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-   -   110 octaine IDEA lemme know. (https://www.rx7club.com/1st-generation-specific-1979-1985-18/110-octaine-idea-lemme-know-230966/)

RRTEC 10-09-03 12:47 AM

110 octaine IDEA lemme know.
 
Ok i was at my desk today dreaming about a summer day in my seven. I was at a stoplight and a riced out Eclipse pulls next to me. Reving his engine...About that time i flick a switch on the dash and smile back at him...Blow him away (of course). But my idea is what if I put a small fuel cell in the car somewhere filled it with 110 Turbo blue ran a seperate fuel pump to it and t'd it into the fuel line into my holley carb? Do you think this setup would raise the octaine in the gas enough for me to tell a difference? Or should i make it so when i use the TUrbo Blue the regular gas doesn't flow it waits untill i switch back to the regular tank and 87 fuel? Is this at all worth a shot. lemme know i'll do it this weekend if you think it will be worth it.:rock:

Pedestrian X 10-09-03 12:54 AM

yea.. try it.. but i think higher octane fuel isn't quite necesarry in roataries.. I think most people go up to teh good stuff after they have a ncie turbo setup and wanna fine tun ethe timing and setup and what not..

Gregs 10-09-03 01:12 AM

if u flipped that switch at a stoplight it would take at leats 10 seconds for the high octane fuel to get through the lines and reach the carb

RRTEC 10-09-03 01:27 AM

True...But still if i had time to think about it. or even just for autocross runs you know...

Gregs 10-09-03 02:21 AM

yeah, i like the idea, always goood to come up with new ideas

riffraff 10-09-03 05:13 AM

except for that if your seven is n/a , then it will probably run worse on higher octaine. you are best off running the lowest that you can

1984special 10-09-03 06:53 AM

I heard some race teams in the early 80s even used 80 octane! That's like piss and water... :)

vipernicus42 10-09-03 07:10 AM

Hey Guys,

Interesting, though pretty much useless idea in this case.

There have been threads about this countless times before, that rotaries don't run better on high-octane. Those race teams ran 83 octane btw, and had to bring it to the track themselves because you couldn't get anything that low at the track. Hell, I can't even get anything that low at the pumps!

But yeah, the only people who use higher octane are people with large turbo setups, because the pre-compression the turbo provides increases the chances of pre-ignition, which is a bad thing and causes "knocks". Octane resists detonation, which is not necessarily a good thing. It makes the gas *harder* to ignite... Now some would ask "Why the fuck then does high octane fuel make pisst-on cars run better" and the answer is again compression.

Pisst-on cars have a higher rate of compression than rotaries, and since gas will ignite w/o spark if you just damn well compress it enough they have to put something in it to prevent it from exploding until the spark sparks it. So Octane is added/increased to make sure the cylinders only fire exactly when they're supposed to, preventing misfire and pre-ignition which fight the force of the cylinders that *are* firing at the right times.

The rotary won't necessarily run a huge amount *better* the lower octane you go, but it will run worse the higher octane you go. Run QUALITY 87 Octane. When I say quality, I mean that some gas companies have crappier gas than others because of 1) what they put in it 2) what they leave *out* of it and 3) how they refine it. You'll have to test how your car runs on different fuel yourself.

Anycase, while it's a great idea, it wouldn't give you any improvement, and the space in your (do we call it a trunk?...) back of your car would be better used for a wet NOS system, although I hate nos... I really hate nos...

Peace out
Jon

RRTEC 10-09-03 11:18 AM

yeah i hate "NOS" too, but thanks for the feedback. I wasn't aware that higher octaine was poor running in the rotories..
thanks

O 16581 72452 5 10-09-03 11:35 AM

What's wrong with nitrous?

QuagmireMan 10-09-03 12:40 PM

i dont think higher octane is any better, only if your hotter or have higher compression. big misconception that people think they need higher octane for their vehicals when 85% of vehicals dont need the high test.

wwilliam54 10-09-03 05:41 PM

maybe a wet nitrous system hooked to a fuel cell with 80 octane

mmasid 10-09-03 08:31 PM

vipernicus42 knows what he's talking about. High octane fuel is really only good for turbos and other high compression motors.

QuagmireMan 10-09-03 08:47 PM

higher octane prevents detonation

DriveFast7 10-09-03 09:16 PM

Over 8 years I consistantly got better gas mileage and the butt dyno said more power with 91 Octane gas. On a 12a stock port, and then streetport. Hig flow carb and exhaust system. n/a.

Can someone explain this and why high octane is not good for n/a rotary?

And on the bridgeport my engine builder reccomended 89 octane for a little more detonation resistance than what 87 provides.

Just more "fuel for thought" :) :):):):):):):)

To answer the original question, before you invest in a 110 octane cheater system take your car to the dyno and run it on 87 pump gas, then replumb the rear of the fuel system to pull from a gas can full of 110 octane and let's see once and for all if there is more powah.

If so you can plumb in a cheater gas tank with a separate fuel pump and Tee it into the fuel line right before the carburetor. Rev the motor real good at stoplight to burn out the low octane stuff and draw 110 into the carb in no time. Add some NOS and you might have a real winner!!!!

metalliman 10-14-03 07:02 PM

The only way you're gonna get more horsepower out of high octane gas is by advancing the timimg considerably. However, in rotary engines, you can easily run 20 degrees BTDC on 87 octane.

If you wanted to run N20, or some type of forced induction, then the high octane would be very useful. However, having a second fuel tank might require you to have to some sort of purge valve, to get rid of the air in the lines. What may be a good idea, is to use a second tank, and fuel pump of course, to hook up to a N20 wet system. This way you could still use your 87 octane for normal driving, and 110 for fun. However a purge valve would still be necessary.

mar3 10-14-03 08:24 PM

Over 15 years I consistently noticed no difference in gas mileage or power either with 87 or 91 Octane gas. Only difference was my wallet was lighter from the price of 90+ octane gas. On a 12a stock port, and then the RP big street-port. Stock Nikki but with high-flow cat and full exhaust system. All n/a.

Can someone explain this and why high octane is not necessary for n/a rotary?...:p:

Actually, that's not necessary...a simple search could give me all the info without bothering everyone on the current boards...


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