Injector Cleaner + Octane booster, not a good idea

[BAsque1]

Have a friend with Cobra with FI he added a full tank of regular gas and to it he added octane booster and 15 oz of fuel injector cleaner. The car now has a bad missing as if the gas mixture was diluted. He then used up about 1/4 of a tank and added 5 gals of premium gas . The performance improved a tad but still doing the missing.
Any thoughts short of siphoning all this gas?
Tks
Lou, II
PS
The car was performing fine before, this was as a preventive maintenance, the injector cleaner that is.

[RedEye]

I would find out what the octane effect is with the injector cleaner. If its solvent based it could slightly reduce octane, but my guess is that it probably increases octane just slightly (causes fuel to burn more slowly). Normally when I take on really high octane (have a 331 stroker with Holley DP) such as leaded 110 octane racing fuel, I can lose as much as 200 rpms on idle. The engine will idle down to 450 or so when I'm normally between 650-750. If I get a tank of 'bad' gas at the normal premium pump it'll do the reverse. I don't know how well this will be expressed with FI, but I would ad a few gallons of minimum octane fuel and stand by with more boost if ping develops.

[Tim Brewer]

Nothing wrong with octane booster, although most do nothing. But the question is, why would anyone buy regular fuel and add a booster to that? Always purchase premium and add a booster to that if you want. That's what I do, I use Lucas octane booster.

[Gaz64]

I would not have added two cans of any "additive" at the same time to a "bottom of the ladder" fuel.

Is the engine misfiring on one or more cylinders, or surging across all cylinders?

Some injectors have a filter screen that aren't compatible with additives.

Premium fuel is the only fuel my cars get.

[Tommy]

IMHO, additives are as unlikely to cause a problem as they are to fix one. I'd look elsewhere for the cause of his symptoms. .... As was said above, its very rare to find an octane booster you can buy in a small can at a normal retailer that actually does anything. .... And how does he know what an engine with diluted gas sounds like? I don't.

[1795]

Sounds to me like your friend might be miss-associating the additives with the poor performance and is not considering another probable culprit, bad gas (i.e., water in the gas). It is common for underground storage tanks to have some water in them and it typically is not a problem, unless the tank has been freshly filled and the agitation of the new gas coming in mixes the water with the gas. Your friend may have filed up at the wrong time. I do agree with Tim in that a person should probably not be filling up with regular gas in one of these cars; premium would be the gas of choice at the pump.

Being that he burned off 1/4 of a tank and then added fresh gas and saw somewhat of an improvement, suggests there might be water in the gas. I have had this happen before in another car and added a water treatment and kept topping off the tank with fresh gas until the situation went away.

[BAsque1]

Tks guys my buddy ended up draining the bad fuel out and replaced with good fuel, all is well now.
Tks all for your input.
Regards
Happy Thanksgiving
Lou, II

[Tommy]

Lou,
Thanks for wrapping up the thread. ...... A random thought popped into my head. I wonder what would happen if someone topped off a half tank of gasoline with E85. It costs a lot less than regular gas, and many people don't understand the differences in gasoline types. Hmmmmmmm?

[RICK LAKE]

BAsque 1 Lou There is info on the bottles about not mixing and ONLY using every 3K miles. The other big problem is if he is running rubber fuel lines, both else ADDITIVES WILL EAT THE RUBBER. Over time the outer rubber will dry and harden in the gas tank. It cracks. The inner rubber of the hose is eaten away over time. With a higher pressure system like FI took about 8years. Always kept a 1/2 tank of fuel in it. The hose was always wet or in gas vapors. I have a fuel filter that has a replacement inner filter and found black partials that looked like little balls in it. The short lines from the pumps to the fuel module came apart. Methonal in the fuel doesn't help either. This is th reason 95% of the fuel systems run plastic and not rubber any more. SS line come in different materials. Some have a plastic inner and some of a rubber inner. Mine gave out the last time at R&G in Okla. The diapham in my fuel pressure regulator also died and cracked.
If you figure out the cost of booster against running high test, it is about even money. As for fuel cleaning additives, If you run a good fuel filter with a 3-10 micron filter, you will not have any dirt or partials that will effect the system. Adding fuel stablizer to the tank is important. The other thing I do with a carb is remove and drain it completely for winter storage. In the spring add fuel and fire up. I have drains on both ends on my injector rails and drain them. The rest of the system is full with stablizer. Have no problems with this way and the car sitting 5 months in the trailer. Same for the boat. Good luck Rick L. Ps Happy holidays too

[RICK LAKE]

Tommy E85 is a higher octane but needs more compression to make the same power. You can run 14.5 compression with E85 and no problems but need this to get the power back to wear you where running 100 octane gas and 12.0 compression in the motor. It does burn cleaner, It's alcohol. It runs cooler, needs more compression, and cheaper if the motor is setup that way. No sure about how the camshaft setup would help or hurt a motor. I do know we have people here in nj that run E85 and there is a 15% loss of power running this fuel with the Bi fuel setup. This is GM. I don't know about Ford or Dodge. Rick L.

[vector1]

I'd not think the two additives in themselves would do any harm. Foam filled tank or maybe rubber parts coming loose.

[Tommy]

I understand Rick. I was wondering what would happen if you tried to run an engine designed for 90/10 gas on a 50/50 gas/alcohol mixture. I assume it would run (or not) noticeably different.

[RICK LAKE]

Tommy I am going old school but would think you would be running a 12.0 AF ratio on the motor. A safe motor would be like running alcohol. You would really have the watch the timing. Want a good long spark in each cylinder for complete burn. If it was my motor would want surfaces coated like pistons and heads of the combustion chamber with Swain coating. R&G we had Randy S come to the race and race propane in the car. It made stupid power. The car was setup for pikes peak. The compression on the motor was like 16.0-1.
If you are serious at running 50/50, I would get info and look into a alcohol carb to run this. I due know from the customers that own Bi-fuel truck and run both, it's a wash. They loss 2-5 mpg with e-85. This is a full size Yukon with a 5.3 motor. Looking at about 5,400 pound without extras. It's like gas and diesel towwing. My SBC in my dually gets 10-12 mpg towing. I hear diesel guys say they get 16-18 towing with same size trailer. Max speed for me is 65-68 mph on flat. I hear alot of guys getting more like 12-14 mpg. Bottom line, it's like FI systems, find the right guy who know how to get max power and keep the motor alive when racing and you are gold. Wrong setup and you are looking at big bucks for repairs. IF you have a couple of motors, try it. If only one good bullet, I would skip this idea for now and run race fuel. Buy custom is really needed. Rick L.

[WardL]

I'm pretty sure all racing gas has more than 10% ethanol. My Flex-Fuel F-150 is made to run fuel with ethanol anywhere between 85% to zero. If you buy E85 with a half tank of E10 your tank will be about 50% Ethanol. The specs show it actually gets more HP with the E85 because the computer can adjust for the higher octane. The issues with running E85 is the parts that touch the fuel have to be made to handle ethanol. I think the flex-fuel vehicles have mostly steel fuel systems. Any rubber is special to handle the high ethanol. Another point of interest, they call it E85. But the ethanol can legally range from about 50% to a max of 85% depending on the season. I suggest to stick with premium gasoline for your Cobra....