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

[rlee94]

Originally Posted by freebeard

With a proper 7° curve and fences you could have a Magic Butt Trumpet

That looks amazing. What about lights, though? No turns or brakes that I see.

[MetroMPG]

I borrowed that tonneau cover from a Miata-owning friend this summer with the intention of tuft testing it to see how it affects airflow.

Although I used it regularly, I never quite got around to doing the test.

But I'm pretty confident it helps somewhat, just based on the fact that there's noticeably less wind noise with the tonneau on than off.

With the tonneau off, these open areas at the sides seem to be where the wind noise is coming from:





I'd still like to tuft it, though. I haven't found any info about the aero effectiveness of the Miata in several searches. It'd be nice to contribute some new info to the Miata world.

But I'm about to quit driving the car for this year. MPG on the current tank is beginning to suffer from the colder weather - it's around 47 near the 3/4 mark.

[MetroMPG]

The MPGiata has been retired for the winter!

There was nothing in the extended forecast that looked top-down friendly, and we've already had a few light snowfalls. (One of which needed shoveling; since melted).

The car turns 30 years old next spring. For its birthday present, I'm aiming to get a 55 mpg tank next year. Needs more mods!

[pete c]

I've had an '18 RF for a few weeks now as a rental. Here are a few observations.

I don't fit.

This was obviously designed by a 5'4" 110 lb Japanese dude. Were I such a person, I would consider it. If Mazda stretched it 3 inches in length and 2 inches width, I believe they's sell more.

If I did fit and were to buy one, I would never get the RF. The top takes for ever to go up/down. And I suspect you give up a few inches of precious seat travel. And it adds about 130 lbs, which is huge for such a light car. The ragtop goes up and down effortlessly and can be done at speed. The RF's roof mechanism will not operate above 6 mph.

Rather than the folding top, which really isn't. It is just a folding targa top, they should have done a hatchback with a removable targa top. This car should basically be a 1st gen RX-7 with a 4 cylinder.

Styling wise, they tried to follow the current sharp nosed theme. What they ended up with is a 3/4 scale 70s Stingray. I preferred the earlier generations modeled off old MGs.

It still is the absolute state of the art fast, slow car. This thing carves turns like nothing I have ever driven. Tail out slow twisties are an absolute blast.

Mileage is impressive. 37-38 mpg can be had with a healthy dose of silly driving. Any attempt at conservative driving gets it into the 40s. This is with the slushbox. Drive it like a total douchebag and you are still gonna get to 30. I think you'd have to flog it mercilessly with the e-brake dragging to drop into the 20s.

Give this thing a nice slick hatchback, stop trying to make it look like a 74 stingray front end and with a 6 speed manual and I think it could get to 50 mpg easily. Drop it down to about 1.2 liters and it would do 55-60. And it would still be fun to drive. At 2 liters, it is on the verge of being a fast car. And this is an 18. The 19 revs freer and is good for nearly 20 more hp.

[MetroMPG]

Originally Posted by pete c

I've had an '18 RF for a few weeks now as a rental.

A rental?? Interesting. Holiday car?

Mileage is impressive. 37-38 mpg can be had with a healthy dose of silly driving. Any attempt at conservative driving gets it into the 40s. This is with the slushbox.

That IS impressive!

It's kinda disappointing to have to put so much effort (driving) and mods into squeaking 50 from mine when you could probably get very close to 50 from a brand new bone stock manual.


I am half-tempted to ask Mazda Canada if they would consider loaning me one from their press fleet to write about here.

[Ecky]

My guess is the 4G Miata would probably do considerably better even, if it had a properly tall last gear.

[Gasoline Fumes]

Originally Posted by MetroMPG

I am half-tempted to ask Mazda Canada if they would consider loaning me one from their press fleet to write about here.

Do it!

[oldtamiyaphile]

Originally Posted by MetroMPG

It's kinda disappointing to have to put so much effort (driving) and mods into squeaking 50 from mine when you could probably get very close to 50 from a brand new bone stock manual.


I am half-tempted to ask Mazda Canada if they would consider loaning me one from their press fleet to write about here.

Do it x2

I really should have an RF in my little fleet. The only issue is that while at 6' the driver seat is fine, the passenger seat is more limited and that would make longer drives with driver swaps a bit of a pain. Might still be worth it.

[Ecky]

Originally Posted by oldtamiyaphile

Do it x2

I really should have an RF in my little fleet. The only issue is that while at 6' the driver seat is fine, the passenger seat is more limited and that would make longer drives with driver swaps a bit of a pain. Might still be worth it.

Luckily only 9% of American adults are 6' or taller. Factor in children and it's a very small number of people who are affected.

All joking aside, I fit very comfortably in a Miata of any vintage.

[Gasoline Fumes]

Originally Posted by Ecky

Luckily only 9% of American adults are 6' or taller. Factor in children and it's a very small number of people who are affected.

All joking aside, I fit very comfortably in a Miata of any vintage.

I'm 6'-3" and I barely fit in a Miata. I do not fit in a Kei truck, I've tried. And I sat in a Lotus once (Elise? Exige?) and the the top bar of the windshield was in front of my eyes. I'd have the look over the windshield to drive! Being tall and liking small cars is tough!