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Discussion Starter #1 (Edited)
as i play with nissans aswell as alfas ive had the idea of fitting the ecu / sensors and loom from a nissan ca18 onto my twinspark engine.

the reason for this is i want a programmable efi system for a low cost. and can have a NIStune ecu installed or the nissan ecu re-mapped and the loom re-arranged to suit the alfa engine very easly and cheaply.

there is 2 big issues to making the nissan ecu/loom work with the TS:

first would be the need for 4 more coil packs:
im wondering... is it possible to wire a extra coil pack into the nissan loom (in series or parrallel??) for each coil, making the loom have 8 coil packs? and the ecu thinking it is firing just one but infact its firing 2 for each cylinder? i think this could work, aslong as the coil packs fire at the same time and there is no voltage drop between them, i cant see why not?

next would would be mounting the exhaust driven CAS, but as the TS uses an exhaust driven distributor it can be done, the dizzy can be removed, a shaft/adapter/seal made to go between the alfa camshaft, alfa head and nissan CAS, then a mounting plate made up and the nissan CAS mounted.

i think these are the 2 biggest issues, the others would be mounting all the nissan sensors on and in the alfa engine, but that shouldnt posse a problem and can i know it can be done, afm can be mounted easly, a custom plenum will be made allowing the use of the nissan fuel injectors and throttle body, tps and iac and the temp sensor can be made to fit the TS wherether it be by tapping existing hole or making adapter.

does anyone have any suggestions or advice as to how it can be made to work? or reasons why it can? its still all ideas and would be a good project. anyhelp / comments welcome :)
cheers, Brad
 

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BradGTV,
this is an intense project and probably not worth the time nor labour cost if you where paying someone to do it. This would involve heavy modifications that need to be dead accurate to make it work.
My advice is save your pennys and buy an aftermarket ECU which is fully probably. At least you can use this ECU for several applications if you wanted.
 

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I'm doing (for about 18 months now :eek:) similar, VL Commodore (RB30E) 6 engine management into a V6 75.

Things to consider are the accuracy of any machined parts that locate the crank angle sensor and the direction of rotation of the crank angle sensor. The V6 Alfa distributor turns the opposite way to the RB30 distributor. A dummied test showed that it would still fire the injectors, but the old RB30 ecu isn't sequential (batch fire) and the CAS sync cylinder slots aren't of different lengths like they are in the multi coil engines. If the CAS is mounted in front of the exhaust cam, sweet! But make sure its accurately mounted otherwise you will kill bearings.

As for driving 8 coils, use 2, 4 channel ignitors. It's just not worth the dollars to find out that 1 or more channels eventually die. Nissan used 'dumb' ignitors, so either 2 factory ignitors or a pair of after market 1s will work fine.

Obviously the original air flow meter is required. Well, at least until you get it running and then do the work to go a larger AFM.
Find out if the TPS is a variable voltage 1 or a switch type. If it's a switch type (like the RB30 1 is), the AFM signal is used for the transient throttle enrichment ('accelerator pump'), so keeping the AFM a similar distance from the throttle body (for NA) or turbo, would be a good idea.
If it is variable voltage (I know the both the 128kb and 256kb versions of the RB20DET ecu are variable voltage), then using that sensor is an obvious must as the Alfa/Motronic system is just a closed throttle switch.

Obviously the use of the Nissan coolant temperature sensor is preferred.

You wouldn't really be able to adapt the factory knock sensor to the noisy Alfa engine (you could give it a go, but I think it would be waisted effort). What you could do tho, is use the knock fuel and ignition maps as a switchable second map, it's a matter of feeding the right voltage to the knock sensor wire to get the ECU to switch to the knock maps.

Biggest challenge will be getting the speed sensor input into the ECU. Modifying the shape of the factory Alfa electronic speedo sensor signal could/should work, but I'm a fitter and turner, so...... :p

I think it's a great idea (but I'm biased). Just do everything you can to ensure the integrity of the Nissan wiring loom for the CAS, EGO sensor and the AFM to make sure the signal shielding is factory intact.
You'll also need ignition on and cranking signals from the ignition switch.
 

