can I use regular gas or do it have to be premium,my salesman said to use premium with gas so expensive I was just wondering

Manual says regular.

Regular = 305 hp
Premium = 315 hp
The computer advances the timing based on feedback from a knock sensor. This gives you 10 hp with super.

oh geez.......... ;)

Ha! I am busting up.

Ha! I am busting up. Gotta love it. :D
;)

So which gas are you using?

315 on super... So is that why the QX is rated at 315 and requires super (premium, hi-tes: dependent on what part of the country you are from.) Don't tell me that there really aren't any mods, just different gas. OMG (just another image enhancer). MMMYYYY truck runs on "premium" unleaded, what about yoouuurrrrsss. HAHA, just regular... (all said with a snooty sound looking down over their nose at you). PLEASE TELL ME THERE IS MORE TO IT THAN THAT! :nana:

Just in case anyone is wondering, there was another thread that got shutdown recently about gas octane. Go check it out. It was a lively discussion but I think it does bring up a lot of good points and some insight into if the QX56 and Armada engines are the same or different. And why the hp ratings are different.

315 on super... So is that why the QX is rated at 315 and requires super (premium, hi-tes: dependent on what part of the country you are from.) Don't tell me that there really aren't any mods, just different gas. OMG (just another image enhancer). MMMYYYY truck runs on "premium" unleaded, what about yoouuurrrrsss. HAHA, just regular... (all said with a snooty sound looking down over their nose at you). PLEASE TELL ME THERE IS MORE TO IT THAN THAT! :nana:
Nope. Its a marketing ploy to allow Infiniti to advertise a higher HP rating. Same exact motor, ECU, etc. and made on the same assembly line. :teeth:

You're right, gas is expensive, especially when your only getting 14 mpg, LOL

But, I have to believe that the motor will run a little better on premium...and that's what I've been using for the first 4 tanks.... I would love to switch to regular unleaded but for a few more cents (or dollars with 30gal tank) :) I will stick to the premium.

For what its worth, all of the service advisors at my nissan dealar insisted upon using premium only..

I get knocking on hot days with 87 octane.(not sure why?) So I usually use 89 or 91.
The higher the altitude, the lower the octane you need.
If you live at 3,000 ft and up, 87 should be fine.

Exact same displacement, bore, stroke, valves per cylinder, and compression ratio. Could it just be the premium gas and subtle timing change? Hmmm, suspicious!

http://www.internetautoguide.com/car-specifications/09-int/2005/infiniti/qx56/

Nope. Its a marketing ploy to allow Infiniti to advertise a higher HP rating. Same exact motor, ECU, etc. and made on the same assembly line. :teeth:

No difference. None. And the Infiniti does not have to run premium. Put 87 octane in it and it runs just like ours, smooth, strong, but "just" 305 horses.

BTW, to get the extra horses, even with premium, you have to be at wide open throttle or heavy load conditions that would call on the engine to continue to advance timing enough to benefit. That means unless you are going to the drag strip or towing a trailer up a steep grade you probably will never see those extra horses. But your pocket book will feel them on every single gallon.

But if you want to say you have 315 under your right foot, 93 octane will get it for you.

I think I've been here before?

Bueller, Bueller, Bueller.
Correct. The timing is adjusted by the ECU based on what the knock sensor is telling it. It can advance the timing more with higher octane before you have detonation and knock problems, therefore it gains the extra power. They tested the qx56 motor on super, and armada/titan on regular. Same applies for the g35 motor. Even says in the manual you can use regular but for max performance use super. Cool new generation of ECUs we have here. They even control the shift points on the G with the computer based on driving habits for either max performance or economy. I think this is the same for our vehicles. :amazing:

So the net result is:
If you want to save money you can use regular or plus. If you want max power, you can go to premium. Your choice, but any will work and not be a waste of money. ;)

Hope this clears it up.

either way, im willing to bet you wont be able to tell a difference in HP numbers with a "seat of the pants" dyno .......

also..at the drag strip and during towing, torque is what counts, not HP

either way, im willing to bet you wont be able to tell a difference in HP numbers with a "seat of the pants" dyno .......

also..at the drag strip and during towing, torque is what counts, not HP
As a Bud drinker would say, "True!" This is another reason to get a Supercharger. :teeth:

Torque only gets you going,Horsepower finishes off your run at the drag strip.

no......hp means you can go faster... torque is what is pushing your *** into your seat the whole 1/4 mile ....

