Like many components for our FI systems, AARs are NLA. If you find a working one you're on borrowed time with it.

This is also one of the few pieces that is NOT replaced if you replace the factory FI system with a modern PEFI system (Microsquirt, Megasquirt, SDS, and so on).

I have designed a replacement kit based on a modern solenoid valve and a stainless-bodied thermal switch. The thermal switch gets mounted in the factory location for the thermostat, and the valve gets mounted on top of the engine in a protected location. The system is separately fused and is rated for 20k switching cycles.

Of course, this is not for CWs but it is a 100% bolt-on modification that could be reversed if desired. I would expect installation time to be 1 hour or less, including jacking up the car if needed to remove the existing thermostat.

No pics yet as I'm still designing / fabricating but is there any interest in me putting a kit together and supplying it?

I'm in, like to see some pics though.

AAR = Auxilliary Air Regulator that lets additional air into the plenum ?

Yep, this thing...pictured on a 1.7L plenum. This is the DJet AAR, I think the LJet ones look a little different but do the same thing.

Click to view attachment

Pics will take me a few weeks to get together but I will definitely post them when the install is at or near complete.

Do you have a ball park price? This wouldn't be a 500.00 dollar kit?

ha!

I'm guessing cost will be around $100...that would include the fuse and holder, wiring and connectors, fittings, brackets, valve, thermostat, fasteners, instructions. I'm expecting you can reuse your existing vacuum hose.

Great idea ! The one thing I would like to see in an upgraded AAR is an adjustment screw to control the limit of the aperature.

This solenoid you talk of, is it a fast acting open/shut style valve? Or, is it a linear acting servo that recieves voltages from the thermistor?

What will happen to the thermostat? Tossed, replaced or modified ?

Jim, do would you want to adjust the low (closed) limit or high (open) limit? I could add a feature/option to control the high limit pretty easily.

For those blessed with a functioning a thermostat, it would remain in the stock location. Minor modification of the bracket may be required but I think I can keep it as-is.



It's a fast-acting on/off solenoid valve. The proportional and damped / slow-acting devices I found are cost-prohibitive (the device would exceed the total cost of the kit).

I have a great deal of interest in in this kit for my L-jet. Would love to bring my AAR set up to a more modern era. Keep us posted.

The AAR is neither related nor connected to the thermostat.

Hey Rich, Glad to see your working on something for initial cold idle speed.

A solenoid would be perfect for stock FI as it doesn't get power from the ecu but from the ignition harness. It would be the thermostat that is tricky but if you could do and adjustable thermostat switch then even better.

The high end.

I mentioned mounting a thermal switch that triggers the solenoid in the stock thermostat location.

I will try to find a suitable location on top of the engine to mount this switch. That way the whole thing could be done without getting under the car.

Yeah, I'm with Andy. Are you talking about the thermostat bellows on the bottom of the engine? What's that got to do with the AAR?

While you are in the design mode: an updated thermostic-bellows would be nice too...

The stock AAR uses heat from 12 volt current and closes within 10 minutes. I think his idea is to trigger the solenoid using engine temp from the thermostat area .

Correct!

I have some ideas to replace the thermostat too one project at a time.

falconfp2001,
While the AAR doesn't get power from the ECU, the ECU provides a ground signal to allow the fuel pump relay to close, which does power the AAR and fuel pump.
Sounds like a good idea and I hope Rich can come up with a workable replacement. Now we need an inexpensive replacement for the trigger points.
Tom

I certainly hope Rich comes up with an alternative to an important but NLA part for one of the many control devices used by the D-jet or L-jet system, however, If you have an AAR that still heats up when connected to 12 volt souce, you already have one of the easiest to restore parts of the entire D-Jet system, why re-invent the wheel? This part, after being exposed to 35+ years of various degrees of "clean air" becomes dirty and simply won't close properly, even though the heated bi-metalic spring tells it to..........A simple cleaning will restore most of them to new like condition. The first requirement though is to have one that heats up when connected to 12 Volts. The L-jet AAR has a means of adjusttng the starting aperature size, thereby allowing manipulation of the closing as well. Any one interested in further details can feel free to contact me. I want to say, also, that I ment, in no way, to hijack this thread. I would still be very interested in seeing what Rich has to offer......Jerry

I'm interested