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Discussion Starter #4
marco, thanks for the suggestion, if i payed people to do my projects for me i would be in huge dept and there would be no fun in it for me. i honestly believe i can do this converion for well under $200. thats excluding dyno tunning (a couple of cartons of beer to my mate) and a NIStune ecu (advertiesd new for $440) or second hand for about $200-$300.

duk, thanks for the input, very interesting converion your doing, is there any particular reason for choosing the RB30 engine managment? is it easly re-mappable? i have consided doing something similar with fitting the delco system from a ecotec to an alfa v6.

what model car or engine does the 4 channel ignitors come out on? sounds promosing, however i dont have a great idea of what a ignitor does :eek:, would you care to explain? :)

regarding kock sensor, is it possible i could not use it at all?

hmm the speed sensor has got me wondering, not sure on what to do there, any ideas?

i too think its a good idea, and i beleive it can work well if the time is taken to gather enough infomation, at this stage the only thing worrying me is the speed sensor issue...

thanks again for the input, and keep me updated on your conversion ;)
cheers, Brad
 

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duk, thanks for the input, very interesting converion your doing, is there any particular reason for choosing the RB30 engine managment? is it easly re-mappable? i have consided doing something similar with fitting the delco system from a ecotec to an alfa v6.
RB30 ECU are cheap 'cause of the millions of VL Commodores they made and the ECU is early Nissan stuff with Nistune support or you can do it the old fashion way with an emulator (Nistune can work with an emulator, but thats probably the type 2 ECU).
Delco stuff was though of too, but given the similarities of the RB30 to the 3 litre Alfa engine, there should be less tuning to do away from the factory mapping. They also appear to share TPS and coolant temp sensors. I got the wiring loom, ECU, distibutor and AFM for less than $150.

what model car or engine does the 4 channel ignitors come out on? sounds promosing, however i dont have a great idea of what a ignitor does :eek:, would you care to explain? :)
The ignitor/ignition module switches the ignition coils. They can only sink so much current before the internal transistors burn out, so if you are doubling the number of coils, you'll double the current flow through the ignitor. Maybe it will live, but the reality is that is will probably die at a very inconvenient time. Use 2 of them so they are working as per the factory installation.

regarding kock sensor, is it possible i could not use it at all?
The Alfa engines have a lot of valve train noise. This noise will be picked up by the knock sensor. Some of that noise will probably be just the right frequency to sound like engine knock. If/when that happens the ECU will revert to the knock maps/low octane maps (there's 1 for fuel and 1 for ignition).
Even the hydraulic cam follower equipped Nissan engines have the knock flags switched off at certain point (above 3200 RPM in for RB20DET).
It may also pull out more ignition timing but I can't say for sure.

hmm the speed sensor has got me wondering, not sure on what to do there, any ideas?
Not at this stage. Knowing the shape of the Alfa signal and the shape of the Nissan signal would be a start.
It's not the biggest issue and from what I've read it effects things like the off throttle fuel cut resume (when the ECU starts to inject fuel again). But it may have some weird effect some other way, too.
 

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Spend the money on a Megasquirt box, trim existing ECU harness off, plug into Megasquirt. Download one of many tunes that will get you close and dyno that.
Look, I'm all for being frugal, but Megasquirt kills it for frugal. It will drive any coils and any injectors, just tell it and it does it. No need to buy ANYTHING except the ECU. All sensor inputs can be calibrated to any sensor out there etc.
A project like the one you are proposing will, to borrow an expression from our American friends, nickel and dime you to death. meaning all those little parts will cost a lot.
Seriously, 18 months? You'd have megasquirt running in a month.
 

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Seriously, 18 months? You'd have megasquirt running in a month.
You know what they say about assumptions..........
I started ages ago (guessing 18 months ago, but it's probably less), I stopped before completion.
 

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I thought about doing the exact same with but with the sr20 gear off my sr20 as i have ( been waiting for 2months to arrive yet) the doungle that plugs in to the nissans DDL port so you can get every reading off the engine even in gauge fourm to the laptop and also tune it etc.
But then i just thought it will be much more better using Mircotech in the long run. Yes it does cost more (new) but cheaper 2nd hand .
 

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marco, thanks for the suggestion, if i payed people to do my projects for me i would be in huge dept and there would be no fun in it for me. i honestly believe i can do this converion for well under $200. thats excluding dyno tunning (a couple of cartons of beer to my mate) and a NIStune ecu (advertiesd new for $440) or second hand for about $200-$300
Brad, good on you that you are having a go, there is nothing wrong with that. If you can get car dyno for next to nothing than that is an advantage and now I know why you are going ahead this project.

if i payed people to do my projects for me i would be in huge dept and there would be no fun in it for me
I never pay people to do my work, mainly because there work won't be up to my standards as I am a very fussy person. I converted my alfa to EFI for this reason, as well as not to pay 4-5K bill for something that I can manage by myself.
 

