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

[Xist]

Originally Posted by MetroMPG

Anybody remember EM member kroushdb? He had a Civic VX in the pre-MPGuino days, and used a digital multimeter to note the resistance of his tank fuel gauge sender, which he would plot against his trip odometer at the end of each day's commute!

Can you think of a way to make a gauge out of that?

I did pulse and glide with my first car, but I called it "leapfrogging." I stopped after a while because I could not measure a difference.

[Piotrsko]

Originally Posted by Xist

Can you think of a way to make a gauge out of that

Yes but the float system is so inherently inaccurate, I cant see reasons to use the data for precise estimates. You could use a flow sensor if you dont return fuel to the tank.

[MetroMPG]

Dan's approach with the float system was to only take readings when parked in his usual parking spots at work and at home. Obviously it's useless to monitor live readings while moving, or even if the car is parked on different grades.

[MetroMPG]

Someone gave me these. Will they help me save fuel?





The weather has turned - we've had some cool days & even cooler nights recently (I could see my breath this morning).


Result: 50 MPG is out of reach, driving at the speeds I was in July & August.



Also, I'm wondering if the t-stat may be stuck open. It takes forever to warm up, and never quite seems to get to full operating temp on cool mornings/evenings.

[kurzer]

Date: 15.05.2009 km: 230.100 Prize: 20€ spare part: thermostat

this is not unusual, a not perfekt closing thermostat.

[MetroMPG]

When I got the car, the top leaked quite a bit in heavy rain. It's the reason the floors were rusted out - frequently wet carpets.

I made a cover for it out of some used boat shrink wrap :




There are some cracks in the vinyl where it folds, but I discovered most of the water was coming through the stitching along various seams. So this summer, I spent some time carefully taping & applying a bead of black silicone over the stitching.

Now the only place it leaks is around the weatherstripping above the driver's window. Current solution!

[Piotrsko]

Window weather stripping is cheap from a bunch of aftermarket suppliers, like maybe $14 a door, or it was for the Ranger.

I do like the umbrella, but it looks impractical for highway driving.

[MetroMPG]

Also impractical for, you know, being able to see things! I could get one of those clear umbrellas.

I have to look into the source of the leak a bit more - I'm not 100% sure it's the weatherstripping itself. Luckily, I haven't been caught in prolonged rain while actually driving. Most of the time the car sits parked. If I use it a couple of times a week, that's a lot.


===


I'm coming up to what might be the last fill of the year. I'll be surprised if I crack 50 MPG on this tank.

Anecdotal headlights observation... with these open:



I could only get ~46 MPG on a warm evening drive where I'd normally see ~50. With the top down, I could definitely feel & hear the change in airflow with them popped up. Obviously a flush mount headlight is better for aero... but gosh darn, it's so cute with the big eyes open. Surprised frog!

[Xist]

With my first car, a 1987 Prelude Si, I wondered about making customary stationary headlights, but the law would have liked to talk to me.

[freebeard]