M20b23 l-jet to motronic 1.3

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gazwhittle
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Mon Jan 13, 2014 7:05 pm

Hi guys just after a few things clearing up really. I have read a few threads and guides ect and I'm getting confused with information.

I know I require;



ECU
Crank Position Sensor & Brack
Toothed crank wheel
Engine bay loom Inc Injector Loom
Cylinder Identification sensor
Oil Level Sender
Distributor cap and rotor arm
Temperature Gauge Sender
Camshaft dust cover
Camshaft rotor adapter
Injectors
Air Flow Meter

The question is I currently have a later b23 engine in my car and a complete 1988 b20 (which I'm sure is motronic 1.3) can all of the above be transferred onto my b23?

Also including the inlet manifold and throttle body or will I need a b25 inlet and throttle body?

Also will the injectors work or will I also need b25 injectors

And last question is the ecu fine or do I require a b25 ecu?


Thanks guys
Grrrmachine
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Mon Jan 13, 2014 7:37 pm

The b20 will provide most of the parts you need, but you're right in thinking that you'll need the b25 manifold and throttle; the b20 ones will work, but they'll restrict your engine. Your parts list is also missing the idle control valve and associated rubber pipes.

The key is your ECU. There is no motronic ECU for a b23, so you'll have to have your car properly mapped; using a b25 will make the car run rich, which will negate any benefits you gain from going to motronic 1.3. Your choice of injectors will depend on this.
gazwhittle
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Mon Jan 13, 2014 10:36 pm

Mmm would it be possible to use a b25 ecu with a reprogrammed EPROM ? Is this something that is readily available?


I don't want to spend much money on the doing the conversions or it would be easier to drop a b25 in.
jimbom30cab
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Mon Jan 13, 2014 10:48 pm

sell all the 323 and 320 stuff and put in a decent 2.5 engine

probably pay for it's self which would be







Free

Don't get much cheaper than that.
gazwhittle
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Mon Jan 13, 2014 10:53 pm

Yeh it's looking that way. It was an idea why I had the complete 2 litre motor sat in the garage doing nothing.
jimbom30cab
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Mon Jan 13, 2014 10:54 pm

if the 2.0l engine is motronic 1.3 then you will be able to sell that as a conversion kit (except the ECU)

the con rods are popular with engine builders also
gazwhittle
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Mon Jan 13, 2014 10:57 pm

What sort of price would the complete engine sell for.
jimbom30cab
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Mon Jan 13, 2014 10:58 pm

b20 - maybe £100 ? maybe £150 if in good cond with history
e30topless
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Mon Jan 13, 2014 11:02 pm

Gaz I have a good B2.5 here I can let you have for £200
Speedtouch
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Mon Jan 13, 2014 11:05 pm

See mattyb's thread to get an idea of what's involved:

http://www.e30zone.net/modules.php?name ... 78&start=0
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
gazwhittle
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Mon Jan 13, 2014 11:05 pm

With all acc ?
e30topless
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Mon Jan 13, 2014 11:09 pm

gazwhittle wrote:With all acc ?
Most of them, you will have what isn't there on your b2.3
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Brianmoooore
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Mon Jan 13, 2014 11:11 pm

gazwhittle wrote:What sort of price would the complete engine sell for.
Whatever the current value of a M20 flywheel and M20 sump is.
jimbom30cab
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Mon Jan 13, 2014 11:14 pm

dizzy cap + rotor
HT leads
cam cover
sensors




got to be worth more than that Brian
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Brianmoooore
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Tue Jan 14, 2014 12:05 am

Distributor cap and rotor are service items - if they're virtually new they might be worth something, but it'll be a pennyless loser that swaps one clapped out set for another slightly less clapped out set!
HT leads are useful to someone who finds themselves with a car with after market rubbish fitted, but supply must outstrip demand for these, so of limited value.
Cam cover? I suppose someone might want it to 'do up' while keeping their car usable.
I might remove the crank sensor from a B20 before it goes to the metal yard, if it comes out without a fight, but the plastic cable sheath tends to be brittle on most.
It's a bit like scrapping a complete car. Someone might pay good money for the bracket that holds the ECU or the plastic end panel that closes off the glovebox if you keep them long enough.
pacerpete
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Tue Jan 14, 2014 9:10 am

It's all about the glovebox plastics ! :D
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