I am a similar former Mustang (03 GT) owner... had an Accord due to growing family, but BORED TO TEARS WITH IT!!! Someday the Mrs. will understand...

Anyway, Purchased my 2005 RX-8 last Wednesday and WHAT A CAR!!! This site it great info (and similar to sites where I educated myself on my Stang) and I'm learning there's a lot to this car. Have my fingers crossed I don't have many problems but I LOVE THE LOOK, DRIVE, SOUND.. all of it!!!

Researched everything out there and kept coming back to the RX-8... with this I can still put kids in the back if need be... keeping it for years to come (unless it's a lemon... <knock on wood>....

One question: any difference running 89 Octane vs 91? Did the same with my Stang (varied the two) and no problems ever...

Thanks ahead of time for any info/pointers and look forward to sharing with you all for years to come!!
Russ

 

rdgdawg, congratulations and welcome.

I use 89 all the time. Lots of people here use 87 too. I find that 89 is no trouble at all as long as you are getting a good tank (name brand). Get some mild detonation with an off brand.

Now be prepared for some flames. There are quite a few threads about octane.

 

I use 91
better safe than sorry

 

85 degrees and lower w/normal driving i use 89, any higher temp or i plan on pushing the engine i use 91. i have never used 87. and yes beware the repost/search police on this site

 

use 91+, the ~$1.50 savings by using 89 isn't worth it IMO.

 

30,000 miles. Only use 93 octane . No problems whatsoever. I am hardheaded, though.

 

^Same here. I only use 93 octane.

 

I use 93 every three out of four times, 89 once out of four. I started out with 87 the first week I had my 8...but stopped soon enough after noticing better performance with 93. Yes, I noticed it.

 

cali doesnt have 93 often or I would use it

 

My friend who is a rotary mechanic said that the octane level of gas determines how "stable" it is. The higher the octane the more stable. This is important because you don't want the gas to ignite pre-maturely or too late- ie stability. The conditions depends on how you drive and the environmental factors.

He said that if you like to drive the car hard and/ or in varying conditions that it's best to use stable gas- ie higher octane. Otherwise, you could get degraded performance, and/ or damage the engine.

 

GREAT info... thank you much for the input. Here in WI even though it is cooler I think I'll roll with the 91...

 

Welcome...

You should be fine with 89. Especially now that winter is arriving and your air intake charge will be much cooler.

Oh, and after your engine is properly warmed-up (~5 minutes after the temp gauge rests), don't be afraid to take the engine until you hear the beep. The engines are made to rev, so have fun and use it.