Splitfire or KMS engine management.

Im going DTA s 80 pro for the standalone because its been well proven so far with the 20 valve motor

I play with loads of aftermarket ECU’s in fact I have probably tried them all (except at few)
Ok let me explain. Let’s assume you get the latest KMS ECU which is the MD35.

It has 6 ignition drivers but only 2 fuel drivers one of which is shared with A.L.S (but I’ll get to this later). This means it can run sequential spark but only semi sequential fuel. (two fuel drivers to run five cylinders this is already so wrong)

The first problem you will encounter is the crank sensor. KMS only allows 0-180° as the reference tooth. The Fiat crank sensor is 270° BTDC. So you either have to mount a custom toothed wheel and sensor or shift the firing order around until a cylinder becomes within the 0-180° window. You do this by 360 / 5 = 72° per cylinder.

Cylinder 1 = 270° BTDC
Cylinder 2 = 198° BTDC (270-72)
Cylinder 3 = 126° BTDC (198-72)
Cylinder 4 = 54° BTDC (126-72)
Cylinder 5 = 342° BTDC (270+72)

So we can use Cylinder number 3 or 4 as our new reference tooth. The Fiat firing order is 1,2,4,5,3 if we use cyl3 as our reference tooth the new order will become 3,1,2,4,5 if we use cyl 4 as our reference tooth then it becomes 4,5,3,1,2. (The mechanical timing of the engine doesn’t change this is ignition timing only)

So the ECU now thinks that cylinder number 3 or 4 is really cylinder number 1. You must be fully aware of this when changing any other settings and mapping the engine. (not a good start is it)

So now the spark is working (well we tricked it) what about the fuel.

Well to run fully sequential fuel we need 5 fuel drivers and a cam sensor. We only have two fuel drivers and the cam sensor which is out of phase because we moved our ignition timing. The Fiat cam sensors pick up at 78° BTDC of cyl1 but cyl1 is really now cyl3 or 4 so we now have to move our reference tooth for the cam sensor but hold on KMS only allows -180°-180°. Cylinder number 3 or 4 must be in this window or you will never achieve 720 sync. (to be honest I won’t go into detail here because we will never get 720 sync with only 2 injector drivers anyway) So now that you know you can only run batch injection how will you control 1000cc injectors with this method. (The ECU will never idle or fuel nicely)

Next A.L.S Well you won’t have that feature since it shares with injector 2 which we will need to use to drive the fuel. (but you didn’t want it any ways)

Idle, yet another problem as we use a Bosch PWM 3 wire so we need two idle control wires the KMS has one. The solution change to a two wire idle control valve like Ford or use scattered spark to idle. (not ideal especially with 1000cc injectors)

Next is your AUX functions. Great it has three of these but hold on two of them we have to use for very basic features.
AUX 1 will be used for cooling Fan
AUX 2 will be used for the VVC (it only has two conditions but we need three, TPS, RPM & coolant temp) o well guess we will be using only two of these.
AUX 3 will be used to control the water injection I would have put three conditions her (inlet temp, RPM and boost) but we can only use two.

You have run out of AUX's should you need more (the turbo boost control might be used as a fourth AUX but still)

Dare I begin to explain how poor the software is?

The bottom line is this ECU is far too basic for your setup in fact it struggles to control the standard engine let alone yours which needs a better level of control. Seriously scrap the KMS get a refund or sell it on if you have already purchased it’s going to give you nothing but headache.

Look at any of these:
OMEX710, Haltech Sport 2000, Gems EM36, AEM, Megasquirt MS3, Syvecs S6GP, Link G4 Xtreme.

If you need any further advice regarding aftermarket ECU’s just drop me a PM.