New here. BMW 323i GUZZLER. - Fuel Economy, Hypermiling, EcoModding News and Forum

pistonhead76 · 03-12-2013, 08:07 PM

Hey everyone. Im new here and obviously here for mileage help. I have a 2000 BMW 323i with the 2.5L inline 6, 5sp Trans. I love the car but have been thinking about getting rid of it or somehow better the mpg. Ive peaked 26mpg with this vehicle and average 24. Im pretty handy with wrenches and Ive built a few motors in the past. So what can I do to get better mpg? I run synthetic oil now but thats all I can think of. I definitely want to build an EV one day or DIY hybrid and would probably do it now but my work commute roundtrip is 125 miles. Fuel bill was over 400 last month. Yes, I am working on getting another job more local in which the EV would really shine. Any help for now would be appreciated.

UltArc · 03-12-2013, 08:29 PM

65+ Vehicle modifications for better fuel economy - EcoModder.com

100+ Hypermiling / ecodriving tips & tactics for better mpg - EcoModder.com

Tire pressure, followed by grille block

-While Rethinking Driving-

Then - Underbody, rear wheel wells, pizza pans, other more drastic/involved things.

MetroMPG · 03-12-2013, 10:54 PM

From: http://ecomodder.com/forum/showthrea...tml#post340337

A torquey 3 series isn't necessarily doomed to bad mpg in sub/urban driving if you maximize engine off time.

But at 120 mi. a day your options are more limited to slowing way down (search for a speed vs. mpg chart posted by the owner of that 328), significant aero mods, gearing changes ... final drive ... etc.

If you like a challenge, by all means go for it! Otherwise shopping for a better platform (which you could also mod to make even better) might be the way to go.

Moving closer to work or working closer to home kills 10 birds with one stone though.

Welcome to the forum!

AndrzejM · 03-13-2013, 04:50 PM

Hi pistonhead76! Welcome to the site! It's good to see another Beemer here

First of all you should think of any FE gauge it helps a lot. You can go for MPGuino or install (if you don't have it already) oem OBC. I've installed MPGuino in Berta and it works great. Now I know exactly when I can save or waste fuel.

Good luck with your Beemer and eco mods.

mcrews · 03-13-2013, 05:02 PM

Tires.
go up a size taller.
I went from 245/45/18 to a 245/50/18 on same rim (infiniti q45 sport)almost a 6.5% increase in diameter giving me lower rpms at cruise.
Also ran 44psi.
If you have the option also go w/ a taller rear gear.
Gotta have a mpg gauge.
see the first link in my signature SCANGAUGE.
If my 3800lb

340hp 4 door can get 30+ on the road.....so can you!!!!

ps: i always keep the climate control ON

pRoy · 03-13-2013, 05:10 PM

Welcome to the forum. Thats a great car! I have some more data since MetroMPG and I made that chart above. Over 16 tanks of gas I'm averaging exactly 24MPG. However before I put my winter tires on I had three tanks of gas around 27MPG. I had Nokian WR Low Rolling resistance tire on it for the fall just after I bought it. As soon as I put the winter tires on I could feel an immediate difference in coast speed.

My theory would be the tires made a pretty big difference. It's almost time to switch tires again and I can validate my data.

My driving is pretty much 95% rural roads. I'm not a speeder.

pistonhead76 · 03-13-2013, 06:16 PM

Thanks for all the replies and ideas!! I will keep everyone posted. I will start with the close-to-free mods first. Tire psi, areo mods, etc.

320touring · 03-14-2013, 06:56 AM

see my sig

jogfrogjog · 03-16-2013, 03:21 PM

I have a 2001 330xi. Before I was doing a lot of highway driving and there is the on board computer which displays average gas mileage. Driving 80mph I would average 25mpg. Driving 65mph I would average 30mpg according to the computer. Right now I'm averaging 21-22mpg according to the computer now. With the m54 and m52 and m50 motors that have vanos, the seals wear out which can affect the smoothness of the engine and gas mileage. This past week my water pump failed so I'm waiting on my new water pump to get it and install it and see if there's a difference in gas mileage and I had a noise which was either the water pump failing or the vanos rattle. If I still have the rattle after the water pump replacement, then I'm thinking to do the vanos seals and rattle fix and see if that makes a difference. I also switched from narrower tires to a set of wider tires so I'm thinking to move back and see if that takes care of a few issues. Also, if your CCV needs to be replaced, you might be burning more oil than you realize which would also likely lower your engine's efficiency requiring you to burn more fuel to get the same level of power.

I'm also planning to put underdrive pulleys on the water pump and power steering that I'm picking up used to see if I can get better gas mileage with the price of gas going so high recently.

Generally, engine maintenance is a good idea to keep up, so check spark plugs and coil packs, air filter, fuel filter, etc. Also check your final drive ratio, for my car, for the manual tranny, it's a 3.07 ratio, for the auto for the same car it's 3.46.

jogfrogjog · 03-16-2013, 03:31 PM

Also, if you're into modding and thinking of doing a grill block, it's not a bad idea to over build the cooling system. Stewart water pumps are 20% more efficient than the oem bmw water pump and run cooler and there might be a lower temp thermostat that you can use for it to open up at a lower temp. The e46 and e39 engine cooling systems are generally notorious for failing at close to 60k miles so running it at a cooler temp will let less pressure build up on the system and theoretically help it last longer. You can also get an all aluminum racing radiator and if you have a mechanical fan, replacing it and putting an electric fan can free up some hp used to turn that over. Also adding a light weight flywheel will help with performance as well as engine efficiency again freeing up hp used to move mass.