My S13 - Project uglification (1993 Nissan 240sx hatchback)

[vrmilionzx]

Mileage update: filled up this morning, and doing nothing but modifying my driving habits, I'm up to 28.9mpg. I'm not sure if I should be happy, or frustrated - it was about 50/50 hwy and city, and a good deal of the highway had traffic issues. I also ran the A/C on about 10% of that hwy driving, maybe more.

So without the traffic, I feel confident that I can break 30mpg mixed. I'd love to see what I can get just on the highway, but I don't have any trips planned for the next couple of weeks, and since the goal is to save money/gas, I'm having a hard time justifying taking a trip just to see.

[Lincoln]

Two questions:
1) what is your tire pressure set at?
2) When you changed your rear gear ratio, did you correct your speedometer?

[vrmilionzx]

Tire pressure is at about 44psi, and that measure takes into account the change on the speedo (about 3% - I factored that in. The actual mileage was 306.8, which i multiplied by 97% to adjust for the longer gearing).
So to answer #2, no, i didn't correct the speedo, i factor it out after

[Jbuttenshaw]

Keep the updates coming! I have a 180sx and while I'm not planning on going Eco mod nuts I do like the idea of efficient commuting so I'd like to see how you go/what makes a difference on these cars. Any chance you can post some pics of the electric steering? Sounds interesting. Which mr2 is the pump from? W30?

[MetroMPG]

I'd be interested in a summary thread about your power steering pump swap also - would be good to add to our list of mods (I'm not sure we've got that one up there yet). A separate thread would be ideal.

[Sporty Modder]

Any Updates?

[vrmilionzx]

No new updates yet - I'm looking for the info I've got on the PS mod, so I can open a separate thread. Other than that, just driving, and trying to normalize my driving before adding anything to the car, so I can get a good solid measure of the (hopeful) improvements by mod. I'm also thinking on how I'd like to do a couple of them.

Although I suppose that using 0.0 gallons today because I'm riding my bike to work on Mondays and Wednesdays is a bit of an update. Not increasing the mpg, but decreasing total fuel consumption for the week.

Thanks JButtenshaw! In terms of the PS pump, I'm not sure on the chassis codes for MR2's, but it was the 92-94? model, second gen. Actually, you can kind of see the ps pump on the right side of the pic (driver's side) of the engine bay. I'll see if I can get a better pic for you a little later. You're one step closer than I am to awesome mileage, because yours should have the ca18, right? smaller motor could definitely mean better mileage.

[Jbuttenshaw]

I see this thread has been stagnant for a while but I'll post anyway. I've recently removed my power steering completely as a hose split. I also took the mud guards off. The best I have done is 8.2L/100km most recently I did 9.1. Way off your best at nearly 6L/100km! How much have you changed your driving? Have you got any figures for the benefits of folding the mirrors? How did you pick your 62mph speed?

Cheers

[vrmilionzx]

Hey, bringing the thread back to life!!!

Unfortunately, the best I have in terms of benefits from folding the mirrors in is the estimate in my first post, somewhere from 1 - 1.5mpg. This is a VERY rough estimate, because the measures were taken on two separate trips, a week apart. This kept the route similar, but traffic may have varied slightly, and temp could have been different. I used a longer trip to try to "normalize" smaller changes out, but outside of that, there was not much in the way of minimizing other variables.

I've changed my driving quite a lot, actually. I've moved my shifting points (usually shift by 2200 rpms, 2500 uphill), and I try to keep it under 2500 pretty much everywhere. This means slower acceleration outside of first and second gear. I'm also trying to coast more, and time the lights better. I've been driving exclusively with in gear and clutch in coasting as opposed to EOC, as the car seems to behave a little strangely when i get the motor running again, and I think it might be dumping some fuel initially when I start it back up (whether I clutch bump it or use the key). I want to evaluate whether EOC is triggering the issue that makes it idle funny, and suck extra fuel. I've reduced my brake usage, and in general been driving a little more slowly. The lightened flywheel probably helps in traffic, so some of my gains might come from that. The other key change I've made is exploring and mapping. I've been altering my route to allow me to go further without stopping. 2x a week I drive about 25 miles in dreaded Los Angeles traffic to a class I'm taking. I've begun taking exclusively surface streets rather than the highway, as the highway is just about gridlocked. Surface streets were initially an experiment, and it took almost exactly the same amount of time. I felt much less angry when I arrived, though, because I felt like I was moving more consistently. Try altering your route for less stopping, if you can.

62mph.....no, I don't remember how I chose 62. I think it might have been keeping the speed similar to what I drove the previous week for mirror testing. The other possibility is that I was trying different RPM points (rather than speed - that was when I still thought my speedo was off; turns out it's almost dead on). I usually keep it to ~57 mph now, and that's just because going above that takes me over 2500 rpms.

I've also been a terrible slacker, and while I've drawn lots of pictures, and gathered several of the parts/materials, I've not actually done anything else to mod the car, other than a small undertray...

Tell me more about your car - miles, mods, driving habits, etc. I'm really curious about the 180's diffferences from the 240 (obviously the motor is the biggest, but what's the gearing? Does it have the same trans/gear ratio as the silvia/sr20 version of the car? things like that).

[Jbuttenshaw]

My car; it has 195000km on it... Performance type mods are 3" exhaust, s15 intercooler, lightened flywheel, konis and king springs. I've removed some basic stuff to save weight without making it too obvious: rear wiper and motor, rear speakers, power steering, mud guards, rear wheel steering and lines (hicas) and its got lighter wheels on it. I bought it and like to use it as a sports car so fuel economy is secondary but I got hooked when I realised how much you can improve without modifying the car significantly. My car weighs 1190 standard, I believe it has the same gearbox as the sr20 but a higher diff ratio at 4.11.

After reading the driving tips on this site again last night I noticed that I naturally drive fairly inefficiently so I was trying to rectify that today. I mainly target efficiency on long highway drives and mainly just by trying to stick to a reasonable speed. I was aiming for 108km/h when I got my best, 8L/100km, which I thought was getting to the maximum but now I'm going to have to try some different tactics. My theory for 108km/h was to sit at peak torque but after thinking about it today that figure it as WOT. Peak torque at half throttle for example will be lower I think. I guess I'll just try going slower and see what happens. Below 3000 rpm in my car is pretty bad as it doesn't make must boost there.

28 mpg is very impressive for an early 90's sports car, yet another reason the ft 86 is nothing special...