What is the purpose of using a new fitting with a smaller hole on the AFC when installing an upgraded cam or torque plate? Wouldn't this make it "think" there is less boost at first? What if I just kept the original fitting on?
I have a #8 plate

 

The boost elbow "tricks" your turbo wastegate into opening at a higher pressure resulting in more boost.
I rarely use an elbow, prefer to block off the line to the wastegate totally instead.

 

I am not talking about the boost elbow mod to the wastegate. This is pretty much the same piece only it goes in the AFC housing. It doesn't/can't control the wastegate.

 

I'm not sure what you are talking about, do you have a link or pic? What does the fitting you are talking about do if it doesn't control the wastegate?

 

It depends on which year 12 valve you have. On pre '96 the wastegate elbow goes on the back of the AFC, after '96 it goes on the turbo.
I know of no fitting that goes inside the AFC.

 

Go here for pics
drolex.net
drolex dot net

Go there and you'll see what I'm talking about.

I might have figured this out. We all know that the torque plates come with a new brass fitting of some sort, right? Is that fitting supposed to controll boost levels? I didn't get my kit from TST. I bought it on eBay and the fitting they gave me was just like a stright through 1/8" to 1/4" barbed connector. Everyone's directions, such as TST's, that I've seen for installing the plates kinda suck at some parts. Before I installed the plate there was just a boost line coming out of the intake manifold going into the back of the AFC housing. That is how I have it set up now, only I use the new fitting, but for what purposed I did this I do not know. Just following directions. I know the TST kit comes with a different fitting than what I got. Maybe you're supposed to have it going to the AFC and connected to the wastegate somehow? Do I even need this though if all it does is controll the boost? I already made variable boost controller that works very well.

 

You don't say what year your truck is but if there isn't a line going up over the engine from the AFC to the turbo the elbow goes on the hose in between the wastegate and turbo. Or you can just cut the hose and hose clamp a bolt inside the hose on the side that goes to the turbo.

If you install the "elbow" in the line from the intake to the AFC it will mess up your fueling.

 

My truck year is stated at the top of the page with pictures and there is a picture at the bottom of the sticker on my truck with its info. It's a 1996 auto. Why would the line from the intake to the AFC mess up my fueling? That's how it was stock. From what you're saying, I gather that all the "elbow" does is controll the boost. I've already said that I have a boost controller and I was trying to confirm that I don't need a different "elbow".

 

Infidel what kind of boost would a guy see if you block that hose?

 

It would just alow your turbo to max out, so, it would depend a little on your turbo and your mods. With the HX35 I'm guessing that you might see 35-38 psi with no wastegate.

 

The line that goes from the the manifold to the back of the housing feeds pressure to the AFC diaphragm which controls fueling according to to boost. On the older trucks this line was teed into and ran to the wastegate. The boost elbow on these was installed in the portion of the line going to the wastegate with the line to the AFC left free flowing. Newer trucks use the pressure from the output of the turbo to control the wastegate, the hose is only about 12" long instead of going over the engine.

The amount of boost with a blocked wastegate varies according to fueling but should stay under 36 psi unless you are really pumping the fuel to it, i.e. #100 plate, 375 injectors and a heavy foot.

 

That's how I thought it was supposed to work. So, how I have it, if the AFC sees less boost than there actually is at first, due to the new "elbow", I'm guessing it will supply less fuel than possible at first (until the pressure builds up). I don't think it would really mess up the fueling much. I think it's possible that it may help MPG slightly. I mashed the pedal quite a bit on this tank of fuel, yet also drove conservatively, and now I'm going on 550 miles and the fuel light hasn't come on. There's supposed to be 10 gallons left when the fuel light comes on. I don't know how accurate that is, but if there's 10 gal left at 550 mi then I've used 25 gal and that's 22 MPG with mashing of the pedal. This is also my first tank with the #8 plate, and yes, it made a big difference with my setup.

 

I have a boost controller (not even blocked hose) and my boost goes to 40+ psi. I have a stock turbo (12cm housing).