why would u want to keep the stepper motor on a conversion

[hiltonig]

If the meagsquirt can support it what advantage is there in keeping the stepper motor rather changing to a 2 wire Iavc? I cannot see why other than the intial cost of buying the Iavc and plumbing it in ? any comments chaps ?

[adyw]

I found i got earth interferance with a bosch idle valve replacement over the original stepper motor, so I now run with no stepper at all. Once the engine is warm it's fine

[daxtojeiro]

hiltonig said:

If the meagsquirt can support it what advantage is there in keeping the stepper motor rather changing to a 2 wire Iavc? I cannot see why other than the intial cost of buying the Iavc and plumbing it in ? any comments chaps ?

Why would you want to get rid of it? I have a bosch idle valve on mine as thats what I used to develope MS1, before MS2 came out, and I havent bothered changing it back. As long as its built right with the flyback diode then you can use it without issues. But if you have the stepper then Id stick with it,
Phil

[paulathome]

Phil, why would you go with the stepper motor over a Bosch PWM idle valve? The stepper motor seems to give grief to many owners due to the muck blown back to the stepper motor housing causing poor seating of it'd tip. Look on most of the TVR forums and the first thing most poeple say is "clean your stepper motor". They do seem very prone to sticking and require regular maintainance and to be honest I disconnected mine and the car runs perfectly without it after a mile or so of driving.
Just a question to satisfy my curiosity as this spring I will hopefully be ordering one of your kits for my Chimeara as a summer project. I have read through most of your excellent web site gleaning as much info as possible and collecting the various bits of hardware over the last few months ready for the big swap over.

[spend]

Additionally you have to question the longer term continued supply of Lucas parts (particularly of acceptable quality). Replacing old (ie unsupported) components with more modern alternatives is quite a significant advantage in updating the ECU IMHO.

[Pupp]

That said, I suspect the 'resolution' of the Lucas stepper is superior to the 2 wire PWM type valves insofar as they seem to give a finer range of possible openings. At least, that's my experience but the 2 wire valve I have is a pattern one and may not be as good as a genuine Bosch component