87 or 93 octane gas??? what do you prefer?
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From: bayamon, pr
87 or 93 octane gas??? what do you prefer?
just wanted to get your thoughts on it. the book says 87 so i put 87. we have 93 here. what would you prefer in your truck and why? mine is a 2006 3.0 what would be the "better" gas?
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From: Jacksonville NC
You should always run the lowest octane gas you can without detonation, it will produce the most power this way.
Higher octane gas is a slower less volatile burn and more controlled so when run in a lower compression engine with a less agressive timing curve, it actually produces less power.
The only reason some people have to run a higher octane on a high mileage vehicle is because the deposits on the valves and combustion chamber actually lower the overall area in the chamber increasing compression by default and create more heat requiring the 89/91/93 to resist detonation. A simple can of Seafoam engine cleaner from AutoZone sucked through your brake booster hose will clean that out though and you can go back to the cheap stuff just fine.
Higher octane gas is a slower less volatile burn and more controlled so when run in a lower compression engine with a less agressive timing curve, it actually produces less power.
The only reason some people have to run a higher octane on a high mileage vehicle is because the deposits on the valves and combustion chamber actually lower the overall area in the chamber increasing compression by default and create more heat requiring the 89/91/93 to resist detonation. A simple can of Seafoam engine cleaner from AutoZone sucked through your brake booster hose will clean that out though and you can go back to the cheap stuff just fine.
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Joined: Nov 2005
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From: Charlestown, IN
Originally Posted by slodsm
A simple can of Seafoam engine cleaner from AutoZone sucked through your brake booster hose will clean that out though and you can go back to the cheap stuff just fine.
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Joined: Jun 2004
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From: Kennett Square, PA
If your 3.0 engine is vin code "V" ("flex-fuel") rather than "U", there may be some benefit from running higher octane gas since the timing advance limits appear to be wider on those models.
But for a vin code "U" (non-flex-fuel) I wouldn't go over 89. The reason is that high octane gas burns more slowly, albeit more powerfully, and if you put high octane in and do not advance the timing you may still be combusting when the exhaust valve opens. This is bad for a couple of reasons, not the least of which is that the "quenching" of the flame causes incomplete combustion and carbon buildup.
But for a vin code "U" (non-flex-fuel) I wouldn't go over 89. The reason is that high octane gas burns more slowly, albeit more powerfully, and if you put high octane in and do not advance the timing you may still be combusting when the exhaust valve opens. This is bad for a couple of reasons, not the least of which is that the "quenching" of the flame causes incomplete combustion and carbon buildup.
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From: Jacksonville NC
Originally Posted by lifted97ranger
are you serious?
That stuff is the bomb man, but it isn't some fly by night "engine restore" crap, if you use it on a weak motor, it will get worse because on some, carbon is all that is keeping the valvetrain sealing.
The way I have always used it is 1/3 in the gas tank, 1/3 in the oil (do this shortly before changing the oil, say a day or two at most to clean out oil passages a bit) and the last third takes two people. Have a buddy in the car hold the RPM's to about 2k because you are about to make a serious vacuum leak. Pop off the brake booster vacuum line and throw it in the remainder of the can. The car is going to suck it all out drawing it through your intake and cleaning valves and combustion chamber while doing so. It will smoke like you have never seen while doing it, you won't have mosquitoes for a month or so lol. Once it's all sucked out, throw the booster line back on and let it smoke. After about 5 minutes take it out for a drive. It is going to blow massive amounts of smoke for about 5 miles or so and then clear up like nothing happened and that is it man.
Once you do this, it's done and over with BUT, if the motor is worn out and the rings or valve seats are beat up, it will be worse because of the new found cleanliness of it. If it's a healthy motor, it will make it clean again, if it's not, it will be dead lol.
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Joined: Nov 2005
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From: Charlestown, IN
Originally Posted by slodsm
Very :)
That stuff is the bomb man, but it isn't some fly by night "engine restore" crap, if you use it on a weak motor, it will get worse because on some, carbon is all that is keeping the valvetrain sealing.
