89 octane gas in supercharged taco

Hey,

I have a supercharged Taco and the fuel door says to use premium fuel only. Just curious, what would happen if I used 89 octane? premium fuel is getting expensive here! =(

Thanks.

 

Engine knock.

Don't want to pay for premium? I pay shipping for your Supercharger then you can throw 89 in there all day long.

 

you took the words right out of my mouth...

send me the s/c...i'll give you $1.01 more then he will...lol

 

Respect your elders sonny.

Or I'll break my hip on your face.

 

i have run them all, i see no reason why, i run 89 in mine every tank, i have run 87 to with a bottle of lucas, no problems here

 

i run 91 with no sc it helps the truck and it will last longer!

 

X2

 

thats an old "wise" mans tale...

 

You get what you pay for i get better gas mileage when i run 91!

 

Here 91 just dropped back to $2.79 from $3.15! I have to run Premium in three of my vehicles so I know the pain of paying for 91.

In reality the .20 more per gallon on a 21 gallon fill up is only $4.20. If you burn through a tank a week, is it worth a few bucks to possibly damage your engine? Have one less Caramel Frapachino half-caf, mocha swirl a week and save your engine!

 

now thats fucking funny!!

 

I run 91 octane in my supercharged taco, do it. Just do it.

 

yea it says premium only for a reason.. you get engine knock, you lose performance and get worse gas mileage..

 

This is one of those "pay to play" things- It's really not a good idea to test out if 89 will work.
It might be just fine for a while- Find the right combination of weather and gas- and you might be paying for an engine rebuild...Just that fast.

@ 2-3 bucks more a tank (max)- You'd have to fill up about 1000 times or more before you'd save enuf money to pay for an engine rebuild....

 

really...helps the truck and make it last longer huh...do you even know what the octane readings mean?!!

there is absolutely no reason to run anything more than 87 in our NA trucks. forced induction trucks need the higher octane to prevent knock (ie. predetonation).

as as to your "better mileage" theory, there is no change in the energy content between 87 and 91 octane fuel...its simply a measure of the fuels tendency to burn in a controlled manor.

in conclusion, OP, as others have stated, your running the higher octane fuel to control the burn in the cylinders and not knock...this will extend the life of your engine when you run the SC...

 

Regular (87 octane rating) fuel is fine (IMHO) in stock Toyota engines.
However;
To prevent uncontrolled detonation (pre-ignition), higher octane ratings are required whenever you increase cylinder pressure, whether it's via supercharging, turbocharging, higher compression pistons, reducing head deck height, etc...
I believe the matter of "octane" requirements & the associated reasons have been discussed extensively in previous threads.
Do a search for "octane"..

 

the trd website claims you can run lower than 91 octane in a supercharged application, but "performance will be reduced" also as a side note, the VVT-i system in our trucks DOES perform better with higher octane fuels ( not just better gas mileage, but better performace) but you can run any octane in a NA engine (ive had both...)

 

Do you really get better gas mileage or are your driving habits a little different when running different fuels?

I filled up yesterday with 87octane for 2.65 a gallon for a total of 45.05.
For 91octane it would have cost 50.15 to fill up. Would 10 more miles a tank make up that 5 bucks? I fill up once a week usually and that would be an extra 20 bucks a month...I just dont really know if it would be worth it

 

I am sorry, but I disagree with this statement.
Simply put, VVT (Variable Valve Timing) systems are meant to increase efficiency in engines via managing 'pumping losses' while maintaining 'normal' engine performance values, not to increase performance.
This is done by decreasing 'cylinder pressure' (ie-shortening the compression cycle) via 'valve open' durations during periods of low load (where most vehicles are normally operated) & returning to the 'normal valve duration cycle' of an engine, when under load.
The trade-off for the 'efficiency state' of VVT is a loss of engine torque, as that is what occurs with reduced cylinder pressures. However, this operation is managed electronically & happens so quickly that any torque loss is 'transparent' to the vehicle operator.
The only performance gains that VVT technology provides is that the Manufacterers did not have to completely dog down engines to meet Government C.A.F.E standards for efficiency for the vehicles they sell.

As I have stated previously, the only time you would REQUIRE premium fuel is when you INCREASE cylinder pressure one way or another (supercharger, turbocharger, high compression pistons, etc...)

 

The only benight of higher octane in an application without boost or a high compression ratio is potentially higher grade fuels have more additives. Other than this, premium fuel is LESS VOLITAL than regular fuel, and also generally has a lower energy content than regular fuel, due in part to higher octane is generally created by mixing more ethanol into the fuel. In high performance engines that run the risk of pre detonation the advantage is that you can a higher degree of spark advance to make a bit more power. Converaly, modern car with a nock sensor will retard timing when it notices knocking occuring. Your consumer brains are progred to think 93>89 which =better. This is not true, it is a question of what makes sense in what application. If you are putting premium gas in a stock Tacoma in hopes that your truck will last 10k more, you are straight up pissing away $10 into the petroleum machine every time you fill up. Over the life of the truck you will spend more doing that that the cost of a new truck.