never use any more than about 1/4 throttle and never rev it over 3K or so, you'll probably be fine with 87 octane. But what fun is that?

Then again, with today's distributorless ignitions and electronics, I don't understand why the engineers can't program the engine to retard the timing to the point where 87 octane will work? Sure, you'll lose some performance, but that would be your choice.
 

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I think one time won't hurt. Just burn this tank and don't do it again. :D It's not like any of us have done something like that ourselves. :rolleyes:
 

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Iam not totally sure, but I think the computer backs down the timing when it detects knock it the engine.
 

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drf said:
I put 87 octane in my SRT-10 by mistake and didn't see much difference.

This was in a near empty tank.

No knocking or anything.

What effect would running cheap gas have in the long run?

It's totally dependant on timing. The more advanced the timing the higher octane you need, the more power you make. The more retard the timing the lower octane you can run without predetonation. One would believe if you buy a srt10 viper or truck performance would be your primary objective. So to me if you wanting to run **** gas in a race truck you should have bought a mustang.
 

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begood said:
Iam not totally sure, but I think the computer backs down the timing when it detects knock it the engine.
9 is right 04 = no knock sensor
05 = has knock sensor

Once in a while ain't gonna hurt ya..
 

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Discussion Starter #9
Burnt the 87-octane out (was only 10 gallons).

Filled her up with 94-octane Sunoco - all is well.
 

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Adding octane boost

Has anyone added octane boost to there gas? According to the instructions 1 container of octane boost will raise a tankfull octane up 3 or 4 points. Has anyone tried it?
 

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It Works

456 said:
Has anyone added octane boost to there gas? According to the instructions 1 container of octane boost will raise a tankfull octane up 3 or 4 points. Has anyone tried it?
Just a pain-in-the-azzzz to have to put another $10.00 worth of fluid in the tank everytime. That's the ONLY way the NOS in the '95 Dodge would work. They put a PCM that had to have 92+ octane to work. In California that means boost the fuel. And $10.00 worth only does 16gals. of gasoline. I even put 3gals. of there 100 proof on top of every tank of gas. Put me @ about 100 octane. Just what the NOS likes.................
J.J;-(
 

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Just a word in here so that some of you may consider, and maybe we can get BOOMER to chime in here. In my race bikes I run VP fuel, and the difference isn't always the octane rating but the oxygen content. The octane rating should go with the amount of compression and timing you are running, but the more oxygen you have the more power you will make. Just for instance with pump gas my duc makes about 159rwhp and when I use MR9 and tune it to the fuel I get 167rwhp. Now I believe some fuels you have to tune for and others are just drop in such as VP U4. Just dropping U4 in and no adjustments I got 164rwhp. So I have never checked in on fuel for street cars but I know its out there. By the way The U4 Goes for about $57.00 for 5 gallons and the MR9 was close to $300.00 per 15 gallon, and I usually went thru about 10-15 gal a weekend depending on the track.I'm sure BOOMER being on a factory team may be able to give us more insight on the fuel, but I have heard with street cars you can gain up to 20rwhp but like I say I'm no fuel man, I leave that up to my engine builder.
 

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ugh I hate octane boosters....

Make your own...
improve octane substantially, clean off tarnish and carbon buildup on injectors and valves and pistons., I do this once a year in all my vehicles as a quick tune up

Xylene (117 R+M/2 octane) & Toluene (114 R+M/2 octane) are the most effective of the commonly available 'boosters' & can usually be found at paint supply stores like Sherwin WIlliams or Duron for $25 ~ 35 per 5 gallon can. The following is the most cost effective 'ratio' for using these products:

1 gallon of booster for every 3 gallons of pump gas

SOOoo for Xylene: (117 * 3) + (93 * 9) / 12 = 99 octane final mix

And for Toluene: (114 * 3) + (93 * 9) / 12 = 98.25 octane final mix

You also need to be sure and add ~0.5 ounces of a top cylinder lube such as Marvel Mystery Oil per gallon of booster. The lubricants normally found in pump gas WILL get diluted by the xylene / toluene & the MMO will bring it back up to spec. AN added benefit of running a xylene / toluene blend is that they are excellent fuel system cleaners & over a few tanks will remove 99.9% of any varnished old gas residue in the fuel system AND carbon buildup in the combustion chamber.

