34mpg :)

[DesktopDave]

I'm seeing some evidence that our systems are already r134a compatible.  I'll pick up a new dryer, o-rings & label and have a chat with my mechanic.  Here's the thread:
http://e30tech.com/forum/showthread.php?t=58110&page=3

Back to the mileage...most recent tank improved because of nearly ideal driving weather (damp, 50-60 degF, no stops, lots of trucks for drafting at >70mph).  Gasoline was also a factor...fresh truck stop 91 octane summer mix low ethanol gas.  40psi on all-season 195/14s, no A/C, windows up.  Full synthetic (5w30 engine 70w140 GB & diff) in the car.

Drumroll please...

258.3 miles on 7.381 gal (35mpg)  Just turned over 267K miles too.  The rest of the trip was less successful, around 31mpg average with more low speed driving.  Not that I'm complaining.  Does the M44 do better on mileage with its hot-wire MAF and DASC?

Garmin tells me that my rolling average over the last 12 hours of driving time was 62mph, max 89.:eek:

I'm wondering just how much more mileage I can get out of this car?  Cruise control, front air dam, splitter & spoilers?  Maybe a PS delete?  Thinner coolant?  LRR tires?  Timing advance on the cam sprockets?

[tjts1]

Data seems a little dicey on these.  I know that the possibility is remote, but pressurized flammable liquids running inches from family & self seems a little dicey.  I'm not sure that r134 would be much more expensive, just a PITA to do.  The sheer convenience of refills and reselling also makes me think R134.  Has anyone done a full retro-fit?

You already have pressurized flammable liquids running inches from family & self. Gasoline. And some of those hoses are nearing the end of their useful life after 18 years and 200k+ miles. Besides, there are millions of cars in the world running on LPG (propane) as a fuel. Usually they have 10-15 gallons in the trunk or spare tire well. I wouldn't worry about 12 contained solid metal lines.

Maybe a PS delete?  

You can pull the PS belt for highway trips. You won't notice any difference in steering effort on the highway buy it was worth 1-2mpg on my car.

[DesktopDave]

You already have pressurized flammable liquids running inches from family & self. Gasoline. And some of those hoses are nearing the end of their useful life after 18 years and 200k+ miles.

I was kidding, forgot to add the sarcasm :rolleyes:.  I'll bet my mileage will improve when I patch up with that little fuel leak off the top side of the tank.  Speaking of useful life, the BMW hoses seem to FAR outlast the generic ones.  I'll be redoing that this summer with OEM 8x13mm hose.

Used to work for a gas company, drove a nice little dual-fuel Ford Contour.  Fitted with a CNG spun carbon fiber canister @4000psi in the trunk.  Our bet was that if anything hit you hard enough to rupture that can you'd be dead enough to totally miss the fireworks.:p  My point was that servicing a Frankenstein like that isn't where I want to be.  A/C is still one of those black arts to me.

[///m42 sport]

^^ where are you getting new hoses?

[tjts1]

Our bet was that if anything hit you hard enough to rupture that can you'd be dead enough to totally miss the fireworks.:p  

LOL

I spent some quality time in Eastern europe where it seems like half the taxis and old beat up jalopys ran on LPG. Some of the systems were cobbled together with old oxygen tanks, pressure regulators etc. You could smell the propane when the engine shut off. I figured if I can survive that, 12 oz of propane in the AC won't kill me.

[DesktopDave]

^^ where are you getting new hoses?

Don't know if I was misleading...I meant new fuel line, not A/C barrier hoses.  Whatever the PO or his mechanic put on that car is cracking away.  I can still read 'BMW 8 x 13' on the OEM stuff.