Megasquirt Support Forum (MSEXTRA)

Looking for suggestions here....Its a 2 litre Silvertop Zetec running Triumph throttle bodies each of which has a 6mm bore tap-off point on the engine side of the butterfly. On the bike these fed a small common plenum that provided idle air via a stepper motor controlled valve. I know ITBs don't provide much help with MAP readings so I may end up with alpha-N or hybrid alpha-N. However, I still need to sort some form of idle control. Simplest for me would be a 2 wire Ford idle control solenoid on a simple plate that feeds idle air to all 4 ITBs. I'm wondering if this will compromise any useful MAP I may be getting.
Advice and suggestions welcome......
Thanks
Gareth

Map will likely be high at low rpm regardless. Each port to a common plenum (I use fuel rail stock) to a 2 wire valve is the easiest imo.

Hi Paul, Went ahead and built up a copper plumbing bitsa on the back of a Ford ICV. We are getting 80KPa at Idle, just need to sort out the control for the valve now. The angled inlet pipe will have a small 'K&N' type air filter to feed clean air in. Still work in progress (as they always are!) but cooland goes in today and we can run it more then.
Cheers

Gareth

As my ITBs don't have any form of throttle stop I'm wondering if its feasible to let the idle control solenoid control idle speed at all times, not just during warm-up. I'm fairly sure Ford runs it all the time.

radiogareth wrote:As my ITBs don't have any form of throttle stop I'm wondering if its feasible to let the idle control solenoid control idle speed at all times, not just during warm-up. I'm fairly sure Ford runs it all the time.

This is how my ITB-equipped car works.

OK, anything special needed in the idle setups? I'd be grateful for pointers.....
Thanks
Gareth

On mine used alpha-n,

Set the idle with throttle stop that I made and the map.
Never used an idle valve ever. Daily drove the car through out the year all weather never had a problem.

Nothing special needed for me. I run closed loop idle with pretty standard settings.

radiogareth wrote:As my ITBs don't have any form of throttle stop I'm wondering if its feasible to let the idle control solenoid control idle speed at all times, not just during warm-up. I'm fairly sure Ford runs it all the time.

Doing a bit of research for a potential customer contemplating CBR600 ITBs, I noticed the '01-06 models used a coolant pod for warm-up air only with an adjustable throttle stop. The '07 design dropped the coolant plumbing and throttle stop in favour of a stepper IACV.

Yes, the Triumph ITBs had a small stepper-based idle control system that fitted to the original airbox, hence no throttle stop as part of the system. It was expandable to 4 ports but not easy to feed with clean air in this situation. Plus the inherited wiring loom came with it set-up for a 1-wire solenoid and I had one in the spares box. Choosing 'Closed loop' is the bit I was missing. If the engine tries to stall I see the Idle% shoot up but its normally at 0%. What I was sort of hoping for was a 'target idle rpm' box where that idle RPM can be chosen, with added warm-up on top, as per most cars. Back to the manual and software for a play later today I hope.
Thanks for inputs...

Gareth

Some progress this end, engine is now capable of cold start and warm-up plus some basic no-load tuning with a WBO2.

As far as I can tell the Ford ICS does not fully close when not energised so I guess I set everything up for a reasonable idle when warm and NO control signal (or very small) going to it. When cold its going to need a bit of extra air and at that point the ICS should get a signal. Or it would if I hadn't sent my TIP122 to semiconductor heaven

Electronically I can't see any reason why I cant replace it with a suitable FET like a IRF510 which was designed for switching duties. Or even a Logic level FET (rated at 30 amps, not that it needs 30 amps!)

Comments from successful users of 2 wire Ford ICS very welcome....

Thanks

Gareth