what octane should KA use 87 or 89?
03-13-2005, 10:40 PM
#16
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Join Date: Nov 2004
Location: Long Island,NY
Posts: 380
Originally posted by Ghettostamps
This is correct, higher octance will not hurt your engine, lower octane can, lower octance detonates at a lower compression and if the octance cannot handle the compression, then it will detonate before it is ignited meaning that the gas is compressed too much, hence detonation.
This is correct, higher octance will not hurt your engine, lower octane can, lower octance detonates at a lower compression and if the octance cannot handle the compression, then it will detonate before it is ignited meaning that the gas is compressed too much, hence detonation.
I agree with you but some ppl have had different experiences. I've heard that some motors just don't like higher octane. I use 93 myself. I'm just sayin I've heard the same crap that smokie700 has heard. I'll try to find out what motors in specific. It wasn't Nissan.
03-13-2005, 10:51 PM
#17
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Join Date: Mar 2005
Location: Boston/New York
Posts: 140
Ok, you may be right, I'm not saying I know everything under the sun when it comes to motors but its pretty much physics, the octane can only withstand a certain compression ratio. If your right, I'd like to know what dynamic it is that makes higher octane unstable.
03-14-2005, 02:20 AM
#19
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Join Date: Feb 2004
Location: Ewa Beach, Hawaii
Posts: 778
well i have a ford explorer and a nissan. My mom works for ford for 20 sunphin years. (sservice manager and district rep) I know that fords are better to run at the octane prescribed for a stock motor. I just apply that theroy to any other stock engines. Engineers are engineers for a reason. hehe
Now the rational person in me agrees that higher octane will only gain you .00009% more horsepower but if you have the money then spend it. Now im ddrunk and will revert to my drizunk post.hehe
Now the rational person in me agrees that higher octane will only gain you .00009% more horsepower but if you have the money then spend it. Now im ddrunk and will revert to my drizunk post.hehe
03-14-2005, 04:12 PM
#20
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Join Date: Sep 2004
Location: peru
Posts: 11
well i use 90 here in Perú and it goes nice on my ka24de when i try with 97 or 95 goes better but here the price aree to high and everyday drive with 90 only thursday when i have some races i use 97 with octane booster and it looks very better. What do you think about octane booster???
03-14-2005, 04:17 PM
#21
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Join Date: Nov 2004
Posts: 276
hey smokie....didn't mean to be a dick man.......
Also, fords LIKE higher octane. Esp. the 4.0 ho motors. Our 94 pings like hell on 87, and runs REAL strong on 91. Most fords with over 50k. are like that.
Oh yeah. ONe more bs statement i have to put down. The guy that said higher octane has nothing to do with performance.......Maybe you just meant OUR cars....However, higher octane is REQUIRED for performance motors. Simple as that. Don't use= Knock, Knock, thwap, then......bOOOm. Try running a 500 hp. 383 chevy stroker on 87 octane. I think the alcohol in **** would make it run equally well!
Also, fords LIKE higher octane. Esp. the 4.0 ho motors. Our 94 pings like hell on 87, and runs REAL strong on 91. Most fords with over 50k. are like that.
Oh yeah. ONe more bs statement i have to put down. The guy that said higher octane has nothing to do with performance.......Maybe you just meant OUR cars....However, higher octane is REQUIRED for performance motors. Simple as that. Don't use= Knock, Knock, thwap, then......bOOOm. Try running a 500 hp. 383 chevy stroker on 87 octane. I think the alcohol in **** would make it run equally well!
03-14-2005, 04:37 PM
#22
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Join Date: Apr 2004
Location: West Covina/ Irvine
Posts: 2,515
I thin he meant as in increase hp. Anyways, slower burning fuels, higher octane gasoline, may burn too slow for an engine and may hinder performance. Whatevrer, 87 Arco gas works just fine for me 
03-14-2005, 06:18 PM
#24
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Join Date: Mar 2005
Posts: 18
The octane rating of your gasoline can be directly equated to its resistance to detonation. In a clean healthy engine, you would require higher octane to resist the detonation at higher compression ratios cause by either your build-up or boost, depending on how your engine is powered.
Higher octane does not give you a bigger bang, in fact the higher the octane the more the gasoline resists the bang, and prefers to burn.
Your compression ratio and the cleanliness of your cylinders, should be the cheif concerned when choosing an octane rating.
Octane refers to the chains of hydrocarbons created when the fuel is cracked in the refinery. The length of the chain determines the type of fuel; for example methane is just one carbon hooked to its buddy hydrogen, butane has 4 carbons, and heptane is 7, and Octane has 8.
Heptane and below doesnt like compression, and when placed under pressure it has a tendancy to ignite on its own. This is bad. We want a burn, because we are not blowing things up in our cylinders, we are burninating oxygen.
