making 325 bit more eco...

[bmw9818]

recently did a swap, refurbed injectors new gaskets, full service all new parts etc....

on £55 gauge down and obc blank to same, i did 180 miles of town driving, caning the shit out of it 25% and eco most of the time, that about right...?!

any other ways to get a bit more mpg out of it with the exeption of driving like a granny?

its a daily and im broke so no other car

[Andros]

That's poor mileage realy but expected if ur flooring it often it easy done with powerful engine though

[Brianmoooore]

Assuming it's all running properly, there's only one way to make a 325i more economical, and still drive it as it's meant to be driven, and that's to convert it to run on LPG.

[suchy]

M20B25 + fuel economy will never go together in a sentence

Put up with it or LPG or Mxx swap or if you do a decent number of miles it's cheaper to run a small economical cheap run-around also!!!!

[reggid]

a higher CR stroker with very mild cam will get better economy than a stock B25 unless of course you are lead footed

[sunnyr83]

Any performance loss when LPG is installed?

[Brianmoooore]

Small loss if you fit the simpler single point mixer ring type system, compared to a petrol system in perfect condition, and if you make no engine modifications towards optimising performance on LPG, but in practice ,nothing really noticeable.
No loss whatsoever if you fit a multi point injection system, and the potential for increased performance if you take advantage of LPG's 100+ RON.

[George]

Pump up the tyres a touch more.

I typically get 300 miles from a full tank until the low fuel light comes on.

[Speedtouch]

A mild chip can help yield an extra 2-3 mpg on average.

[kangman]

Go 4pot...

[stu328is]

I'm still amazed how far i can drive from the empty marker to when the light comes on on the e30, how many miles is it supposed to give you?

In my E36 2.8 as soon as it hits the quarter mark i know i'm going to be getting petrol v soon

I've got to know the petrol station guy rather well running the pair of them

[bmw9818]

yeah dont think il be doing an m50 swap recently spent 4k on doing the car up and swapping in an m20! i might look into lpg but probably get it done professionally...

speedtouch - will be in touch in the new year or on pay day end of the month! was looking into the mild chip for a little while,

[polsta]

i used my 325i as a daily for a bit last year- 50 mile round trip to work, town-motorway-town, and back

experimented a little with fuel/driving over a period of time, i then invented a fuel game, drove 1 mile to motorway, got on that then kept foot rock solid didnt move it keeping the mpg gauge thing over 30 , that was the rule of the game, then let it go with the natural flow of the motorway layout... the speeds ranged from 40mph at 1 point uphill to 85mph going down hill (not steep) , all the time my foot not budging, so no foot increase/decrease on the gas at all, although sometimes when it picked up speed going down hill i let off the gas bringing the mpg line up a bit tot he 40mpg line

was funny...youd get overtaken on inclines by trucks etc going at 45-40 on the steepest bit, then gradualy speed up again and a few mins later overtake the truck doing 70/80, and youve not accelerated on the gas at all !!! was funny as f**k !!!!

then back through the town did the same as muich as possible (ie traffic lights etc) but as mush as possible would keep that mpg line above the 30 and try drive generaly without breaking much or hard accelerating, just a nice smooth economical drive

the difference in the same drive, but driving how you wanted to drive having some fun and giving it a bit etc driving with a smile on your face, , would be almost double in fuel costs

[bmw9818]

lol yeah i tried that the other day, but just coudnt take being overtaken by 3pot bluemotions and "bad boy ripspeed astras" on the a3, so i switched it to 3rd and floored it! i was eco driving for about an hour, and then fucked it up!

had a big ass smile on my face when it roared up to 6k though!

[Brianmoooore]

the difference in the same drive, but driving how you wanted to drive having some fun and giving it a bit etc driving with a smile on your face, , would be almost double in fuel costs

Or, powered by propane, you have have the cost of the economy run with the "smile on your face" driving style!

[polsta]

it might become an option brian, i do agree !! but got to get the car how i want it and all finished beofre thinking about that, if its installed and removed- what trace/damage is left to originality ? many holes etc ? would it have any effects on anything afterwards being removed ?

