89 vs 93

[jeff_man]

So the book says premium / super recommended so i have been running race track 93oc sense it's not to much more then the 89 stuff but on a 1.8 n/a dose it make a difference? i know about the difference in turbo cars but not n/a in terms of speed and motor care.

[Treibenschnell]

Nope... it shouldn't make a difference anywhere but your in wallet.

[jeff_man]

well after a 88turbo2 with 12 mtg with 93 anything i put in my 5 even if it's rocket fuel is a upgrade

[Adam Payrot]

If you've advanced your timing, it (higher octane) will help with detonation in the summer.

[Treibenschnell]

If you've advanced your timing, it (higher octane) will help with detonation in the summer.

I didn't think one was able to advance the timing on a '02 NB... at least not without some shenanigans...

[Adam Payrot]

I didn't think one was able to advance the timing on a '02 NB... at least not without some shenanigans...

I didn't know either... I know that some NB's you can get a few more degrees of timing; don't know the cut-off for that though. Generally speaking though, my statement holds. Whether or not it's been done is another thing all together

[icepenguin66]

All I have to say is if a car with that little hp (no offense intended) requires premium fuel, then either the car has a problem or the manufacturer has a problem!

[Radio-Active]

The statement about fuel grades in the owners manual of my 05 states that Miata fuel requirements: minimum 87 octane rating, 91 or higher is recommended.

MazdaSpeed MX-5 91 octane or higher is required.

[Miatamoto]

I'd definitely use 87 during the cooler months. You may need the detonation protection of 93 in the summer.

[channelmaniac]

On my 03 I can tell a BIG difference in the Butt Dyno and in the Wallet Dyno if I run anything less than premium (91/93 octane depending on state)

It costs more to fill the car up with lower octane as your engine will retard the timing automatically to account for knock and ping. You will feel the performance drop AND you will notice worse gas mileage - enough so that you will spend more money on fuel if you use the cheaper gas.

YMMV, that's just my experience with my 03.

RJ

[black roadster]

On my 03 I can tell a BIG difference in the Butt Dyno and in the Wallet Dyno if I run anything less than premium (91/93 octane depending on state)

It costs more to fill the car up with lower octane as your engine will retard the timing automatically to account for knock and ping. You will feel the performance drop AND you will notice worse gas mileage - enough so that you will spend more money on fuel if you use the cheaper gas.

YMMV, that's just my experience with my 03.

RJ

I thought the 03 required Premium. Don't all the Miatas with VVT require or at least recommend Premium? I think VVT became standard on the 01 remodel. On 90-00 Miatas, you are wasting money by using Premium unless you bumped the timing and need to prevent detonation in the summer months or your FI.

[Miatamoto]

I'd follow ChannelManiac's advice since he owns a '03. My advice comes from my experiences with the '94.

[POS Racing]

Our '02 Likes the Mid Grade, knocks like a fool on the cheap stuff, and only gets the top shelf for AXs or Track Days.

[icepenguin66]

I run about 13* timing on my 1.8 swap car and I run 87 all the time with no problems.

[Radio-Active]

I thought the 03 required Premium. Don't all the Miatas with VVT require or at least recommend Premium? I think VVT became standard on the 01 remodel. On 90-00 Miatas, you are wasting money by using Premium unless you bumped the timing and need to prevent detonation in the summer months or your FI.

Key word: Recommend

The only one that Premium is said to be required is the MSM.

But, as CM noted, if you get 2-3 MPG better fuel economy on premium versus regular, you break even on the cost per gallon.

[BAM!]

I run about 13* timing on my 1.8 swap car and I run 87 all the time with no problems.

i run 15-16* and dont knock/ping, im just being safe. 13 shouldnt be that bad....

just to toss it out however, racetrack isnt a top tier fuel, but quicktrip is, thier prices are usually the same (i dont really pay attn to it however.) if it was up to me, id at least buy a top tier fuel.

[channelmaniac]

Just keep in mind guys that the VVT cars run higher compression than your cars do. They DO need higher octane to run properly.