93, 89, and 87 octane tested towing / driving

[Vinny Singh]

Just went on a 700+ mile trip with the Titan, and have some interesting information (maybe it's interesting)

The truck, if you aren't hauling anything, can run perfectly fine with 87 octane. If you hauled a 4400lb+ car/trailer, up and down some mild hilly tollways, you probably want to use 89 or 91+ octane. On the trip there, the truck had 89 in it, and felt good while towing. I filled up with 92 or 93 half way there, and noticed almost no difference.

However, on the trip back, we were running out of money for the weekend, so I put in 87, and the truck lost power in the upper rpm bands, and felt sluggish all around whenever there was any incline.

I highly recommend you up the octane if you are towing anything, otherwise, you are just knocking, and the ECU will pull timing to keep it happy. With 87, we also seemed to lose mpg, but it was only one tank and one trip back, so not very scientific.

On another interesting note, the fuel guage doesn't seem linear, it drops fast for the first 1/4 to 1/2 tank, then takes a while to go down, getting even slower around 1/8th.

We were towing a twin engine 91 talon for it's maiden 1/4 mile runs in Norwalk Ohio this weekened, it did very well (12.3 @ 114mph at about 60-70% throttle, not applied for full run). It was running 112 octane, and 18lbs of boost in each engine, and all it was hauling was *** . It's still not tuned right, its running pig rich in any mid or high throttle settings, but still has a little knock from the rear engine. Any other engine tuners out here?

keywords : Towing octane rating knock ping knocking detonation mpg timing sluggish load weight manual 87 ron aki mon 89 91 92 93 race gas lead leaded cat catalytic o2 sensor fuel gasoline petrol

[rrumaner]

This has been discussed over and over and based on the manual, putting anything other than 87 in the tank could cause engine damage. The compter is programmed for a certain octane and is what controls the firing of the plugs. You are potentially causing problems by not following the manufacturers recommended ratings.

With the cost of gas these days, the only thing I am putting in my tank is the lowest priced gas I can find and that means 87 octane which is around $1.85 today.

[LuvMyTitan]

Originally Posted by rrumaner

This has been discussed over and over and based on the manual, putting anything other than 87 in the tank could cause engine damage. The compter is programmed for a certain octane and is what controls the firing of the plugs. You are potentially causing problems by not following the manufacturers recommended ratings.

With the cost of gas these days, the only thing I am putting in my tank is the lowest priced gas I can find and that means 87 octane which is around $1.85 today.

O.K. This goes against anything I've ever known about octane and engines. In the past, it was always lower octane that had potential for causing engine damage because of detonation. I had always understood that if you put in a higher octane gas, it couldn't hurt, other than the fact that it could be a waste of money. On what basis do you state that a higher octane could cause engine damage?

[SWEED32]

Originally Posted by LuvMyTitan

O.K. This goes against anything I've ever known about octane and engines. In the past, it was always lower octane that had potential for causing engine damage because of detonation. I had always understood that if you put in a higher octane gas, it couldn't hurt, other than the fact that it could be a waste of money. On what basis do you state that a higher octane could cause engine damage?

Yeah I would agree... How would Higher octane hurt it...

[Rob Sanders]

Running 91 instead of 87 isnt going to ruin a motor.

The higher the octane the slower it burns( helps fight detonation which is what ruins motors)...

You will see absolutely ZERO performance gains from going to one or the other UNLESS you are detonating and need the higher octane to get rid of it.

Im running 87 in 120* weather with no detonation issues. Running 91 would be pissing my money away.

[SWEED32]

Where are you that its 120 ?

[TriKKy]

Christ, I cant believe this is even discussed anymore.

There are 1 million differing opinions on this. I don't agree that in the case of the Titan, higher octane hurts, the question about "helps" isn't going to be really settled until somone does some dyno-ing. I've been under the impression that the Titan can advance its timing, that being the case, it doesn't matter what you put in it, it will not do damage.

My guess is that the Titan was mapped on 89 or 91 gas. Given the initial "premium fuel required" that showed up in the manuals or ads or whatever.

Either way, search, and you will get the 1 million arguments on octane.

Until I see dyno results, most things people say are speculation about the Titan in particular.

My service manager told me to put premium in it since it will save the O2 sensors in the long run blah blah blah blah more blah blah blah and then you just nod and do what you want to do.

[sasilverbullet]

trikky - nice dog! While I understand your frustration, don't give up! The facts ARE out there, somewhere...

Some facts I DO know:
1. A car computer can adjust the timing, been doing that for years.
2. I just saved money on my car insurance by switching to...never mind...

[Rob Sanders]

Originally Posted by SWEED32

Where are you that its 120 ?

Vegas...I rounded up.

[Truck41]

let me shed a little light on this subject, first of all, high octane will not harm your engine. yes the titan is designed to run well on 87 oct, what you guys don't know, is that the ecu will automatically adjust to a higher octane fuel. for the first time, i put in half a tank of premium, yes it does run stronger. if you don't believe it, try it.

[Vinny Singh]

Like I said, the Titan has a knock sensor, and in closed loop mode (probably under a certain throttle position), it's adjusting timing to give you the best possible performance and economy.

Under a lightly loaded truck, I stated that 87 octane seems to be fine, but you add nearly 5000lbs, and start straining the motor, pullling it up hills and doing 75+mph (and passing slow people), it feels sluggish and tentatively seems to eat more gas with 87.

I switched to 89 and 92 or 93 just to see if there were any differences, and there was, but ONLY under a heavy load. Some people drive less or more aggressively, so this information my not pertain to you, and you may not notice it. If an ls1 needs a minimum of 91 octane, and makes about the same power with the similar displacement, and both have computers fully capable of using the higher octane to your advantage (when towing in this case), why would the it be that different? It only costs around 5-10% more to fill up.

You think Nissan wants to scare people away from their cars by blatantly stating to use 89+ at a time like this when gas prices keep going up? Nah, I think they will stay quiet, and let you figure out on your own what might be best. Infinti states premium fuel for the qx56 (when you pay 50k+ for a car, you probably don't have to care). it's VK56 is probably mapped a little differently due to the 10 less hp that the titan/armada is rated at, but what I observed in a real life test is entirely plausible.

How would one dyno a titan with a decent load on it? I'm just stating what I observed, didn't anticipate arguing about it. Thought maybe it might help someone.

"Christ, I cant believe this is even discussed anymore."

I just got here.

Your service manager might be right about the o2 sensors, less retarded timing, less soot in your exhaust (more efficient burn), less EGT's, less crap coating things that should stay clean.

[MadCow Titan]

Im going to ask a friend that is a Tech in Canton what the factory recommendation on octane is now that the titan has been out a year - I will report back to you dudes.
Also, Vinny - are you kin to VJ thats on the PGA Tour????

[LuvMyTitan]

Originally Posted by MadCow Titan

Im going to ask a friend that is a Tech in Canton what the factory recommendation on octane is now that the titan has been out a year - I will report back to you dudes.
Also, Vinny - are you kin to VJ thats on the PGA Tour????

If you are a kin, telly Vijay congrats from us on a fine playoff win!

[Titan Power]

Hi Vinny, I thought I recongnized your name. I've been a DSMer for years, I remember you back from the Talon Digest! I've seen pics of your twin engine Talon, awesome work. I can't wait to hear what it runs after you get it all dialed in.

As for octane and the Titan, I've been saying the same thing. Light load, normal driving, 87 is just fine. You should get more power with 91+, but it's debateable how noticeable it would be without a stopwatch or heavy trailer behind you. 10-15 extra hp on a 300+hp, 5000lb. truck won't be too noticeable. But it's still there. I do feel that the Titan is tuned very conservatively, and that there is a quite a bit of power to be unlocked.

Jason K.
'90 Eagle Talon AWD R.I.P.
'92 Mitsubishi Galant VR4
'93 Eagle Talon AWD
'96 Mitsubishi Eclipse GSX
'04 Nissan Titan SE

[rrumaner]

I stand (actually I am sitting) corrected on my statement that higher octane would hurt the engine. I was trying to remember the information that I have read in this forum over and over (and over and over) again and got that one wrong.