CanadianRX7

i have heard 92 and i have heard 87
which is the right one to use??

supergoat

I use 89 in my 88GXL

ajsuper7

all n/a's were set up to run best on the lowest octane, i use 87. ive done some testing and the car runs better on the cheap stuff...some people like 89 octane better, but not me

CanadianRX7

hmm alright i use 92 or 91 right now and i was just seeing what is best
but doesnt the higher octane make your engine last longer and doesnt it give u more hp?

rxspeed87

I have a 87 N/A and tried to run 92 octane and my mpg dropped a lot
when I was running my car without the tps (came that way when I bought it) I was getting about 280-300 miles per tank on the cheap 87 octane but the moment that I put in 92 I was lucky to get 200 per tank

as far as performance the car had a real problem with lagging once I put the more expensive 92 in there, and the car wanted to
run hotter as well. right now though my car is bone stock

from what I understand the way the rotary works and the shape of the combustion chamber and how it is so large you want a quicker burning flame to get better milage and power or else with the higher octane since it is a slower burn a lot of it gets wasted burning in the exhuast.

correct me if I am wrong here guys. I admit I am still new to the rotor world

tweaked

iTrader: (4)

I have done testing of my own. I have a fairly modified 88 n/a. When I use 88 or lower octane fuel. My motor makes an odd noise I have yet lto find when I accelerate hard in 1sst 2nd and 3rd. this doesn't happen when I use the 89 or higher. Generaly, I use 90 or 91 when available. I still get 25.6 mpg on the highway, which was beter than the 24.? with lower rated fuel. I do knotice slitly lower mpg if I go any higher.

urshadow

If you have a 13b use 89. unless you have nonstock turbo set up and/or custom ecu, fuel curve. Stock rotors can't burn all of that high octane fuel. so your realy just wasting money with anything higher than 89.

Evil Aviator

The octane rating of fuel is actually an anti-knock rating, not a power rating. In fact, the higher-octane pump gas is actually "watered down" with inert or semi-inert compounds so that it doesn't detonate. Your NA car will actually get more HP with 87 octane. Cars with high compression and/or forced induction need the anti-knock qualities of high-octane fuel just to operate, so they take the hit in fuel quality and make up for it in quantity.

MikeL

Yea, what he said.

Use the lowest octane that does not allow detonation. You'll then have the best performing and, best gas mileage gasoline.

With a n/a, 87 octane is likely the best thing.

If you ping on 87 octane with your n/a, something is wrong with the car.

Mike

jizzajuice

REALLY?! Wow... that's cool stuff. I'm used to thinking that putting in the highest octane will get you the best results. How WRONG I was!! Hey, Im gonna try that once I'm done with this tank. Thanks fellas!

Peace,
AJ ^_^

MaxRX7

I always used to put the highest octane, then the gas prices went up, and my octane choice went down. I couldn't tell a difference, so I am running it with 87.

CanadianRX7

right on 87 octane it is
time to save lots of money on gas yay!!

supergoat

looks like I'm gonna start useing 87

mazdaspeed7

Mazda programmed the ECU on the FC to use as low as 83 octane gas. I use 87 normally, but every few tanks I put 89 in to clean the fuel system out a little. The higher octanes have more detergents in them and burn a little cleaner than 87. I have my timing advanced a good bit, and still use 87 without any problems.

flubyux2

NA's run the best, w/ the lowest octane u can find. due to the rotary design, a faster-traveling flame front is the BEST. (low octane has less knock/detonation inhibitors in it, thus, more volatile)

FYI, when mazda was racing their factory backed RX7s, in the IMSA/GTU manfacturers championship (check out the cool sticker on ur hatch!) they won those races using 79 octane.

lower is better for NA.

for turbo's, standard piston engine beliefs hold tru; Higher octane is better.

chris