MSefi.com read only forum (Jan.15,2018)

Ok Guys, I have built my Stim. and am up to Step 22 on building the mail board. (V3.0 MSII) Things are going well and I am pleased with the quality of the Board and surprised with the quality of my soldering.
I will build (fabricate) my own inlet manifold/Plenum for my 1971 Triumph Spitfire. (pic attached in relation to what I plan to do)



My question is where on this set up would a IAC stepper valve go? Your suggestions please.

Thanks
Rob

Is the throttle body the blue part? The stepper always has to bypass the throttle butterfly. This can be done with an integrated stepper, like in a GM Cavalier TB, or it can be done with a remotely mounted IAC and hoses.

I'd recommend going to a you-pull-it junk yard and looking at Cavalier and Saturn TB's if you want a stepper, or Ford Escort ones if you want a PWM IAC. These TB's all use IAC's that are integrated into the throttle body itself... so one less thing to worry about in your fab.

This is such a Saturn TB (left), and a separated Ford PWM IAC (right):



The black cylinder on the lower left of the TB is the IAC stepper.

Superb, I did not know that the IAC was intergrated to the TB.....

and yes the blue part is where the TB will sit.

I do not have breakers yard near me. I will have to make a trip and take a look at what is on offer, as you say an intergrated one will save loads of hastle.

PS.. I can see the TPS and IAC what is the other sensor? is it a temp sensor?

Thanks Rob

No, that other thing is just three vacuum ports fed into a molded plug.