C25xe automatic to manual conversion

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Ahmed hassan92
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Joined: Wed Dec 20, 2017 5:22 pm

C25xe automatic to manual conversion

Post by Ahmed hassan92 »

Hello everyone

I got a 94 v6 c25xe automatic and want to convert it to manual transmission...where i live it's rare to find v6 parts, only 2.0 & 1.6 liter engines...can i go with the f20 or f18 gearbox with their flywheel and clutch and cable and pedals???

And what about the mounts and the shafts and the inner and outer joints???

Thanks in advance
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Robsey
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Location: East Manchester

Re: C25xe automatic to manual conversion

Post by Robsey »

Regarding the gearbox, I would look at the f20 as a minimum or f28 (6 speed box).

You will need significant wiring changes to the injector loom, and may perhaps need a manual specification ecu.

Interior wise you are looking at a complete clutch pedal assembly and cable.
Then there is the manual gear lever, centre console trim and gearbox linkage assembly.

No doubt both left hand mounts will be different. And on many engines, the exhaust front / down pipe may be attached differently.

The drive shafts should probably still fit fine.

I know EnvoyCDX converted his C18NZ auto to 18SE manual, so he would have been able to advise how he did it.
Sadly, he rarely visits the forum now, due to his own restoration being on ice.
cavalier1990
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Location: Paisley, Scotland

Re: C25xe automatic to manual conversion

Post by cavalier1990 »

I've changed my c18nz to manual however going from the 4 pot changes, which are quite straightforward to a 2.5 is, I would imagine, a whole other kettle of fish.

As robsey said there is likely a lot of wiring changes to be done a whole loom for a manual would be best, or even from an Omega 2.5 Manual (wiring loom) may fit right on. You may need to reprogram with tech 2 to tell it that you are using manual gbox.

The clutch pedal aperture should be there, all you need to do is take out big brake pedal, put smaller one in, and put the clutch pedal in. that's assuming the c25 is the same way in the pedal box.

Sorry can't be more specific however if you view how it is done on an omega this may give you some clues, only difference I would imagine is the actual gearbox and positioning of things, and driveshaft/mount stuff being different and I think the v6 has a hydraulic clutch, which you would need to plumb in.

Found this on omegaownersforum, think it covers all variants:

http://www.omegaowners.com/forum/index. ... ic=90592.0

Hope that helps.

Andrew
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