325i Sport MPG ?

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dynoo
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Sat Mar 20, 2010 10:54 pm

Hello guys, new to the site and it looks to be good steam...

Just wondering what sort of MPG any of you's are getting with the M20
I can just about scrape 25mpg on a long journey with a really light foot, proper cruising

If i push it on tho that drops big time down to 10-15mpg average :mad:

I seen a thread on a diff forum tho and guys wer saying that they wer getting 25mpg , but that was with hard driving !

Someone said i can get my injectors cleaned ultrasoncially and there was a guy on here that does a chip for them by the name of speedtouch, who had good reviews..

Atm its being used as an everyday car untill i get the wee derv back on the road, and its breaking my heart tbh lol.
Trying the resist that sick 6pot note
Then fuel needle sits and waves at ya fs , its like :wave: BOUT YEE :wave:

Just wondering what your thoughts on the subject are guys and if anyone can shed any light ???

The only downfall of the car tbh !

Few pics of it

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Cheers


...
jbh
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Sat Mar 20, 2010 11:00 pm

I used to get around 30 out of my tech 1 and I wouldnt say I was taking my time with it but wasn't driving it like a nutter.. try giving it a good service and its worth a bash putting a chip in it from speedtouch. I would also check the blue temp sensor to see if the ecu is maybe getting false signals and cousin the car to run rich
bss325i
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Sat Mar 20, 2010 11:12 pm

My '89 325i Sport has only done 58000 miles and is in perfect condition with the only engine mod being a 6 branch.

The best i have ever seen on the OBC is 26.9mpg and that was driving like a granny and using the cruise.

Driving a bit more lively and around town drops it to about 20mpg.

M20's are a 20 year old 6 pot, they aint gonna be very frugal.
kieran325
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Sat Mar 20, 2010 11:16 pm

I run a 325, full BTB system and a few weeks ago I did 200 miles on half a tank of V Power, done another 110 since and its on the quarter mark, not bad MPG but I didn't work it out :o:
Nay
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Sat Mar 20, 2010 11:17 pm

Those 17" pina's are your problem :lol:


A mild chip from speedtouch could give you a slightly improved mpg, but dont expect anything. It will/should make you car a little more responsive and give a nicer feel to drive. Worth it for £30 or whatever.

Whats the milage? Power and engine management/cleanliness is won and lost in the cylinder head. It could be begining to loosen up or get a bit bunged up and dropping your mpg and bhp a bit.

TBH though, 325i's drink. 320i's drink just as much for much less grunt. If you can hit around the 30 mark for a cruise, your doing ok. Otherwise, 10-15 when booting it.


Try an E34 535i..... just a touch of throttle and the eco-meter just swings off the radar completely. Best I got realistically was 10-15mpg average! :mad:
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dynoo
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Sat Mar 20, 2010 11:31 pm

jbh wrote:I used to get around 30 out of my tech 1 and I wouldnt say I was taking my time with it but wasn't driving it like a nutter..
Thats the ticket

The car is fully serviced oil, filter wise, i just had to take the fellas word that the plugs wer done.
Maybe i shud change them just incase.
I got the emissions set and done the valve clearances aswell in a bid for better economy.

Just wondering if anything cud be done, but at the end of the day
Its worth it

Shes a 91 with 116k FSH on it.

And jesus , 10-15 average , thats wild lol


The guy who had it before me had it on 15's .. Well cool

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Nay
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Sat Mar 20, 2010 11:33 pm

Looks like RS's.

Nice car.

Yea mpg aint good, but the sound is addictive :D
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bss325i
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Sat Mar 20, 2010 11:35 pm

I remember that car, Granite silver.

Looked awsome on the BBS RM's.
http://www.bmrperformance.co.uk

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kam-325i
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Sat Mar 20, 2010 11:39 pm

10-15 is crap, i get around 20-24 around town in mine....pushing 30+ on the motorways...
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jbh
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Sat Mar 20, 2010 11:40 pm

bss325i wrote:My '89 325i Sport has only done 58000 miles and is in perfect condition with the only engine mod being a 6 branch.

The best i have ever seen on the OBC is 26.9mpg and that was driving like a granny and using the cruise.
Im suprised at that Barry. I didint find the tech 1 that bad on fuel TBH mines had 133k but engine had been fully rebuilt at 105 due to cambelt failuire.. loads of paper work to prove from the dealer that this had been done by BMW. just a pity the car spent most of its life in orkney :cry: the shell was one of the worst id seen once I started digging into it.. still got the engine but in 2 minds to go 2.7 or put this in..
Nay
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Sat Mar 20, 2010 11:43 pm

kam-325i wrote:10-15 is crap, i get around 20-24 around town in mine....pushing 30+ on the motorways...
I get that in my 320i and 325i. My E34 was the drinker.

Dont have motorways in jersey, so couldn't give a real cruising figure.
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Speedtouch
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Sat Mar 20, 2010 11:43 pm

I can indeed supply you a Mild chip which should improve the fuel economy (by up to 10% according to one recent Zone customer) - see http://www.e30zone.net/modules.php?name ... 6&start=75

The average on a stock M20 should be around 25-26mpg, which is what I used to get out of mine, although a later low compression Tech 2 Sport only returned low 20s mpg and that was with Megasquirt and no restrictive AFM! I used to see low 20s mpg out of an E34 535iSE (manual gearbox), and up to 30mpg on a long motorway cruise, so there's no good reason for an M20B25 to be poor if in good tune.
///M aurice
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Nay
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Sat Mar 20, 2010 11:46 pm

Thats exactly the same figures as mine! 535i manual. Low 20s when grannying, nothing when gunning.


Could the high/low compression differences between pre and post facelift engines (M20's) cause mpg differences?
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jbh
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Sat Mar 20, 2010 11:49 pm

Nay wrote:

Could the high/low compression differences between pre and post facelift engines (M20's) cause mpg differences?
could also be the ratio in the diff tech1 is 3.64 where as the tech2 is 3.91 but would be interesting to find out if theres a big difference
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LagunaE30
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Sat Mar 20, 2010 11:52 pm

how do you guys get 20mpg the best iver ever got is 18mpg and that was after a service its pissing me right off as im a student and moneys tight and most of the time the e30 struggles to get past 15mpg around town..
is there anything i should be looking out for, temp sensor maybe as i can sometimes smell the car running rich and idle tends to rise to 1500rpm and then drop back to 1000 every now and then, could this temp sensor be the problem and how do i go about fixing it?
Nay
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Sat Mar 20, 2010 11:52 pm

jbh wrote:
Nay wrote:

Could the high/low compression differences between pre and post facelift engines (M20's) cause mpg differences?
could also be the ratio in the diff tech1 is 3.64 where as the tech2 is 3.91 but would be interesting to find out if theres a big difference
I'd like to know.

I have a facelift with a pre facelift engine. If the earlier high comp engine is better on the MPG (especially after my work!) then I'll be rather chuffed!
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jbh
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Sat Mar 20, 2010 11:55 pm

LagunaE30 wrote:how do you guys get 20mpg the best iver ever got is 18mpg and that was after a service its pissing me right off as im a student and moneys tight and most of the time the e30 struggles to get past 15mpg around town..
is there anything i should be looking out for, temp sensor maybe as i can sometimes smell the car running rich and idle tends to rise to 1500rpm and then drop back to 1000 every now and then, could this temp sensor be the problem and how do i go about fixing it?
could be the blue temp sensor if you do a search mr Morre has stated plenty of times how to check this. but could be worth checking
Speedtouch
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Sun Mar 21, 2010 12:05 am

The earlier 25 6E high compression in my 1988 325iSE was noticeably better on fuel and performance than the 25 6K low comp in my 1989 325i Sport, though the 325iSE had a 3.64 diff and the Sport a 3.91

So yes, I'd say the high compression engine makes quite a significant difference.
///M aurice
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Blitz
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Sun Mar 21, 2010 12:11 am

God I hope I dont go bankrupt when I start running a 325i cabby. The problem is you will want to floor it just to hear the engine. :cry:
bpowell555
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Sun Mar 21, 2010 12:37 am

Have just fitted new voltage regulator to mine and will see if that boosts mpg. Everything else is sweet but probably getting 24-25mpg on mixed driving. Not really gone for a cruise though .... I'm hoping 26-27mpg but don't hold out any hope of ever seeing 30 over a tank lol. Its the two valve heads, lack of air is offset with more fuel. 4 valve heads get an instance 10-20% more mpgs.
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Nay
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Sun Mar 21, 2010 1:12 am

LagunaE30 wrote:how do you guys get 20mpg the best iver ever got is 18mpg and that was after a service its pissing me right off as im a student and moneys tight and most of the time the e30 struggles to get past 15mpg around town..
is there anything i should be looking out for, temp sensor maybe as i can sometimes smell the car running rich and idle tends to rise to 1500rpm and then drop back to 1000 every now and then, could this temp sensor be the problem and how do i go about fixing it?
That is bad!

Shouldn't an m20 idle closer the the 600rpm mark?

Cant wait to see the effects of a rebuilt cylinder head on mine :P
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m42sport
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Sun Mar 21, 2010 4:44 am

I got 32mpg on highway. All synthetic. engine, tranny, diff. diff is 4.10 lsd. Trip was measured gas tank to gas tank. pressure in tires 34. avg speed 65-70. I also have a oem sump guard. Maybe that evens out airflow on the undercarriage?
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Nay
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Sun Mar 21, 2010 3:58 pm

Is that an M42 though?
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m42sport
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Sun Mar 21, 2010 4:31 pm

no with my 325i. I got a little more with my m42. 33mpg.
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HairyScreech
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Sun Mar 21, 2010 5:13 pm

if you not seeing 28-35mpg out of town then somthing is wrong with either the car or your driving style, as iv said recently in the 4 pot thread i had 28mpg at a 78lepton average speed, thats a lot of booting it.
and 32mpg over 120miles mixed extra urban driving.
i still get about 24mpg rolling around town if im gentle.

things to check in order of ease of rectification.

air filter
oil
blue temp sensor
plugs
distrobutor cap and leads
injectors
inlet gaskets
compression

if any of them are fecked then expect mpg to droop like and impotent fat man.
my blue temp sensor went a few weeks ago, i lost 8mpg for the sake of £9 :mad:
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Baz666
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Sun Mar 21, 2010 6:24 pm

i`v just had all the above done on my m20 my engine is running really smooth now took it on its first run the other sunday and got 458 miles out of £50 worth of fuel which i`v never had before, what that gives me in mpg i dont know ??
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HairyScreech
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Sun Mar 21, 2010 6:38 pm

at current prices something like 45mpg!










but dont trust my maths, i dont. :roll:
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m3.3.1 m20 thread - now running, chip needed - any volunteers?
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Baz666
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Sun Mar 21, 2010 6:55 pm

that's not bad then, because at one point of the journey speaking to Rav on the phone i booted it and was doing 120 mph but the rest was around 65/75 all the way there.
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HairyScreech
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Sun Mar 21, 2010 7:12 pm

100% motorway?
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
bss325i
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Sun Mar 21, 2010 7:17 pm

HairyScreech wrote:if you not seeing 28-35mpg out of town then somthing is wrong with either the car or your driving style, as iv said recently in the 4 pot thread i had 28mpg at a 78lepton average speed, thats a lot of booting it.
and 32mpg over 120miles mixed extra urban driving.
i still get about 24mpg rolling around town if im gentle.

things to check in order of ease of rectification.

air filter
oil
blue temp sensor
plugs
distrobutor cap and leads
injectors
inlet gaskets
compression

if any of them are fecked then expect mpg to droop like and impotent fat man.
my blue temp sensor went a few weeks ago, i lost 8mpg for the sake of £9 :mad:
I can say for 100% sure that all of those listed above are fine on my 325i but as i said, the best i have ever seen was 26.9mpg on the OBC cruising at approx 50-60mph using the cruise control.

How accurate the OBC is i dont know but thats what i have got.
B7
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Sun Mar 21, 2010 7:19 pm

Everyone gets better economy than Barry. He drives like a loon :wink:
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god-father88
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Sun Mar 21, 2010 8:05 pm

i got 31ish from my 325i sport!. last i took it for a normal town driving spin was 31.6mpg! and i was drifting out in practically every corner! :D i coast alot aswell!..when i brought it the OBC has 18mpg on it! i think it depends on how you drive & condition of your engine! :P
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dynoo
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Sun Mar 21, 2010 9:24 pm

HairyScreech wrote:
things to check in order of ease of rectification.

air filter
oil
blue temp sensor
plugs
distrobutor cap and leads
injectors
inlet gaskets
compression

if any of them are fecked then expect mpg to droop like and impotent fat man.
my blue temp sensor went a few weeks ago, i lost 8mpg for the sake of £9 :mad:

Yea got a new Power Tec induction kit
Fresh oil
Checked plugs and gaps when doing valve clearances

Thinking of getting my injectors cleaned, defo see a return on 20yr old items i wouldve thought

I see people are saying about testing the blue temp sensor, ive searched for how to do that but cant really find anything.
Would anyone have a link handy on how to do this ?

How long roughly did yours take to warm up with a doggy sensor?
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m42sport
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Sun Dec 26, 2010 3:15 am

anyone got pics on how to replace the fuel injectors?
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Simon13
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Sun Dec 26, 2010 11:21 am

i used to average about 23-24 in my old sport. with a 3.91 diff you'll never get good mpg figures when cruising unless you do 55mph!
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