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#1 Steve_Wright

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Posted 21 December 2010 - 02:26 PM

Okay, first off this was all done on a 1990 1.6 auto (slightly different for the manual, see later) using a 94-95 1.8 motor.

The bits you need are:
1.8 engine, complete with inlet manifold with injectors & throttle body
1.8 engine mounts
1.8 exhaust manifold
1.8 cross over pipe
1.8 ICV plug


Posted Image


everything else you use off your 1.6.

first off, swap the engine, work that out yourself, its easy, I didn't remove the gearbox to do this. While you have the engine out, swap the waterpump and cam belt on the 1.8 engine, much easier to do with the engine out.

Posted Image

A few things to remember:
Make sure you swap over the 1.6 oil pressure sender
Block off the EGR stuff, I made some ally plates to do this on the inlet manifold,
Posted Image

and had a blacksmith weld the one on the manifold and install a bung for the O2 sensor at the same time
Posted Image

Auto and manual exhaust manifolds are the same, it is the front pipe that is different.

You can modify the 1.8 coil pack bracket to mount the 1.6 coils inside, requires some cutting with a grinder and some new mounting holes for the coils. Once bolted up I also glued the coil pack in with silicon, belt and braces, really not needed.
You will need to extend you CAS and temp sender wiring on the back of the head by around 6in
I had a spare CAS plug with loom I grafted into the 1.6 loom to extend it
Posted Image

This was before I taped them all up, plug on the top right here.
Posted Image

Alternator wise I kept the 1.8 one, just fitted a bigger eye to the loom on the car, or you can fit the 1.8 pulley to the 1.6 alternator, either way works fine (only upto 98 alternators, later alternators are different).

On my install I used the 1.8 intake pipe & thermostat housing. I have grounded the the fan control wire that connects to the 1.6 thermo switch to earth, this means the fan runs all the time the engine is running, not ideal but this swap is about doing on the cheap. I will sort out a second hand kenlowe fan switch in the future. The 1.8 crossover pipe will connect up to the 1.6 air flow sensor, the air box is a tad small so you need a decent hose clip to get it tight.

On the auto you get a variable TPS like on the 1.8, all you need to do is get a second hand loom side plug and swap it with the 1.6 plug, then set the resistance as per the haynes manual.
On a manual you will have to swap the TPS switch from the 1.6 TB to the 1.8 one.
Same goes for the ICV, the plugs are different so you need to replace the 1.6 plug with the 1.8 one

1.8 ICV
Posted Image


And thats basically it :thumb-up: , the stock 1.6 ecu with run the 1.8 motor fine with the standard 1.8 tan injectors. Like i said the only compromise is the fan running all the time, which can be sorted by a fan controller off ebay.

cheers
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#2 Vindi (Russell)

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Posted 21 December 2010 - 03:29 PM

Cheers for the write up & the pics, I will have a good read of this before I get started... this is exactly what I needed!! :goodjob:

Russell.
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#3 Steve_Wright

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Posted 21 December 2010 - 03:49 PM

link to a fan controller switch on ebay http://cgi.ebay.co.u...=item41552747bf
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#4 Steve_Wright

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Posted 21 December 2010 - 03:50 PM

or a nicer, bling one http://cgi.ebay.co.u...=item230c6b03dc
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#5 BeardedMidget

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Posted 21 December 2010 - 04:52 PM

Top stuff! I always assumed it would be more complicated than that! :thumb-up:
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#6 Steve_Wright

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Posted 21 December 2010 - 05:03 PM

Just to add to the above you can swap over the thermostat housing from the 1.6 and use the 1.6 crossover pipe, will mean you can run the fans with the stock thermo switch
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#7 Steve_Wright

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Posted 21 December 2010 - 05:06 PM

The biggest headache on this swap was working out how to use the coil pack mounts from the 1.8, lots of umms & arhhs until I thought fook it and got the grinder out. I will get a better shot of the mount next time I am playing with the car, but basically you enlarge the holes where the 1.8 coils fit and chop the lip off at the top of the bracket to get the 1.6 coils to fit in
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#8 Steve_Wright

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Posted 22 December 2010 - 06:35 PM

oh, & forgot to add you need a 1.8 throttle cable, still have to fit mine, you can bodge the 1.6 cable but it ain't right :whistle:
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#9 Vindi (Russell)

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Posted 22 December 2010 - 10:04 PM

Cool, keep the gems coming... mine will have to go in soon!

Here's a question for you - do you have to use the 1.8 manifold? I thought the bolt pattern was the same, so any reason why you can't use the one off the 1.6 with a bit of welding to connect it to the CAT? Reason I ask is I have a Fujitsubo one on my 1.6 and its really nice!!

