I’ve run k20 & ITBs with both MoTeC and EFI.
If you go with clockwise roller ITBs they have a very neat solution that builds on roller ITBs being far better (read more gradual) on first open and small openings in the first place. You can get very “drivable” results with just TPS on clockwise roller ITBs.
If you are on butterflys then you need to do alpha-n mapping if you want better drivabity. In effect you blend MAP for idle/small openings and TPS for the rest.
You might need to add a decent vac reservoir to get a stable MAP signal though as plumbing the MAP sensor direct into the body is going to produce very rough results as would using a vac res that is to small.
Hi Johnboy
the point is that you get most out of the engine with Hondata because you can benefit from VTEC plus VTC. Most of the other ECUs can only control VTEC or VTC.
We are happy with setup, but i regret to buy lazy-quality Jenvey ITB�s with custom MAP-mounting and custom stepper-motor-mounting.
Jenvey is far away from Japanese (TODA, CUSCO) or Austrian (PANKL-rods) quality standards.
With the new regs for LOTUSCUPEUROPE ITBs are not really necessary, because its easy to meet the 255-260 bhp at the flywheel. For this power a simple single throttlebody for 20% of investment would be ok too.
Driveabilty in everyday traffic is poor due to extrem lightweight flywheel and instant response of engine. With single throttlebody you pobably can map and drive the engine much smoother.
Anyway we are happy with the enormous torque from 2600 to 7000 rpm, and in addition the low powered engine is extremely durable and has practically now need of service.
BTW Ian from clockwise motion is a very competent Honda specialist. We built in his famous baffled sump and lightweight alternator set. But we are still waiting for his drysump solution.