Having done a load of research into a new ECU to manage all the functions I want available: -
CAN bus 2.0B (for PDUs, display, external data logging)
Analogue and Digital I/O (wheel speed sensors, fuel, water, oil, brake, cylinder head pressure and temperature inputs, turbo speed, fan, fuel pump control etc)
Thermocouple/thermistor inputs (EGT etc)
Lambda circuit for 5 wire lab grade sensor
Advanced knock control
Closed loop boost control
Closed loop fuel control
Traction Control
VVL control
Anti lag
Water Injector control
DBW strategy
Ethernet PC connection
Internally data logging
etc etc...
I've decided on a Syvecs S8 ECU.
So now as i'd previously bought all the accessories needed for my HKS Vpro, it's back to the drawings board for all the temp/pressure sensors, boost solenoid, lambda sensor, etc etc and more importantly a completely new wiring harness for all of this stuff. Nice thing about the HKS Vpro is that there's a S15 specific loom which I bought, so now I think it's custom loom time.
I've wanted to go the whole hog and have an Autosport connected loom, with Raychem 55wire and DR-25 tubing, the only thing putting me off was the cost of the tooling for the deutsch autosport connectors, you need a DMC crimp tool and a bunch of pin positioners , I think you won't get much change out of a grand in all and that's before the wire and connectors. So bit by bit this year I will purchase all the tooling for this.
Back to now and a few parts just arrived: -
Whiteline ARB link kit (rear) - front on order and new AEM Coils for the VVL head, need to run these with a CDI box and that will be the M&W Pro 14 unit. Max who's also doing a VVL build found that the P12(20V) rocker cover can use standard S15 coils, what a result and I would have gone that route if i'd know before purchasing these coils, but committed now and will have probably needed the extra juice from the CDI box anyway. But it would have been nice to have the P12 cover with a nice set of Okeda Projects coils, oh well...