Russell.
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#10 Steve_Wright

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Posted 22 December 2010 - 10:35 PM

nope, the exhaust manifold is different, you need the 1.8 one
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#11 Steve_Wright

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Posted 24 December 2010 - 02:41 PM

Just disconnected the ICV, it idles at 1400 with it connected, 900 without. May be down to my TPS settings, will have to double check them and make sure I am getting the right values. The car has not been so good starting, even stock engine/ecu, could indicate running a touch rich, just brimmed it with fuel so will see how long the tank lasts. Performance wise it runs great, pulls like a train to 7k rpm :thumb-up:
It has put my supercharger plans back a bit now, did have plans to get the charger done before the first track day for me at the end of january, but with it running so well I think I will have some fun with it as is before playing with it again. :driving:
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#12 Steve_Wright

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Posted 04 January 2011 - 10:12 PM

Okay, its running rich, will get some photos of the plugs with 1.8 injectors, but I have gone from 33ish mpg down to 21mpg :doh: someone else on here who did the swap saw similar results and went back to the 1.6 injectors, which I will do when I can find them in the shed :rolleyes:
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#13 dogsbe

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Posted 04 January 2011 - 10:46 PM

Okay, its running rich, will get some photos of the plugs with 1.8 injectors, but I have gone from 33ish mpg down to 21mpg :doh: someone else on here who did the swap saw similar results and went back to the 1.6 injectors, which I will do when I can find them in the shed :rolleyes:


I would be concerned about plug in 1.6l injectors with an 1.6 ecu into a 1.8l engine. I dont know if that is standard practice, but I see a risk of running the engine lean. I would probably opt for a fuel pressure regulator and a wide band to set it up.
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#14 Steve_Wright

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Posted 04 January 2011 - 11:33 PM

will stick the O2 sensor in the exhaust and see how it is running, haven't had chance to play on it yet
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#15 Steve_Wright

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Posted 05 January 2011 - 05:13 PM

Have been playing with the TPS position today, away from the haynes manual setting (which is about 11 o'clock in a range from 10 to 2 IYSWIM) at 10 the engine runs on & has v little engine braking, at 2 the engine stutters at 2000rpm with the throttle ar less than 1/2. Going to stick the TPS at 12 o'clock as see how it behaves, wondering if the poor fuel economy is due to the ecu not cutting fuel to the injectors when coming off the throttle.
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#16 dogsbe

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Posted 05 January 2011 - 09:10 PM

I think it is a lamdba problem. Until it is fitted, I would not consider other options.

Oh by the way, I received a 1.8l engine today for my own conversion. I am a bit of a competition and need to keep to a 400 budget, but with having the engine rebuilt. I will easily make it unless I have to rebore the engine, then I will be a few quid over.
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#17 Steve_Wright

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Posted 05 January 2011 - 10:52 PM

I think it is a lamdba problem. Until it is fitted, I would not consider other options.


:confused: The O2 is fitted
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cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu


#18 samuli

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Posted 06 January 2011 - 01:24 PM

Before you SC it, read this and this, then change -99 head with intake cam mod on to it.
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#19 PaulusUK

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Posted 06 January 2011 - 05:32 PM

Wait you're running the 1.8 using the 1.6 ecu?

Obv the map will be different. That's why youve got crap mpg, but that's obvious right?

Using 1.6 injectors and running lean is not a good idea IMO. I'd definately be scared of the red line.

Theo whole point is to gain power right? It's kinda undone by sub optimal management.

I guess swapping the loom is a nightmare. I'd live with the mpg or get an aftermarket ecu.
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#20 Steve_Wright

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Posted 06 January 2011 - 06:36 PM

Dear me this is going off tangent, this is meant to be a "how to" ;) This is a known swap, yes it isn't perfect, but it is reliable and well tested, in a round about fashion I have done it for about £230.

Anyway, adjusted the TPS and run a tank through, now getting 29.5mpg :woohoo: better than 21! I doubt the MPG issue would happen with the manual TPS as it is just a switch

Oh & I fitted the 1.8 throttle cable yesterday too, no more bodged 1.6 cable :thumb-up:
  • 0

cheers

Steve

IMAGE_126-1-1.jpg

'97 Eunos Roadster B2 Limited 1.8 Auto B-2's thread

'96 Eunos Roadster special 1.8 Auto Red-2's build thread
'91 Eunos Roadster 1.8 Auto Red-1's build thread
'93 Eunos Roadster V-spec 1.6 manual, bone stock
How to fit a 1.8 in a 1.6 with standard ecu





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