What grade gas in a stock KA?

[lbrowne]

I always thought it was the entry level octane??

Now I know some on here will say they put the high grade stuff in, makes them feel all warm n fuzzy inside, but in older NA cars most times they can't utilize the higher octane. (like my 93 Explorer I had, higher octane was a waste to use)

I'm not sure however, if this is the case with the sohc/dohc. I know folks use higher grade with turbo upgrades or when running advanced timing. So I'm wondering for stock to mild bolt on KA (intake and exhaust tops)

So since I don't have an owner's manual, don't the KAs use/require 87 octane?

Please provide hard evidence on your answer, and not "my car runs better with it so all KAs require it!"

Cheers,

lbrowne

[spank044]

You can run the cheap stuff for now, but when you start changing cams, injectors, intake manifolds, itbs, or FI, then you will want to runner a higher grade fuel.

If anything just do a complete tune up: plugs, wires, cap, rotor, all fluids and filters, clean all your sensors with an appropriate cleaner. Remove EGR if you can, or at least block it off. Just do a complete clean up of the engine bay and you will probably feel a little better response and maybe a little more power.

PS- DON"T BE CHEAP!!!!!!!

[H8tred]

I have to run at least 89, if I run 87 I get a fair amount of ping under load. Bone stock aside from what looks to be a cheap *** egay intake that was there when I bought the car.

[lbrowne]

So no hard evidence as to what is indicated in the manual?

I have my gas mileage maintenance items done, this thread wasn't intended for that - but thanks for the replies

[H8tred]

I don't know about yours, but the inside of my gas door clearly says "Premium recommended for maximum performance". If you can run 87 with no ping, go for it. If you can afford to go with 91 at every fuel stop, go for it. It's really what ever works, and pinging is some pretty hard evidence. However your motor may not ping on 87... My personal preference is Texaco 89, and I normally always go to the same station for consistency.

[lbrowne]

I'll have to check on my gas door too, I never ever looked there. If it was there, it's probably long gone now.

[lbrowne]

Theres a sticker there that says:

"Unleaded Fuel Only"

[Felipe]

i use 91

good burn dosent last long....

87 bad burn dose last longer

[H8tred]

Theres a sticker there that says:

"Unleaded Fuel Only"

Mine says that on the same sticker... I just figured I'd leave that out haha.

[Steev]

I just got my 240 a few weeks ago (but I love the car so much I've been filling up a lot ) and have been experiementing with different octanes. I get the most fun with my right foot with 92, the least fun with 87. I get the best mileage with 89 with almost the same amount of performance.

I have been filling up with chevron exclusively so far. I am going to try the mohawk 89 next as they offer it at the same price as 87.

[sleepyeyes]

you could also use the cheap stuff and use that fuel add. stuff once every month, worked pretty well for me when i had my first 240

[Dave_Dynamite]

what does "ping" mean?

[Kraelic]

I have an owner's manual for my 91 240sx and it calls for mid grade on the ka24de.

[Bigvinnie]

OWNERS manual guy's, don't be retarded to knock and ping. This thread should be closed based on stupidity.9.5:1 compression should tell you to use 91 octane or better.KAE's can use crap 87.Research Heptane to Octane rating's more heptane = a faster burn which is needed for lower compression under 9.0:1CR's. More Octane is a slower burn off used for higher compression engines above 9.1:1.Timing and fuel dumping can slightly change the rating of fuel you use.This is based on natural aspiration. Turbo charging of coarse changes everything I just said do to increased flame front, brought about by BOOSTING.

[k.i.s.]

i have a 97 owners manual...and this is exactly what it says

"Fuel Recommendation

All models are designed to operate on unleaded premium gasoline with an octane rating of at least 91 AKI (anti-knock index) number (research octane number 96)

if unleaded premium is not available, unleaded regular gasoline with an octane rating of at least 87 AKI (research octane number 91) can be used.

However, for maximum vehicle performance, the use of unleaded premium gasoline is recommended"

it says the same thing about maximum vehicle performance on the inside of the fuel filler lid

[Bigvinnie]

i have a 97 owners manual...and this is exactly what it says

"Fuel Recommendation

All models are designed to operate on unleaded premium gasoline with an octane rating of at least 91 AKI (anti-knock index) number (research octane number 96)

if unleaded premium is not available, unleaded regular gasoline with an octane rating of at least 87 AKI (research octane number 91) can be used.

However, for maximum vehicle performance, the use of unleaded premium gasoline is recommended"

it says the same thing about maximum vehicle performance on the inside of the fuel filler lid

So is that before or after the fact that 5% and 10% ethanol have been added to gasolines for the past 5 years? Ethanol drops BTU's, it also naturally drops knock and PING it changes the (AKI). Believe me 91 octane is fine. They don't sell 96 hardly anywhere in California.

[LayNLow240]

my kade runs like **** unless i put at least 89 in it. if i put 87 in it she will start bucking and wont idle worth a ****.

[240sxRAOR]

The cheapest grade is always crap and it will hurt any car overtime. My moms chevy sounds like its brewing coffee in the engine bay and if you run the good gas the brewing sound goes away. I say always run at least the mid grade fuel in any car, you realy don't save much by using 87 compared to the 89 and besides you'll probably have to change your injectors at some point because of the cheap gas and then you can ask yourself was it realy worth it.

[Bigvinnie]

The cheapest grade is always crap and it will hurt any car overtime. My moms chevy sounds like its brewing coffee in the engine bay and if you run the good gas the brewing sound goes away. I say always run at least the mid grade fuel in any car, you realy don't save much by using 87 compared to the 89 and besides you'll probably have to change your injectors at some point because of the cheap gas and then you can ask yourself was it realy worth it.