Why do you make a reference to HP at a drag strip not being a factor than in your next quote you say it makes you go faster.Can you please explain?

umm so is it ok then to fill up one tank with 7 then the next one with 93 and then on and on and on?? since 93 is only if u want ur engine to perform at its best"... will the changing of octanes damage the engine at one point?

Why do you make a reference to HP at a drag strip not being a factor than in your next quote you say it makes you go faster.Can you please explain?


hp is the ability to go/obtain certain speeds ..... torque is how fast you get there .... if you have a 1000 hp car with 200 lb ft of torque, its not gonna go anywhere very fast, but has the ability to eventually get going a high rate of speed ....... if you have a 100 hp truck with 1000lb ft of torque, you can pull a house, but you wont be able to get up to a decent speed

umm so is it ok then to fill up one tank with 7 then the next one with 93 and then on and on and on?? since 93 is only if u want ur engine to perform at its best"... will the changing of octanes damage the engine at one point?


no, it wont damage the engine...the engine itself doesnt know the difference

umm so is it ok then to fill up one tank with 7 then the next one with 93 and then on and on and on?? since 93 is only if u want ur engine to perform at its best"... will the changing of octanes damage the engine at one point?
He's right. No damage. Your knock sensor will tell the ECU what's up and it will adjust accordingly.

He's right about HP and TQ. HP is a function of TQ and RPM. TQ is how hard the motor pulls/pushes. A good TQ curve is one that has high TQ throughout the RPM range. As RPM increases, TQ usually decreases. But the ratio of TQ and RPM can get you higher HP numbers.
To calculate HP, you multiply TQ and RPM and then divide by 5252. So if you have a very high RPM motor with so so TQ, you can have higher HP numbers than a high TQ motor that doesn't go high into the RPMs.
Bottomline, this translates into TQ=acceleration and HP=top end speed and is why 300 hp in my corvette makes it so much faster than similar HP my G35.
The Vette has a high TQ curve for a long RPM range. Remember, TQ and HP are rated at peak numbers. If they have a spike at a particular spot in the curve, they can be misleading. GM SUV/Trucks have this spike and their numbers seem high for the amount of kick you get from them as a result.
Its also why I continue to say HP rice rockets suck next to high TQ V8 pony cars for speed. They have the HP from the high RPMs and not TQ so the acceleration isn't as strong.
Hope this helps. ;)

either way, im willing to bet you wont be able to tell a difference in HP numbers with a "seat of the pants" dyno .......

also..at the drag strip and during towing, torque is what counts, not HP


Your original quote said horsepower does not count at the drag strip.It does.If your armada has 305 hp and mine has 315hp who will get to the finish line first.(Assume all other conditions are the same,that is,weight,launch,gearing,etc.)As you can see it does matter at the drag strip.Unless the laws of physics don't apply there.

Your original quote said horsepower does not count at the drag strip.It does.If your armada has 305 hp and mine has 315hp who will get to the finish line first.(Assume all other conditions are the same,that is,weight,launch,gearing,etc.)As you can see it does matter at the drag strip.Unless the laws of physics don't apply there.
Not necessarily. EX: the late 70s trans am had a 400 motor that made tons of tq but had lower hp than the same bodied camaro. The Trans Am won the quarter mile times, the Camaro top speed. The Trans, with the same body, etc. and less horsepower won on race day. HP matters, but TQ matters more for acceleration. ;)
I picked 1978 because I love Smokey and the Bandit. :teeth:

1978 Trans Am 400CI 180 HP, 325 TQ, 15.2 quarter mile, 0-60 7.1, top end 123 mph.

1978 Camaro 350 185 HP, 280 TQ 16.0 quarter mile, 0-60 7.3, top end 123 mph.

More HP, less TQ=less acceleration.

