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Discussion Starter #1
Any of you guys that do a lot of dynoing ever paid attention to the positioning of the bung for either the 7th injector or the alcohol injection and how that affects the engine's reaction to the mixture being injected?

Let's take water/alcohol injection for example... Is there a significant difference between mounting the injection in such a way that it sprays the mixture OPPOSITE the airflow as opposed to spraying it angled to go WITH the airflow? If I am understanding this right, introducing the mixture against the airflow will allow for the 2 (incoming air and the mixture being injected) to mix better. So this then would allow the tuner to use a denser water/alcohol mix which in turn will have more effect on how the engine runs. However, is it possible that the benefits of running a higher density mixture negated because the introduction of the mixture going opposite the airflow slows the incoming air down enough to where it hurts performance?

My other concern is regarding the location of the injection. Have you noticed any significant difference between placing it in various locations either on the charge pipe or the manifold itself? I imagine the only place to avoid putting it is anywhere that the mixture might pool when the airflow is suddenly cutoff (such as letting off the throttle during a pull due to mechanical failure). Is there any impact on performance by moving the injection to various spots on the manifold or piping leading to the throttle body? Differences between pressure/flow right at the turbo as opposed to right at the throttle body are substantial so I imagine it would make a difference as to the placement. Also, is it not a good idea to have it inject inside the intake manifold itself because it is very difficult to have the mixture distribute at the same rate as the air does by itself once inside the manifold? I imagine placing the nozzle close to any one runner increases the chance that the one runner will get more mixture than the others or if the nozzle is placed right at the throttle body (on the plenum side of the manifold), the incoming air at the throttle plate will send the mixture to the opposite end of the manifold.

Any thoughts are welcomed.
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