Using a cars ECU and associated gubbins on a K Jet car

[pauloliver]

I'm just trying to get my head around this idea, so please don't shoot me down as I'm still trying to learn about it all.

If I were to get an ECU, wiring, sensors and whatever else I need from one car, could I 'simply' transfer it to another car of a different make but the same cylinder size? I have a Porsche 924 with a 2l NA engine and K jet injection which is in pretty much need of total replacement. This is more than i'm willing to pay for new and all the secondhand bits I acquire seem to be dead/on their way out. Is there any reason why I can't get an ECU setup from another car with a 2L engine and swap it all over? I know there will be the fabrication work to mount up the sensors, etc, but that aside would it actually work straight off once hooked up? If not then what exactly would prevent it from doing so?

Now I know the obvious answer would be to go with Megasquirt, and logical people do that but I'm tight fisted (I don't have that sort of money spare currently and i'm sure I can find a car to sabotage the parts I need off for not much money) and I enjoy a challenge to some degree. I seem to recall Saab made an ECU system that was supposedly easily home tuneable (Trionic 8?). Are there any Stock ECUs that are possible to DIY tune if I would need to? Also if I did this sort of conversion, would it be fairly simple for me to wire in a Megasquirt ECU later on down the line as all the sensors will be largely in place?

Cheers in advance for any help.

[Dez]

an ECU map is mostly down to cam profile, as its that what sets the characteristics of an engine more than anything else.

i think as a very minimum you'd need a new map to match your cam, but you may get lucky and get something thats 'close enough'.

if you plan to fit megasquirt later i don't see much point in doing it tbh. and if you do, make sure youre going to the trouble of fitting something that is megasquirt compatible, i.e. timed off 36-1 system.

[pauloliver]

Brilliant, that helps me understand more already, I didn't think of cam profiles! So if I found something with a very similar profile then it would be pretty much ready to go? Of course being that lucky is unlikely but i'm just talking theoretically here.

Maybe I'm just better off buying all the little bits and bobs needed for the Megasquirt install and getting things fabbed up as I go ready for when I can afford the Megasquirt ECU. the other option is to continue with my other idea of going 1.8T, and using the stock ECU system from that (with the immobiliser removed) as it wont be far off the cost of the Megasquirt system but will require more effort on my part

[BenzBoy]

What parts need replacing on your current engine? Is it fuel system parts? In my opinion it would make far more sense to get the K-Jet system running properly than try to get an ECU and associated fuel system from a different engine running on this car. I realise there is the Porsche-tax to deal with regarding parts prices, but do the parts needed not cross-reference to VAG stuff?
If you're going to go to all the trouble of wiring in an ECU it's best to make it worthwhile and save up for an aftermarket set-up. At least then you'll have a sweet-running engine with potentially more power at the end of all that work!

[baggabones]

To be honest I've never found much Porsche tax on 924 parts, even the specialist breakers are cheap enough and I've never struggled to get parts on the bay

[Ryannn]

When I had my 924 it was a real pain trying to get hold of K-Jet parts. Troubleshooting issues wouldn't always pinpoint the part at fault, just a group of them that needed changing. I almost boshed a pair of SUs onto mine!