Now see if the 315 HP is created because of a spike at the end of the powerband or if you have slightly more TQ across the powerband. In the first case, you probably lost TQ in one spot and gained it elsewhere. This often happens on large muffler installations on rice rockets. Put a big pipe on one, it lowers back pressure, you loose TQ but gain HP. Result, slower acceleration.
You'd have to compare the TQ and HP curves of the two setups to see what would be faster at the track.

Sorry, but he's right. ;)

The original quote states horsepower does not apply at a drag strip.The last time I was at a drag strip the person who got to the finish line first won.So since we are comparing two identical vehicles(not a trans am and camaro) with a 10 hp difference I think it is safe to say the vehicle with more hp wins.This is all stemming from adding a higher octane to achieve more hp which you may only see at a race track.So no he's wrong.

The original quote states horsepower does not apply at a drag strip.The last time I was at a drag strip the person who got to the finish line first won.So since we are comparing two identical vehicles(not a trans am and camaro) with a 10 hp difference I think it is safe to say the vehicle with more hp wins.This is all stemming from adding a higher octane to achieve more hp which you may only see at a race track.So no he's wrong.
Guess you weren't paying attention or reading closely.

I'll put it in other terms.
Put a fart pipe on a Honda Civic and it gains more HP and looses TQ due to the loss of backpressure. A Stock Honda Civic without the Fart pipe will win the race because it has more TQ but the fart pipe will have a slightly higher top end speed.

The only way to see if an Armada with 305 HP is faster in the quarter than one with 315 HP is to race them or see the TQ curves. The 305 may have more Torque for a longer stretch in the Torque curve than the 315, which may have a little more in the high end of the RPM band, but less in the lower and middle RPMs.

When you advance timing and gain HP, you can loose lowerend Torque. This is what motors do. All things being equal, the 305 regular gas may outperform the 315 premium in the quarter.

I don't know if this is the result or not, but higher HP is not enough data to go on to say it would win the race. ;)

BTW, you do gain 6 TQ with premium, but again, I don't know if you gain TQ over a majority of the power band or just a small spot up top, loosing it in the low and mid RPM ranges. If I had to bet, I would think the 315 would be a hair faster, but without the data, I wouldn't bet a nut on it. :moon:

BTW, I picked the T/A and Camaro because they were basically mechanical clones of each other except for engine and front end grills. One had a motor that was a TQ monster, the other a motor that was a HP monster. :191:

So what is the advantage of adding premium fuel and gaining 10 hp?Why not stick with lower octane?I personally will only run high octane but you've just stated in the beginnning of the thread you should see a 10 hp increase.If the Armada will run slower with higher octane why bother?

So what is the advantage of adding premium fuel and gaining 10 hp?Why not stick with lower octane?I personally will only run high octane but you've just stated in the beginnning of the thread you should see a 10 hp increase.If the Armada will run slower with higher octane why bother?
That's the question. I don't know if there is an advantage. I think in the end we would get a couple TQ and HP, but nothing you'd notice and maybe a tenth or two on the quarter, if we're lucky. I'm researching it now trying to find a comparison dyno. ;)

Thanks for the info.,please let us know what you find.

Let's not forget that normal factory assembly variations can account for 5% swings up or down in motor output.
I used to have a Mustang 5.0 that was exactly the same as a friend's except for color. His always pulled harder, and it sucked.

...
BTW, I picked the T/A and Camaro because they were basically mechanical clones of each other except for engine and front end grills. One had a motor that was a TQ monster, the other a motor that was a HP monster. :191:
Just curious, how about gear ratios and final drive? Sometimes they would fiddle around with those between brands.

Just curious, how about gear ratios and final drive? Sometimes they would fiddle around with those between brands.

same for the Armada and Q56

I was thinking more between the old Camaro and Flaming Chicken, err, Firebird.

Just curious, how about gear ratios and final drive? Sometimes they would fiddle around with those between brands.
I choose times with cars that had the same ratios/trans in them. This was a factor for chosing I considered.
The QX56 and Armada have the same trans and rears and gearing in them. All the times are using the lower gearing of the big tow pkg to maximize acceleration. The QX56 has the "big tow" option for Armada as part of the package and is standard equipment. If you have other gears, you will be slower. 2wd vs. 4wd will also affect acceleration as 4wd has more friction and weight. :rolleyes: