316 to m42 or 320 or 325 anyone?

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B4UR
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Fri Feb 12, 2010 10:21 pm

Its just a matter of interest. I am sick of doing stupidly low miles per gallon with such a small engined vehicle. I am 19 and have a 316 touring and i do alot of motorway driving. my last trip i did 275 miles on a tank of fuel which is shocking due to the high reving at 80 mph. It is also very slow.

The car has only done 70k but if i were to find a decent donor car/ engine bits with under 100k miles is there anyone that will do it around the bournemouth area for a reasonable price or is it time to sell on and get a more economical car lol?

I am a apprentice mechanic with no garage at home and a drive i can use if i can do the job over a weekend.
Tommek
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Fri Feb 12, 2010 11:51 pm

Why don`t you try a longer geared diff? I think you will find one cheap and it will lower the revs a bit at high speeds, also improving MPG. Hope this was usefull..... Cheers
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steve_000
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Sat Feb 13, 2010 12:02 am

I get about 100miles to a tenner out my 316....

All about how your driving it, feathering the throttle stuff like that, if driving right the most economical car i had.
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JWaller360
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Sat Feb 13, 2010 4:29 am

Christ, I'm lucky to get 100 miles out of a tenner in my i.S, I put it down to mostly town driving, I can get about 90 on the motorway I'd guess, but its a LOT lower round town.

To be fair, I think the AFM isn't spot on.
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B4UR
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Sat Feb 13, 2010 12:52 pm

i have asked in the past but what would be the best diff replacement for it?
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toby
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Sat Feb 13, 2010 12:58 pm

It's probably got a 4.27:1 in there now. You could try a 3.91 or 3.64 but it will slow your acceleration somewhat. Better to try driving while watching the economy needle and only apply slow steady throttle. Try keeping it as close to 30mpg and change gear accordingly. Boring but effective usually.
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B4UR
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Sat Feb 13, 2010 1:07 pm

i usualy change gear at 2500rpm but on the motorway 80 mph is at around 4000rpm and due to a small engine carrying a big body you sometimes have to put the boot down to not slow up other traffic this is why im thinking is maybe a bigger engine a better idea? i have found a 320 not a million miles away with 79k miles complete car for 200 squid surely id spend that on a diff?
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B4UR
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Sat Feb 13, 2010 1:10 pm

saying that ive just noticed its a pre facelift so not as simple a conversion
sihooker
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Sat Feb 13, 2010 1:14 pm

You could get a 4.10 diff from a 318i. They're very common on 320i's too, and usually very cheap.
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toby
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Sat Feb 13, 2010 6:10 pm

320i is not good on economy either...

If the 316i has been well maintained and serviced, driven sensibly it can give a lot more than 275 miles a tank. It is necessary to just drive slow and accelerate gently. The crap aerodynamics of an E30 means it'll never give great economy on the motorway unfortunately.

I can get 350+ miles from my 325i touring but only if I drive it with my eye on the econometer and ignore the occasional tailgating motorist.
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mk2escort
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Sun Feb 14, 2010 12:24 pm

just a quick thought, how bout not driving at 80mph? :? i have a 2 door 316 and i've found it to be pretty reasonable on fuel, the 316 wasn't designed to go fast, so if your driving it like a 325 then it will be shit on fuel, drive it like a criuser rather than a bruiser and it'll save you loads of money, simples, :D
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B4UR
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Sun Feb 14, 2010 3:03 pm

lol thats fair enough mate maybe i need to take some weights out of my right boot
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mk2escort
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Sun Feb 14, 2010 11:13 pm

hahaha, i had that thought, i kept blaming my steel toe cap boots for my mpg, i put some trainers on and its much better now, haha :D
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