"MPGiata" modding thread: aiming for 50 MPG with a 1990 Miata. Update: success, 55 MPG!

[MetroMPG]

HELLO

I work at CBS National News and doing a story on saving fuel and hypermilers. I would like to show some DIY modifications and saw your miata posting. Can I use these pictures in my piece. We an credit youon screen with your name …let me know

My prediction: it'll be a "lighthearted" segment along the lines of:

"Look at the crazy things high gas prices are leading to, LOL!"

I'm fine with that.

PS: this is the pic they asked to use...

[Gasoline Fumes]

That's a loooooong antenna!

[Ecky]

Originally Posted by MetroMPG

My prediction: it'll be a "lighthearted" segment along the lines of:

"Look at the crazy things high gas prices are leading to, LOL!"

I'm fine with that.

PS: this is the pic they asked to use...

I wouldn't mind asking some questions too. I'm headed overseas soon and it's a 50-50 as to whether I can bring my Insight. I'm strongly considering a Miata if I don't.

Couple of questions:

What do you think about the 1.6 vs 1.8? The 1.6 seems to have been available all the way until 2005 in other markets, and it got new lifters (I guess an unreliable point), but never got VVT. It also was always paired with a 5 speed.

The NB2 got a 3.6 rear in other markets, but I'm uncertain if that was only when paired with the 1.8 and 6 speed. It's hard to find facts on this. Would you opt for the 1.6 and 5 speed, or if you had the option, a 1.8 + 6 speed (slightly shorter top gear) + 3.6 rear?

I've read through the thread a couple of times, but I'm still impressed by your results. Most seem to have a hard time breaking 30mpg in an NA. Where is the low-hanging fruit?

[MetroMPG]

Originally Posted by Gasoline Fumes

That's a loooooong antenna!

YKYAEM when... the thing you notice in that picture is the un-deleted antenna.

[freebeard]

I think skegs are worthwhile. Here on a barn find Oldsmobile station wagon.


barnfinds.com/1961-oldsmobile-super-88-fiesta-wagon/

[MetroMPG]

Originally Posted by Ecky

What do you think about the 1.6 vs 1.8?

Know what? I've only ever driven the NA. An aunt bought one new in 1990, and then mine. Nothing to compare it to!

I've read through the thread a couple of times, but I'm still impressed by your results. Most seem to have a hard time breaking 30mpg in an NA. Where is the low-hanging fruit?

Keep in mind my driving environment & style is highly optimal. Most of the car's use is very relaxed scenic route cruising (with lots of engine-off coasting where possible). I almost never drive on roads with >50 mph / 80 km/h speed limits, and a fair chunk is on roads with 70 km/h limits.


I haven't ABA tested anything on this car. But based on a CFD analysis I saw somewhere, the big-ass airdam plus grille block are probably the 2 most effective mods.



I also think the tonneau may be pretty helpful, based solely on the fact that it cuts down noticeably on wind noise vs. running without it.

[Xist]

Our neighbor just bought a red 1992 Miata with 112,000 for $1,000 for his grandson when he turns 16. He says that it runs and drives great, he just needs to clean it and replace the convertible top.

The police are going to know the kid well.

I don't look forward to the comments on the hit piece.

[MetroMPG]

^^ Super delayed response... sorry!


But wow: $1k is an amazing deal for a roadworthy Miata. Could easlily flipski it and probably triple his money. (But then what would he buy?)

I don't get the "hit piece" comment!

---



I scored a set of half worn Bridgestone Ecopia 422 Plus LRR tires. 195/65-R15.

These are for the back wheels, to raise gearing a few more percent vs. the dry rotted 185/65-R15 mystery tires that are on it.

We'll find out in late July how they work! God willing and the creek don't rise.

[AJI]

Amazed by your results with this! Just had a look back at the two I've owned in the past, both 1.6s, one UK market and the other a JDM import.

Absolute best I got in the JDM, about 33mpg US on a mix of fairly easy commuting and a few longer trips maxing out at maybe 65mph. Lifetime for that car was 27mpg US.

Fewer results with my UK car which I didn't own as long, but best there was 35mpg US and 28mpg lifetime (clearly when I had that car I drove a bit slower!).

Didn't make any special effort to drive economically with either of them (beyond being a naturally fairly economical driver) as they were very much both bought to have fun with, but to get over 50mpg US is impressive indeed. Your average matches the worst tank I've got from my diesel Smart...

[The Toecutter]

You could totally turn it into a targa top. Roof off for good whether, roof up for the winter and for getting the aero that is possible. Without a fixed roof section built into the car, a convertible actually offers more possibilities for a custom aero design. Throw a Miata Italia kit on the front with round tail lights in the rear and you could have this thing looking very sexy and exotic.

Originally Posted by MetroMPG

Sorry to disappoint!

But the main reason for buying this car was its lack of roof.

I realize trying to optimize a convertible for better economy is kind of like adding insulation to the walls of a room with permanently open windows. It's not ideal. But that's where I am with it.

MPGiata is coming out of hibernation this week!