323 to 325 upgrade

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poolnoodle
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Location: Hobart, Tasmania, Australia

Thu Oct 15, 2009 1:26 am

G'day all,
After test driving a 325 last weekend I feel the need to give my M20B23 Jetronc the flick in favour of a M20B25 Motronic winkeye

Can anyone point me in the direction of some useful information for carrying out this conversion.
TIA
'83 Bronzit 323i (mmmm, chrome)
'74 Polaris 2002 (mmmm, retro)
'89 Delphin 535i (mmmm, waft waft)
zaust
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Thu Oct 15, 2009 8:25 am

Do the electric side of thing's first. If you run your b23 on the later 1.3 motronic set up, you will proberly find there is un-noticable difference between the two engines.
M30 Tech 1 Touring on gas.
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djk
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Thu Oct 15, 2009 12:28 pm

It's not much more effort to plonk your head onto a 2.7 eta is it? The etas seem to be reasonably plentiful in Oz from what I read on here. You should end up with 325i power and more torque with that set up, though maybe a 325i inlet/TB would be required - not difficult.
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"doughnuts - power braking in circles" Peterborough Evening Telegraph :chuckle:
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mark_i
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Thu Oct 15, 2009 1:30 pm

an M20B25 got listed on the 'Bay this morning...

happy to check it out if you want.
poolnoodle
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Thu Oct 15, 2009 10:12 pm

I'm thinking of a complete donor 325 - even have one lined up. Just wondering what is needed, ie. gearbox, exhaust, etc that needs alteration
'83 Bronzit 323i (mmmm, chrome)
'74 Polaris 2002 (mmmm, retro)
'89 Delphin 535i (mmmm, waft waft)
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mark_i
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Thu Oct 15, 2009 10:53 pm

as always, you have to decide how far to go.
A full blown 325i convo would need the engine and the Motronic 1.3 electrics, loom and ECU.
Grab the exhaust too. (i'll take the rear box if you don't need it)

ABS, oil cooler and 325i struts and dampers would be options.
Gearbox, prop and diff can stay,
poolnoodle
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Fri Oct 16, 2009 1:30 am

Thanks Mark, just piecing things together at this stage.
The is very solid and on good nick with new struts and springs so would be looking at minimum engine / ECU / loom at this stage.
What about radiator and other ancillaries - how much can be retained?
'83 Bronzit 323i (mmmm, chrome)
'74 Polaris 2002 (mmmm, retro)
'89 Delphin 535i (mmmm, waft waft)
bobcat
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Location: mid north coast australia

Fri Oct 16, 2009 8:33 am

poolnoodle just upgraded from M10 1800 to M20 2300 power is a sh#tload better but still don"t have the option of chipping,plus would also extract as much out of the M20as possible within reason.maybe the 325 efi/ecu might be worth considering,the 2.7 stroker would be the ultimate for me but the fund situation comes into play.
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