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But then i just thought it will be much more better using Mircotech in the long run. Yes it does cost more (new) but cheaper 2nd hand .
Just remember if you buy second hand, that you'll either have to have the crank angle sensor from what ever engine it was used on or you'll have to send it back to Microguess for reconfiguring (they don't have user configurable crank angle sensor set ups). And that adds extra dollars.
 

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Discussion Starter #11
well....

i got a ca18 cam angle sensor and started lookin into how it could mount on the ts head, which would very easy to do.

however i was looking on ebay and a microtech lt-8 popped up, and for the price i payed i couldnt go wrong, was cheaper than a NIStune ecu and came with a wiring loom. so couldnt say no.

so the NIStune idea is out the window :D

duk or others who are electronically minded. i need some help.
i will make a few changes to the loom and how its set up. i will lock my alfetta bosch electronic dizzy and mount in place of the crank driven TS one (only using the sensor in it, not going to distribute spark) then the ecu modifies the signal from the dizzy and fires the coil packs. because i need 8 spark plug out puts, i will replace the single coilpacks and add dual tower coil packs. probably from a hyundai excel. however i have been reading on some toyota froums about the 3tgte engine which is also twinspark, they say that using a dual tower coilpack to fire 2 spark plugs on compression stroke will damage the coils ?? the reason being that the coil normally (wasted spark) fires 1 spark plug on compression and the other in exhaust gases (nothing) therefore less stress on the coil. does this sound right? or will the coils be ok firind 2 spark plugs at the same time on compression stroke ??

cheers, Brad
 

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You will have to get the Microtech reconfigured by Microtech to suit what ever crank angle sensor set up you use. If you have the Motronic 60-2 wheel on the crank pulley, you should be able to use that with a good Hall Effect pick up, there isn't any 'Home' sensor built into the Bosch distributor, only the 4 trigger points ('cylinder sync') on the shaft and 1 electronic pick up (Hall effect, inductive or what ever they used) speak to Microtech about that.
You will be charged for the reconfiguring.

What you say about the dual output coils having a short life when used on 8 plug 4 cylinder engines does make sense. The current draw from the cylinder on combustion is higher than the cylinder on exhaust (when set up as waste spark), so the coils would run hotter and die faster. Better to take that advice and set up 8 individual coils.
 

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Discussion Starter #13
hmm interesting, the guy i bought it off, had it running on a turbo fiat, he said the only ignition pick up was from his bosch dizzy (2 wire) which is what i currently have. and what the wiring loom is set up for.
 

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hmm interesting, the guy i bought it off, had it running on a turbo fiat, he said the only ignition pick up was from his bosch dizzy (2 wire) which is what i currently have. and what the wiring loom is set up for.
But he was running a distributor. If you want to have 8 coils, the computer needs to know where the engine is. This is either done by having a 'home' sensor or the likes of the Bosch 60-2 trigger set up where the computer is configured to realize that the missing teeth means 'start again'.
Without some sort of reference to tell the computer when to start it's 1-3-4-2 (it's actually just 1-2-3-4, but things are wired in the correct order) cycle, the computer won't know where the engine is when it's been stopped.
Computer controlled engines that have sequential fuel/ignition need to find it's reference point when cranking on the starter motor before the engine will start.
 

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Discussion Starter #15
ok i understand now,

when using a distributer can the ignition timming be controled by the computer? looking through many of my pictures alot of TS turbos and nord turbo's are still using both distributers, even the 500hp one in melbourne does.. and i assume that would have to have a very well controled igntion system. or do with a dizzy can i only control fuel?
 

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Yes.
Distributors still work OK, but if you want or need some big zapping power, look at using a Capacitive Discharge Ignition system with the distributors (you'll need 1 for each coil, tho or a dual output 1). But that is the sort of thing for later when you start chasing those last few KW.
 

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Discussion Starter #17
thanks duk,
just wondering how the ecu would control the timing with a dizzy?
if its possible to use a dizzy, then i will use the bosch alfetta dizzy with its advance locked off, and mounted on the block, then use a nissan pintara rotor and cap to give me 8 spark plug outputs. however i will need an extra coil pack (will use the original TS ones for now) do the coil packs need to commincate with the ecu or can these just be set up to get power when the ignition is turned on??
cheers,
Brad
 

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the idea with the two dizzys integrated should work as i think thats how mine works.
 

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Discussion Starter #20
thanks for the suggestion, but i dont see how that will benefit me at all??

how urs work? i didnt know you had a ts running?

i plan to use an afletta dizzy, weld the advance mechanisms, then modify it to fit the nissn rotor and cap. simple and it will work.
 
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