harash87

So I have a 05 Rx-8 with about 9,500 miles. On the tank it has a sticker that says premium recommended but i read some where that unleaded was fine. Premium here is about 23 cents more per gallon. I spoke to some one from the dealership and they told me that premium is a must that the 05 have an outdated sticker is that true. DO I REALLY NEED TO SPEN MORE MONEY ON PREMIUM. Or dose it just perform better. Dose unleaded ruin the engine. Too many Question sorry about that...

Brettus

iTrader: (2)

I'm thinking of a word that starts with 'S' ....... Can anyone guess what it is ?

harash87

No

RX927

iTrader: (1)

SEARCH! yay i win one more mpg! there are countless threads but to make thing short and simple if u mean 87 oct to 93 ( depending on state) some get better gas mileage on 87 worse on 93. try it and if the car feels more sluggish than usual switch back to premium. I reccomend you wait till your tank is empty and before filling up with your new choice of octane reset the ecu both ways ( look it up in the diy section).

Shini

Let me guess! Search?!

By the way, just use Premium. There's no real reason not to. At most that 23 cents a gallon you save per month would add up to a dollar menu meal from Mcdonalds. Why not run the premium since it's better for your car wether or not it's a sports car or not?

swoope

iTrader: (5)

wow,

you do not read well....

use premium...

DO NOT USE UNLEADED, it will mix with the syn oil and you will blow a connecting rod... it is bad for the wrist pins also...

but what do i know.. 87 oct pump gas works great..

beers







































btw, for the stupid... all car pump gas is unleaded in the usa..

jskup1

iTrader: (7)

If you're worried about an extra $3.95 per 15 gallons of gas, you should not have bought this car.

Fanman

Some people have had cars that have done OK on 87, others have had pinging issues. This subject has been discussed ad nauseum. There are some people that think octane has no effect on hp, & some do (timing, etc). Search & you will find long threads on this subject.

Bad_Bob

Here Here. Do not be cheap.

nycgps

iTrader: (1)

lol

I thought we only have unleaded gasssssss ????????????????????????????????

Does that mean Premium is LEADED ?!?!?!?!?!

LOL LOL LOL !!!!!

You mean Regular and Premium. I use Premium, not looking back.

and dont be cheap. if you cannot effort the extra 23 cents per gallon, you shouldnt be driving at all.

reaper1

Agreed 100% ....... and I thought the word was.......S....TUPID......

Jethro Tull

iTrader: (6)

The concern is detonation, or "pinging" or "knocking". The rotary has a high compression ratio, and is more susceptible to it than most lower-compression piston engines. Severe instances can cause engine damage. You'll get a smoother running engine, statistically, going with the higher octane, and lower your risk of damage. Your driving style has as much to do with that risk as the octane level, however. YMMV.

mac11

iTrader: (1)

The renesis is 10:1 compression. That is not high compared to most piston motors. That is a very common compression ratio for a naturally aspirated street car. Turbo cars are generally lower compression if they plan on running more than a BAR of boost on pump gas. down to ~8.5-9:1, typically.

Jethro Tull

iTrader: (6)

There you go, I'm out of the loop. The last time I actually took apart an engine was in the '70's- and the compression ratio was something like 6.5:1. And almost every large V-8 in the '70's would knock on hard accelleration using low-octane fuel.

Note that almost ALL diesels knock all the time- and they are around 18:1 if memory serves. I'm supposing that this is because ignition takes place well before TDC, much more so than a gasoline engine.

So, by extension, can we assume that all modern piston engines can still experience knocking under hard accelleration and using low-octane fuel?

Keef

I don't experience any "knocking" using 87 octane. But than again I'm running with a Race flash, so I'm pretty sure it's set too work different under WOT...

Silver_Surfer

My car runs great on 87 except in summer or when the weather is HOT. The pinging goes away when using 89-92 oct.

****IT'S NOT ABOUT THE MONEY!!! MY 8 LOVES(RUNS BEST) 87oct!!***

Jedi54

iTrader: (7)

premium... why would you risk a $30,000 car over a couple bucks?

deadphoenix52

i use nothing but shell v-power.

mac11

iTrader: (1)

Thats not quite accurate. My body guy runs a '70 Camaro with 10.5:1 and makes 450hp on pump gas.

Also this about the Mopar powerplants..

http://www.hemmings.com/hcc/stories/..._feature6.html


And remember they were working with ~80 octane gas back then which may account for why "knock" was alledgedly so prevelantt.

Jethro Tull

iTrader: (6)

What's not quite accurate? I never worked on high-performance engines, just kept my mom's station wagon and buddy's Rambler running. And they were not anywhere near 10:1 compression ratio- that I recall, at least.

I was there back then, nothing "alleged" about knock in those days. Almost every stock, non-high-performance American car I drove had it, regardless of make or model. My '74 T-bird was a terrible knocker- so was my dad's '70 Delta 88.

Anyway, pre-ignition is what the dealer has told me is the reason for Mazda recommending high octane fuel. Apparently the apex seals are vulnerable to damage from it in extreme cases. My Explorer (somewhat more recent vintage than '60's & '70's cars) also must have at least 87 octane or it knocks terribly, under only a modest accelleration.

I agree with others who have already stated that what's a few cents per gallon with a $30,000 car? Mazda recommends it, I'll use it. But by all means, if anyone wants to go with lower octane fuel, I'll not try and talk them out of it.

Fortunate Few

iTrader: (2)

premium is the best if you ask me i can definatly feel the difference. its gotta be at least 91 octane.a place here sells 101 octane its supposed to be "racing" gas. idk about that but it seams pretty tight.

StewC625

Or do like I do - just use the regular! At 12,000 miles/year of driving, and 14 mpg average, it's $200/year saved - not big shakes, but since there's no performance benefit that I can see or feel, I see no reason to spend the coin.

Shini

101 huh? That's something you'd just keep in a canister and run while you're at the track, do they actually serve that at the pump?

mac11

iTrader: (1)

They never had close to 6.5:1, either.


1962 AMC Rambler
Year 1962
Make AMC
Model Rambler
Engine Location Front
Drive Type Rear Wheel
Body Material Unit Steel

Engine
Engine Configuration V
Cylinders 8
Hydraulic valve lifters
Aspiration/Induction Normal
Displacement 327.00 CU IN. | 5359.5 cc. | 5.4 L.
Valves 16 valves.
2 valves per cylinder.
Valvetrain OHV
Horsepower 250.00 HP (184 KW) @ 4700.00 RPM
HP / Liter 46.3 BHP / Liter
Bore 4.00 in | 101.6 mm.
Stroke 3.25 in | 82.6 mm.
Compression Ratio 8.7:1
Main Bearings 5
Fuel Feed Carburetor Holley 2040 2-barrel carburetor
Block Cast-iron

4me2

If there isn't any knock, use regular.