Swapping a 2.0 for a 2.5 help please??

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SIA263
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Wed Mar 16, 2016 4:07 pm

Hi am a swapping a 2.0 auto for a 2.5 switchable auto.
Is it a straight swap of engine and boxe. If not then please can you let me know what else needs changing. 2.5 has the sport setting. new to all of this so any help is appreciated.
Regards Ahmed
Topblag
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Location: Fife - You got a problem with that ?

Wed Mar 16, 2016 6:08 pm

Switchable auto has an ECU in the boot, behind the trim the jack sits on. Also prop shaft is a different length and I assume the main ECU will need changed also. You'll need the handbrake console with the switch for the interior and you may need some extra loom sections to tie it all together. I think the interior selector may also be different as I think all switchable have a cable selector instead of a lever.

You'll need a different diff ratio to do it properly.
1990 325i Cab auto in Alpine White II
1988 Alpina C2.5 moredoor in Black, 71k
1990 325ix, moredoor auto in Laser Blue. 51k
1984 Hartge H35 in Black
2004 996 C4S in Silver 43k manual
2006 Audi S6 V10 in Black 58k
Topblag
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Location: Fife - You got a problem with that ?

Wed Mar 16, 2016 6:40 pm

If it's not a cabby or touring, you'll need front struts, dampers, ARBs, springs, possibly rear disc conversion - there's probably more....
1990 325i Cab auto in Alpine White II
1988 Alpina C2.5 moredoor in Black, 71k
1990 325ix, moredoor auto in Laser Blue. 51k
1984 Hartge H35 in Black
2004 996 C4S in Silver 43k manual
2006 Audi S6 V10 in Black 58k
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dave525
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Thu Mar 31, 2016 1:32 pm

Use the 2.0 box. Then you don't have to swap wiring,props etc. mine does 70mph at 3200 ish rpm.
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cory58
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Tue May 31, 2016 4:41 am

Topblag wrote:If it's not a cabby or touring, you'll need front struts, dampers, ARBs, springs, possibly rear disc conversion - there's probably more....
Why would those front suspension parts not work with an M20b25?
1992 325i Cabrio
1988 320i Touring
2015 328i
2001 325i (R.I.P.)
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