Keep in mind, you'll need to get a re-tune to take advantage of the extra octane, anyone dumping it into a bone stock ride & expecting to go faster will be sorely disappointed.



Octane rating is a measurement of a gasoline's resistance to pre-ignition (detonation, ping, knock, etc..) & is measured on a calibrated, variable compression ratio, single cylinder engine commonly called a knock motor or octane engine. There are many different ways to raise the octane number of gasoline, such as adding an aromatic hydrocarbon like xylene (117 octane) or toluene (114 octane), MTBE (which replaced the last two a few years ago, is ~112 octane and is now being replaced by more expensive methanol / alkylate blends.)

Tetra-Ethyl Lead is gram for gram, the most potent octane booster out there. Unfortunatley it also poisons the environment, is dang hard to get, highly toxic to the human nervous system, very expensive & coats your spark plugs, O2 sensors & catalytic converters with a nice layer of uncombusted lead.

Your best bet for making a homebrew racegas is the "formula" I gave earlier in this thread, a 1:3 mix of xylene to 93 pump gas will net a 99 octane final mix & (I know this is apples to oranges) is enough for me to push my Turbo Buick to 11.4'[email protected] running 22~23 lbs of boost & a moderately timed (20°) chip. Some guys swear by the TORCO additive, but from the evidence I've seen/heard it has a big slug of MMT in it.

--------------------------------------------------------------------------



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And from Rich Lassitter's article in the GS Xtra ... how to mix your own brew:
Formula (R+M)/2 Cost Mixtures with 92 Octane Premimum Note
10% 20% 30%
Toulene 114 $2.50/gal 94.2 Octane 96.4 Octane 98.6 Octane (1)
Xylene 117 $2.75/gal 94.5 Octane 97.0 Octane 99.5 Octane (2)
Methyl-tertiary-butyl-ether (MTBE) 118 $3.50/gal 94.6 Octane 97.2 Octane 99.8 Octane (3)
Methanol or Ethanol 101 $0.60 - $1.75/gal 94.3/94.7 Octane Not Recommended Not Recommended (4)
Isopropyl Alcohol and Tertiary Butyl Alcohol 101 $0.60 - $1.50/gal 94.5 Octane Not Recommended Not Recommended (5)

Notes:

Toulene: Common ingredient in Octane Boosters in a can. 12-16 ounces will only raise octane 2-3 *points*, i.e. from 92 to 92.3. Often costs $3-5 for 12-16 ounces, when it can be purchased for less than $3/gal at chemical supply houses or paint stores.

Xylene: Similar to Toulene. 12-16 ounces will only raise octane 2-3 *points*, i.e. from 92 to 92.3. Usually mixed with Toulene and advertised as *race formula*.

Methyl-tertiary-butyl-ether (MTBE): Oxygenate. Very common in octane booster products. Has lower BTU content than toulene or xylene, but oxygenate effect makes the gasoline burn better and produce more energy.

Methanol or Ethanol: Methanol is wood alcohol. Ethanol is grain alcohol and found in Gasohol in 10% ratios. Both alcohols are mildly corrosive and will eat gas tank linings, rubber and aluminum if used in excessive ratios. Main ingredient in "Gas Dryers", combine with water.

Isopropyl Alcohol and Tertiary Butyl Alcohol: Similar to Methanol/Ethanol. Isopropyl Alcohol is simply rubbing alcohol.

Making your own
How to make your own octane booster (this is the basic formula of one of the popular octane booster products). To make eight 16 ounce bottles (128 oz = 1 gal):
100 oz of toulene for octane boost
25 oz of mineral spirits (cleaning agent)
3 oz of transmission fluid (lubricating agent)

This product is advertised as "octane booster with cleaning agent *and* lubricating agent!". Diesel fuel or kerosene can be substituted for mineral spirits and light turbine oil can be substituted for transmission fluid. Color can be added with petroleum dyes.



If you need more info, let me know.
 

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Oh one last thing...

You can always go to the local airport and buy aviation fuel. You'll need to add some MM (marvel Mystery Oil).
I used to run this in my Banshee before I sold it
 

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Thanks for the info. WIKDSTV.. I'm looking into as we speak. Got buy VEC first and then we can play a little chemistry. Thanks again.. :cool:
 
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