Soo if I run a 8.0:1~ 8.9:1 compression N/A engine, I would need better fuel than 87octane???C'mon man all engines have different tolerances. 87 octane has a high heptane burn needed for lower compressions. If you put high grade fuel in a lower compression engine it will run like shiat.

[Soravia]

I had a Precis 1.5L SOHC that leaked oil like in heat and it sounded much better with 96. Even then, AP fuel station I used to go to had much better feel than crappy RaceTrack.

[lbrowne]

Lowest grade is not something that is going to hurt a car over time. Like it was said before, all engines have different tolerances. If you truly believe that lower grade is harmful to all motors - thanks for coming out. lol

Anyways, so no hard facts huh? I might actually contact nissan, they might have that in their system. I'm constantly getting 23-24 mpg all city so I can't complain. With gas prices climbing the way they are, I think I'll stick to the cheap.

[glitched]

Lowest grade is not something that is going to hurt a car over time. Like it was said before, all engines have different tolerances. If you truly believe that lower grade is harmful to all motors - thanks for coming out. lol

Anyways, so no hard facts huh? I might actually contact nissan, they might have that in their system. I'm constantly getting 23-24 mpg all city so I can't complain. With gas prices climbing the way they are, I think I'll stick to the cheap.

There are "hard facts" in this thread, but a lot of misinformation as well. see K.I.S post about his 97 owners manual. also higher compression motors like the KADE do perform better on recamended octane.

Even more important than octane is if your fuel contains ETHANOL!

those comparing power and mileage to different grades results go completely out hte window if they have different levels of ethanol. You will get more mileage out of gas with out ethanal as ethanol has inherintly less energy than regular gasoline.

low grade is not "crap fuel" its not poorer quality, it doesnt have less energy, it just has less resistance to ping.

i would rather run lower grade gas with no ethanol than higher grade gas with.

In my area Shell has signs bigh signs out proudly proclaiming that their gas doesnt have ethanol... so i use v-power...

[Bigvinnie]

In my area Shell has signs bigh signs out proudly proclaiming that their gas doesnt have ethanol... so i use v-power...

Thats not true. By law shell has to phase out of MTBE and it is not legal to use in California. MTBE was phased out for it's environmental hazards (acid rain) and changed to ethanol for prevention of petro gumming compounds from gumming injectors, and valves, it also burns cleaner than petro, so it has become mandatory. If your fuel comes from a refining plant in California (saudi middle eastern oil) it has 5%~10% ethanol in it and that also depends on the blending. A winter blend gasoline will be different than a summer blend gasoline. It can also contain anywhere from upto 2% oxygen enrichment.

BTW most manufactured gasoline is all the same one manufacturer refiner, and many suppliers ( Redwood Petroleum=Valero, Shell, Exxon, and so forth) As far as I know chevron uses there own refineries and they have been doing a lot of experimenting with ethanol lately, they are even a heavy investor in it unlike exxon.


Modified by Bigvinnie at 5:19 PM 5/4/2007

[H8tred]

low grade is not "crap fuel" its not poorer quality, it doesnt have less energy, it just has less resistance to ping.

Ping is the precursor to detonation. The reason the 87 makes my engine ping is because it takes less heat to make it burn. That's why turbo cars have to use premium. So that on top of the heat and compression added to the intake charge, the fuel doesn't explode before the piston is ready to go down. The actual pinging sound that you hear that sounds like a high pitched rod knock is the fuel exploding somewhere between the piston traveling up, and TDC.

It's one of those things man, running a higher grade than your car needs will do nothing but empty your wallet, and in some cases give you less mileage as I noticed in my civic. However, people who have to run mid or premium can't go down the grades as it could result in a catastrophic event. So those who have to use Mid and premium can indeed look back on the others and say they are crap fuel, as it is more or less a more "crude" formula with more impurities. However, that's exactly how it was engineered to be, a cheap fuel that works for most.

[Soravia]

Gas in FL is now past $3.0 for Hi grade. I use Hi-grade only since my 190k 240 makes 25/25. ^_______^

Sometimes I make better milage in City compared to Highway, all thanks to a manual transmission with clutch.

Low-grade or Hi-grade it really doesn't make a difference in milage to my KA. But I prefer to have my engine running smoothly than occational pings and knocks. Hell I even setup my exhaust so that I can hear if the thing fires down the downpipe.

[Bigvinnie]

Gas in FL is now past $3.0 for Hi grade. I use Hi-grade only since my 190k 240 makes 25/25. ^_______^

$3.71 for 91 octane here in California. This gas price stuff sucks. I know I am being gouged at the pump. When is our government going to do something about it!!! Really I live 40miles away from 2 refineries I should be paying the most affordable prices not the most expensive.

[neverlift]

when we no longer NEED technology from japan and stock GIVING it to them for less then what we buy.

better question would be why noy use OUR oil,and not that of the country we are at war with?

[Bigvinnie]

better question would be why noy use OUR oil,and not that of the country we are at war with?

Easy answer to that.. Why should we have to pump our Alaskan reserve now, when oil becomes less abundant you can sell it for more later at a much higher price to other countries. Really oil is black GOLD, it is like a savings account. It collects interest as the demand goes up. It has nothing to do with environmentalists fighting over the natural wildlife of Alaska.

[neverlift]

yeah but why sell it if we are TRYING to save it ....