Ok, this is for any memeber that has ties and info on OEM parts

I'm going to go efi on my 6 with PMO ITB's. I will be making a vacuum canister to tie all 6 ports together to get a good vacuum signal for the MAP. I want to also incorparate a IAC into the canister to control the Idle. The ECU uses an IAC 53030657AC (Chrysler) which crossed over to a Delphi CV10155.

What I'm looking for is technical specs to machine the mount for the IAC.

Can anyone help ?

Paul

You may have trouble with a IAC valve, it will let air leak past at idle and cause your map to read wrong also you will have a hard time syncing up your ITBs .

Syncing will be done with the vacuum ports blocked off so that shouldn't be a problem. The idle air control/map signal/ and fuel control are all handled by the ECU and software (Holley HP EFI) Currently I'm using a 4bbl Throttle body on my 914 V6. The IAC on the TB just bypasses air into the plenum under the throttle plates (same vacumm reference the MAP sees and uses) so it should be ok unless I'm missing something here.

I wanted to do itbs with SDS which also uses a map, but SDS talked me out of it. There is too much leakage past the butterflys, so idle is unstable. IAC is for hot vs cold idle, not erratic idle, right?

How does Clewwet do it, I wonder.

You mean this?
http://www.diyautotune.com/catalog/custom-...valve-p-69.html

And it won't fix a highly erratic idle, but it will fix the sometimes it's a thousand, sometimes it's 800 RPM idle.

Well, sort-of. This is from the Holley manual:

The IAC is located in the throttle body of the TBI and MPFI. The valve consists of a stepper motor that adjusts the position of its pintle to vary the bypass air during idle and off idle conditions. During the closed throttle condition (idle), the ECU constantly compares actual engine speed with the programmed desired engine speeds. Discrepancy between these two values result in activation of the stepper motor increasing or decreasing the bypass air around the throttle plates until desired engine speed is achieved. This operation is similar to a controlled vacuum leak

At idle, the throttle plates are always patially open so leakage doesn't really come into play. Erratic idle isn't the issue I'm trying to address.

I'll have to check clewwet's site to see what they do.

That's sort of what I want. I want to machine the end of the aluminum vacuum canister to fit the IAC I need to use. This block does't have the air inlets/outlets and the IA motor in the positions I need plus the IA motor isn't the one that works with the HP EFI system.

I don't anticipate a high erratic idle problem but I'm no where close to finding that out.

If I can't find or get any technical info, worst case I'll go out into my sub-zero garage and remove the TB from my V6 and try to measue the mount opening.

The IAC is a electronic throttle the CPU measures the engine temperature with a sensor and determines the the throttle must be open a little to let the gas/air mixture to be rich to start. This is fine on a engine where the engine has a plenum
and equal length runners to the heads. On a engine with ITBs this can cause a problem as the IAC runners must be the same length to each cylinder, but the real problem is that the IAC will flows too much air and will confuse the CPU. I had the same problem with my 914 engines and I went to a solenoid to operate the throttle body linkage just like the 911 with a throttle lever mounted on the floor.

This what I found when I try a IAC.

All it does is step a pintle in out out, just like an air bleed screw. Doesn't change mixture other than letting more/less air in. All they are is a small stepper motor, usually 3 wire ones are all the same, and 4 wire ones are all the same, just different dimensions. My GM throttle body has one built in, and my Jeep is a separate one. I can measure the GM one if you need it, but I need the Jeep right now.