This behavior is great for diesel engines, which dont use spark to ignite thier mixtures, but instead, heat and pressure.
As with most things chemical, add one more atom of carbon and everything changes. Octance which has 8 carbons, loves compression. We love compression, so the relationship works. 87 Octane fuel has 87 percent Octane chains in it, and 13 percent something else...heptane probably.
EDIT: I should add one little weird thing. In a perfect world higher octane isnt bad for your car, however it can MASK an existing problem. If say, you have a carbon buildup on of your pistons. two things are going to happen. One is that the carbon has mass and therefore it takes up space, this reduces available space for the combustion chamber. This means higher compression which could cause detonation. Two, the carbon can retain heat between cycles and cause pre-ignition as well. A higher octane fuel would mask this problem by preventing some or all detonation, but the problem would still exist. This might require you to run a richer mixture to keep your EGT's down, which would cause loss of effeciency, might also blow out your cats, cause you to fail inspection etc etc etc. In this case the higher octance fuel has hurt you by hiding the truth.
Hope this helps.
JMB
Higher octane does not give you a bigger bang, in fact the higher the octane the more the gasoline resists the bang, and prefers to burn.
Your compression ratio and the cleanliness of your cylinders, should be the cheif concerned when choosing an octane rating.
Octane refers to the chains of hydrocarbons created when the fuel is cracked in the refinery. The length of the chain determines the type of fuel; for example methane is just one carbon hooked to its buddy hydrogen, butane has 4 carbons, and heptane is 7, and Octane has 8.
Heptane and below doesnt like compression, and when placed under pressure it has a tendancy to ignite on its own. This is bad. We want a burn, because we are not blowing things up in our cylinders, we are burninating oxygen.
This behavior is great for diesel engines, which dont use spark to ignite thier mixtures, but instead, heat and pressure.As with most things chemical, add one more atom of carbon and everything changes. Octance which has 8 carbons, loves compression. We love compression, so the relationship works. 87 Octane fuel has 87 percent Octane chains in it, and 13 percent something else...heptane probably.
EDIT: I should add one little weird thing. In a perfect world higher octane isnt bad for your car, however it can MASK an existing problem. If say, you have a carbon buildup on of your pistons. two things are going to happen. One is that the carbon has mass and therefore it takes up space, this reduces available space for the combustion chamber. This means higher compression which could cause detonation. Two, the carbon can retain heat between cycles and cause pre-ignition as well. A higher octane fuel would mask this problem by preventing some or all detonation, but the problem would still exist. This might require you to run a richer mixture to keep your EGT's down, which would cause loss of effeciency, might also blow out your cats, cause you to fail inspection etc etc etc. In this case the higher octance fuel has hurt you by hiding the truth.
Hope this helps.
JMB
Last edited by jbayles; 03-14-2005 at 06:29 PM.
03-16-2005, 09:28 PM
#25
Originally posted by s13_peacekeeper
gas doesnt really matter....higher octane just means bigger bang. it doesnt give you more power it just burns better.....smoother ride.
if you really want to know the ka-e was made for 87-89 octane and the ka-de was made for a 91-95 octane but it really doesnt matter like i said it just burns better. if you live some were cold are on the highway alot its a good idea to run premuim if not then it just a waste....
gas doesnt really matter....higher octane just means bigger bang. it doesnt give you more power it just burns better.....smoother ride.
if you really want to know the ka-e was made for 87-89 octane and the ka-de was made for a 91-95 octane but it really doesnt matter like i said it just burns better. if you live some were cold are on the highway alot its a good idea to run premuim if not then it just a waste....
Giving you less HP, and worse GAS mileage!!!!!!!!!!!
A stock KA24de is meant for 89 octane!!!!!!!!!!!!!!
03-17-2005, 02:03 PM
#27
i personaly used 93 at sunoco. i dont have any serious mod yet, all i had was no ac not powersteering
no emissions equipment, intake, megan dual exhuast and testpipe. and my motor ran fine with it( well did, the motor blew cause i was reving to high- 7800-8k and i didnt know about KA Crank issues then.
no emissions equipment, intake, megan dual exhuast and testpipe. and my motor ran fine with it( well did, the motor blew cause i was reving to high- 7800-8k and i didnt know about KA Crank issues then.
03-17-2005, 06:30 PM
#29
Originally posted by s13_peacekeeper
the maunual for the ka24de says use premuim....that is straight from nissan america, how did you get the ka-de is made for less?
the maunual for the ka24de says use premuim....that is straight from nissan america, how did you get the ka-de is made for less?
Your nissan car manual follows the "EPA" california smog standard of 89 octane..........
Sounds confusing doesn't it.......
If your not shure you should read and research the Chilton or Haynes manual, that is the bible to your engine and car, it states "use 89 octane"............
Last edited by BigVinnie; 03-17-2005 at 06:37 PM.
