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 Post subject: 944 2.5 conversion to 3 litre back to 2.5
PostPosted: Sun Feb 26, 2017 6:31 pm 
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Hi,

My neighbour has recently acquired a late (1988) 944. Which has had a 3.0 installed due to a previous engine disaster. The 3.0 litre has now also expired with a broken cam belt. I am told the original conversion included the trany and most probably the DME???

The plan is to donate a strong 2.5 engine, trany and 2.5 DME to return the car to its original 2.5 state.

Questions:

Would the DME at the time of the 3 litre conversion have to have been changed due to the different engine management requirements?

If so would this have entailed chopping any of the DME wiring or is it plug and play?

Would there have been any mods to the engine wiring in the engine bay?

Is the throttle cable going to have to be changed back for the 2.5?

I'm sure there are more questions I'll post as I go. Anyone who knows about how this has been done please chip in with any useful info and words of encouragement!

I look forward to hearing from you :0)

Regards

Steve


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 Post subject: Re: 944 2.5 conversion to 3 litre back to 2.5
PostPosted: Sun Feb 26, 2017 8:43 pm 
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The DME from an 8v 2.5 wouldn't work with a 3.0. My 2.5 16v had a 3.0 DME and drove fine so unless the previous engine was the 2.5 16v you'd need to get an 8v DME

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 Post subject: Re: 944 2.5 conversion to 3 litre back to 2.5
PostPosted: Sun Feb 26, 2017 8:53 pm 
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wouldn't it be easier to just repair the 3.0 head? unless your going to add a turbo, wouldn't the 3.0l be a better option for power and torque?? i'm biased tho

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 Post subject: Re: 944 2.5 conversion to 3 litre back to 2.5
PostPosted: Mon Feb 27, 2017 1:14 pm 
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Definitely easier to stay 3 litre. The DME is different, the fuel pressure is different, 3.8 bar I think for the 3 litre vs 2.5 bar for the 2.5. There are many differences TBH. If it was me I would look to repair or replace the 3 litre lump. You're also surrendering 60 odd horses going back to 2.5L 8v.

Stuart

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 Post subject: Re: 944 2.5 conversion to 3 litre back to 2.5
PostPosted: Mon Feb 27, 2017 6:01 pm 
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I have a running 2.5lux as a donor, so I have all of the parts I need. But I'm starting to think the head rebuild the easier option coz of all the engine management variables! :roll: :roll:


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 Post subject: Re: 944 2.5 conversion to 3 litre back to 2.5
PostPosted: Wed Mar 01, 2017 12:39 am 
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9apart have a couple of heads in atmo.

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 Post subject: Re: 944 2.5 conversion to 3 litre back to 2.5
PostPosted: Thu Mar 02, 2017 10:04 pm 
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Comedy prices though, and Simon's children are arrogant beyond belief. The days when you paid a strong price but received decent kit and Simon nipped it 'round are long since passed.

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 Post subject: Re: 944 2.5 conversion to 3 litre back to 2.5
PostPosted: Fri Mar 03, 2017 7:42 am 
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944 Man wrote:
Comedy prices though, and Simon's children are arrogant beyond belief. The days when you paid a strong price but received decent kit and Simon nipped it 'round are long since passed.


Couldn't agree more with this. I've learned this 1st hand. Douglas valley I've found to be very helpful.

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