RoTarYsFoReVeR

Hi everybody, been doing a lot of highway travel recently and wanted to know if it will hurt my 8 at all by putting regular gasoline into it since I will just be driving at cruise speeds of 70-80 mph (and also to save a tad bit of cash since these gas prices are soooo cheap lol... )

Aseras

I've got 62k+ miles on my rx8 and I almost always use 87.. but it has to be good quality 87. If it stop at a noname place and gas up with the cheap sutff, my car will start running like crap. sometimes you still get crap gas.. if the car was running good and within 20 miles of gassing up start acting funny, you got some crap gas. You'll especially be able to tell if you get a rough idle. only way to fix it is to top off with 93 and wait it out.

Gas that has a lot of ethanol ( look for pumps with ethanol stickers or when you are out west ) kills my gas mileage, the car runs ok, but feels lacking on power due to the reduced energy of the ethanol.

Using good 87 on long trips and keeping my foot out of it has netted me mid to high 20's. My record is 27 mpg, and I've had 2 400 mile tanks, normally I get 300-320 & 21-22mpg for normal commute.

RoTarYsFoReVeR

Wow, that sounds great Aseras, thanks a lot... so by "good quality" you're saying Like Exxon/Mobil, Sunoco, BP etc?

RoTarYsFoReVeR

anybody else use 87 on long trips???

icyur2

Yup..I avg. 20-21..but..I don't go speed limit..so..might amount to a lower mpg

L8APEX

I tried using 89 for a few weeks, right after Hurricane Katrina and our gas prices were outrageous. my mileage did not change, but the car felt a little sluggish, and I got a little of the rotary ping, so, back to 93 for me. the cost difference is not that much in the long run.

Butch Brown

I have 31,000 miles and use 87 Shell or Citco never had a problem recently checked milage on a 130 mile trip and it was over 22 mpg.

NoTears316

I have never used anything under 91 octane. Now that I'm back on the east coast, I use 93 all the time.

valpac

iTrader: (2)

When I did the math, using 87 vs 93 saves a whopping $20 a month. Hardly worth the drop in performance, engine life and overall feel. To me.

Georgia8er

Mine runs fine, if not a little better on 89 octane. I only tried it because some other forum members had noted the same thing, some had noted the opposite as well. I definitely didn't do it for money savings, like val said you're not saving much.

Easy_E1

iTrader: (2)

It was 106 here today, and if I put regular in my tank the engine would die.
PING PING PING. Lower octane does not work when the temp is 106 and humidity is 5%. The gas burns before it hits the combustion chamber.
I'm sorry but I have to run PREMIUM.

Aseras

when i say keep my foot out of it, i drive 75-85 most of the time.

Where it's hot like in AZ change your plugs, get rx7 plugs (NGK bur9eq, bur7eq ) and change em every 15,000 miles. they are $5 each. Do your redline every day, keep the carbon out and keep the plugs fresh and the oil topped off and it'll never knock on 87.

1stgen8

iTrader: (1)

I've tried 87 a few times and don't care for it. Car feels sluggish and it burns up quick. My car seems to run best on 89. Performance wise I cant say 93 is better in my ride than 89. One thing I do know is 93 burns up quicker under normal driving conditions than the 89. I get about 22 - 24 miles per gallon if I set the cruise using 89.

Georgia8er

I did a little better than 24 mpg on a long trip recently, cruising at 75. Did a take cruising at 80 and went down to 22 mpg. There's a really fine break point on the fuel economy. This was with 89 octane gas.

GRGJTSN

I haven't bought a tank of anything less than 93 in like 4 years (in several different cars)...but one day a couple weeks ago I needed to fill up and 87 was 30 cents a gallon cheaper, and I had been reading about the difference in octane here on the site, and how some people prefer the lower octane fuel...so I decided to try 87.

I'm on my second tank of 87 now, haven't had any problems, no pinging, and haven't noticed a drop in performance or mileage, still getting 21-22 mpg avg. I guess I will stick with it until I have a reason not to.

RoTarYsFoReVeR

thanks a lot everybody for the response... I've done a few trips lately and I don't get any difference in gas miliage using 93 vs 87... no pinging, and maybe just a tiny difference in performance but thats about all. Getting about 21-22 mpg tops