[bmw9818]

I read up that you need to drill holes in the inlet manifold for the LPG injectors, so assume intake manifold would need replacement if going back to oem...

[Brianmoooore]

There are no engine mods. whatsoever for a mixer ring venturi system. The only mod. is to modify the bracket for the air filter to move it forwards about 20mm.
A vapour injection system requires M6 holes to be drilled in each port of the inlet manifold, but these can be blocked with short 6mm bolts.
The cheapest way to but a decent LPG kit is to buy a cheap car with a kit on, remove the kit and sell it on. A couple of years ago we bought a Mitsubishi estate with a 6 pot engine for £99, removed the OMVL injection kit (blocking the manifold with 6mm bolts) and sold it on, and I recently liberated a Stag four pot injection kit from a Rover 45 that was 'passing through', which is going onto the E30 cab. that's currently under restoration in the workshop.

[FinalD]

M20B25 + fuel economy will never go together in a sentence

Oh I dunno...

The M20B25 has piss poor fuel economy.

[suchy]

M20B25 + fuel economy will never go together POSITIVELY in a sentence

Oh I dunno...

The M20B25 has pee pee poor fuel economy.

efa

[polsta]

There are no engine mods. whatsoever for a mixer ring venturi system. The only mod. is to modify the bracket for the air filter to move it forwards about 20mm.
A vapour injection system requires M6 holes to be drilled in each port of the inlet manifold, but these can be blocked with short 6mm bolts.
The cheapest way to but a decent LPG kit is to buy a cheap car with a kit on, remove the kit and sell it on. A couple of years ago we bought a Mitsubishi estate with a 6 pot engine for £99, removed the OMVL injection kit (blocking the manifold with 6mm bolts) and sold it on, and I recently liberated a Stag four pot injection kit from a Rover 45 that was 'passing through', which is going onto the E30 cab. that's currently under restoration in the workshop.

so what do you look out for when looking for a cheap lpg car ? just a working 6 pot lpg car ? any 6 pot ? does it have to be 6 pot ? any chance of a little guide on what to look for and maybe a list of contenders, id like to look out for a kit and just get my hands on one and put away in the garage

[Morat]

Any six (or eight) pot car should do it, but you'll want to check out the size of the tank pretty carefully to be sure it fits in the spare wheel well of an E30. LPG tanks over ten years old need to be re-certified and then only last IIRC another five years after that. You may well end up buying a new tank anyway.
Tinley Tech have a good list.

[Brianmoooore]

I don't worry too much about the tank when I buy a car to free it of its gas kit, although if it is of a usable size it's a nice bonus. A new tank of the size you need isn't that great an outlay.
More important, if you want to use the kit on a different engine, is that the kit is one that you can get the software and laptop interface for, and, if you want to sell the car on, it helps if the filler has been fitted somewhere where the hole can easily be filled, such as on a tow bar, or low down on a bumper.
As Morat says, 6 pot and 8 pot stuff is usually the same, but if you're looking for a kit for a 4 pot, then it will have to come from a 4 pot.
Another thing that helps when buying a LPG car is if that car is faulty, and you're confident that you know what the problem is and can fix it for minimal outlay.
An example is an E36 325 with a Prins VSI kit that I have - this is top of the range stuff, and goes new for about £1700 fitted.
This car was local to me, had been sold for £1000 and had been returned to the seller for "having a blown head gasket".
It was then up for sale for £600 with the said "blown head gasket" (Seller's words, not mine.)
If you know your Prins VSI kits, you'd know that the original design of the vaporiser was prone to an internal gasket failure that allowed propane at up to 200 PSI to leak into the cars cooling system, blowing out the coolant, not unlike a failed head gasket does.
£600 handed over, one £22 Prins gasket set later, plus a couple of hours fitting and some fresh coolant, and I'm the owner of a pristine E36 325 with the Rolls Royce of LPG kits, which served my wife well for four years after the demise of her red E30 touring.

[Speedtouch]

If only we all had your encyclopedic knowledge of propane kits, Brian!