What is that little vacuum into airbox on RENIX?

[HenryKrinkle]

Should be getting my Rusty's short ram air and an AEM DryFlow filter setup in a couple days. Running through it in my head, I remember a little vacuum connection that goes into the rear of the top of the airbox. What is that for? Can I just plug it off?

I know the ccv will connect into the Rusty's tube (I'll eventually do an inline oil catch can for that), but I don't think there are any other bungs on it for other hoses. In fact their website says you may have extra connections and to just plug them off.

I'd rather know what it is and how it could affect the Jeep.

Any help is greatly appreciated!

 

[Digger87xj]

you can cap it off.
It's for the hot air mixer. It uses vacuum to open the flapper valve to regulate hot air into the box.

 

[joe_peters]

you can cap it off.
It's for the hot air mixer. It uses vacuum to open the flapper valve to regulate hot air into the box.

Yep, thermactor air system, and you will also not be using the exhaust manifold stove either.

 

[Shorty]

Yep, thermactor air system, and you will also not be using the exhaust manifold stove either.

thermactor air injection is actually the smog pump equipped V6 air injection recirculation (A.I.R.) system.

the hot air stove and bypass valve (butterfly on inlet) are coupled to the bi-metal vacuum switch that re-directs vacuum to the butterfly when hot is called an air intake pre-heater system.

either way, you can plug and bypass the vacuum lines to the bi-metal switch. Once you replace the air box with the filter and tube, you will no longer have the ability to "pre-heat" the air anyway.

 

[joe_peters]

thermactor air injection is actually the smog pump equipped V6 air injection recirculation (A.I.R.) system.

the hot air stove and bypass valve (butterfly on inlet) are coupled to the bi-metal vacuum switch that re-directs vacuum to the butterfly when hot is called an air intake pre-heater system.

either way, you can plug and bypass the vacuum lines to the bi-metal switch. Once you replace the air box with the filter and tube, you will no longer have the ability to "pre-heat" the air anyway.

Your right! FSM terminology is TAC--Thermostatic Air Cleaner, consisting of the exhaust manifold stove, the bi-metal valve, and the vacuum motor.

And yes, you can plug the vacuum line without problems.

 

[Shorty]

Thermactor was (IIRC) a Ford Motor Company for the A.I.R. system they used-- Pulsed Air Injection is the AMC/Chrysler name-- I think I've got that logged away in the cob webs correctly.

 

[joe_peters]

Thermactor was (IIRC) a Ford Motor Company for the A.I.R. system they used-- Pulsed Air Injection is the AMC/Chrysler name-- I think I've got that logged away in the cob webs correctly.

Yes, trademarked name if I remember right (which obviously I don't)!

 

[HenryKrinkle]

Thanks a bunch fellas. I'm looking forward to a little extra power. The '88 is lacking a bit compared to these little modern cars.

Rusty's website claims an MPG increase too, but I sort of doubt that. How has yours been Joe?

 

[joe_peters]

A little more noise (normal), maybe a little more "seat-of-pants" response. Haven't tracked my mileage much since I changed to 31s and then re-geared. I put maybe 10 miles a day on it through the week and then 4x4 on weekends, so its pretty hard to tell.

The last real trip I took with it was about 200 miles, mixed highway/steep hills, this was after 31s plus Rusty's tube with K&N cone, but before re-geared, and it worked out to 18 MPG.