The way I have always used it is 1/3 in the gas tank, 1/3 in the oil (do this shortly before changing the oil, say a day or two at most to clean out oil passages a bit) and the last third takes two people. Have a buddy in the car hold the RPM's to about 2k because you are about to make a serious vacuum leak. Pop off the brake booster vacuum line and throw it in the remainder of the can. The car is going to suck it all out drawing it through your intake and cleaning valves and combustion chamber while doing so. It will smoke like you have never seen while doing it, you won't have mosquitoes for a month or so lol. Once it's all sucked out, throw the booster line back on and let it smoke. After about 5 minutes take it out for a drive. It is going to blow massive amounts of smoke for about 5 miles or so and then clear up like nothing happened and that is it man.
Once you do this, it's done and over with BUT, if the motor is worn out and the rings or valve seats are beat up, it will be worse because of the new found cleanliness of it. If it's a healthy motor, it will make it clean again, if it's not, it will be dead lol.
That stuff is the bomb man, but it isn't some fly by night "engine restore" crap, if you use it on a weak motor, it will get worse because on some, carbon is all that is keeping the valvetrain sealing.
The way I have always used it is 1/3 in the gas tank, 1/3 in the oil (do this shortly before changing the oil, say a day or two at most to clean out oil passages a bit) and the last third takes two people. Have a buddy in the car hold the RPM's to about 2k because you are about to make a serious vacuum leak. Pop off the brake booster vacuum line and throw it in the remainder of the can. The car is going to suck it all out drawing it through your intake and cleaning valves and combustion chamber while doing so. It will smoke like you have never seen while doing it, you won't have mosquitoes for a month or so lol. Once it's all sucked out, throw the booster line back on and let it smoke. After about 5 minutes take it out for a drive. It is going to blow massive amounts of smoke for about 5 miles or so and then clear up like nothing happened and that is it man.
Once you do this, it's done and over with BUT, if the motor is worn out and the rings or valve seats are beat up, it will be worse because of the new found cleanliness of it. If it's a healthy motor, it will make it clean again, if it's not, it will be dead lol.
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Joined: May 2005
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From: Livonia, Mi
try the seafoam but dont put it in the oil...
run half in the brake booster and the other half with a half tank of gas.
chances are if you run it in the oil your going to get seal leaks and plug up your pickup tube.. bad idea..
run half in the brake booster and the other half with a half tank of gas.
chances are if you run it in the oil your going to get seal leaks and plug up your pickup tube.. bad idea..
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Joined: Jul 2006
Posts: 291
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From: Jacksonville NC
Originally Posted by 5speedin2.3
try the seafoam but dont put it in the oil...
run half in the brake booster and the other half with a half tank of gas.
chances are if you run it in the oil your going to get seal leaks and plug up your pickup tube.. bad idea..
run half in the brake booster and the other half with a half tank of gas.
chances are if you run it in the oil your going to get seal leaks and plug up your pickup tube.. bad idea..
Lifted97, last time I used it, it was in a 130k motor that had eaten about 400lbs of nitrous in it's life and I had no problems as the motor was taken care of and regular maintenance had always been performed. I used it because of a crappy idle when all the electronics were functioning properly. I am sure it had been beaten and abused a lot more than you Ranger so I wouldn't be concerned. Sludgy ill maintained motors are the ones it will let down.
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Originally Posted by slodsm
And you are basing this opinion off of what? Seafoam doesn't harm seals whatsoever. It does ever so slightly dilute the oil hence why I stated CHANGE YOUR OIL SHORTLY AFTER. If you have only an opinion and no fact, please don't dilute the thread with information that can't help anything, it only furthers the damage to a good product and starts another internet rumor that will spread like a cali wildfire and within 2 months, Seafoam will be out of business because everyone now thinks it destroys motors.
what does the directions on the can say?
