The instructions for my boost elbow state to put it on the turbo, and thats where its liveing at the moment but friends say doing that will slow the AFC down and cause slow fueling, causeing even worse performance than not haveing the elbow at all- any truth to this?

 

No.

 

When you change the fuel plate, the elbow controls boost pressure. Without it, you can overboost resulting in generating super heated air resulting in higher EGTs. If you have a stock turbo and a set screw on the new boost elbow, set the boost pressure at WOT to 34-36psi. That's pretty much at the top end of the effiecency of a stock turbo. You have a boost and EGT gauge, right???

 

False. The elbow allows the wastegate to open at a higher pressure. Without it, it will wastegate at the factory setting unless you truly have enough fuel to overboost with the gate wide open. In which case, the elbow wouldn't change that.

 

I think you're both right

 

so its ok sitting on the turbos output feed line and wont cause AFC lag? I dont have guages, figured the stock turbo and stock injectors cannot get me in to much trouble. And I dont leave it WOT for any length of time

 

I used to peg a 30psi gauge around 1/2 throttle on stock timing, injectors, and turbo with wastegate pinched....

 

If you're running a 10 plate, then you should have gauges. I'd bet you'd be surprised how fast the EGTs climb along with how much boost you're making even with stock injectors. As for Tate's response, you're correct assuming the additional fuel doesn't raise the output of energy from the exhaust above the factory wastegate boost setting. However, I think the posters set up will take him above that point. My first set up used a 30 psi gauge and only a (from memory) a 5 plate which was not that strong but I was able to peg the gauge without an adjustable elbow.

 

Riddle me this. If the wastegate would not be able to control the boost when it opens at 20 psi, how would it control it if it doesn't open until 30 psi?

 

Ok. I'm wrong. The factory elbow will only open the wastegate at the max factory setting regardless of fuel level. Lets try this, too little boost = high egt when adding fuel. Set screw allows more boost for more fuel. Without the adjustable elbow, EGTs are through the roof. He still need gauges... Better?

 

The AFC gets its signal from the intake manifold which is down stream of the intercooler from the outlet of the turbo. I had my elbow mounted on my AFC with the stock HX35 as I was trying to maintain a 35-38 psi in the intake manifold. But thinking now with a typical 1-2 psi drop across the IC, I was over working the turbo as the pressure outlet on the turbo was probably out of its range.

Either way, the AFC "Lag" is totally up to the signal it gets and the adjustments you make to the spring tension and zero boost settings. You may get more lag with the setup I had as the bleed off on the elbow at the AFC may cause the pressure to lag, but that orifice is in thousandths of an inch.

Now the turbo I have is all internally set with the WG signal at the outlet horn of the turbo.

 

Ok perfect, Good to know that it gets its info (pressure) from another point somewhere, Im looking into some nice piller guages now- since I do plan to tow in the future, what guages do most perfer? I plan to adjust the spring tension and zero boost settings in the summer, as I have HUGE AFC lag- so much so that when i let my friend drive the truck he swore it was takeing off in 2nd gear