Z06 air intake question

[hand_coder]

Is the front opening on the C6 Z06, there is what looks like an air intake, see photo.<br><br>I've been told that Z06 engine air does not really enter there, it is just a styling "feature"?

True?

 

[Hib Halverson]

Yep. A styling geegaw.

I've been wondering how to make it functional.

 

[Iroc2Vette]

I just looked at mine. I thought it was functional. Nope. It's blocked off. That's the one thing I don't like. Reminds me of the plastic hood louvers on my previous car. A styling measure that just collects a lot of dirt and makes take longer to clean the car. If there's no function for it, keep it off the car, imo.

 

[Hib Halverson]

I got instructions on how to make it functional from Jim Hall at Halltech.

Haven't done the work, yet. When I do, I'll post about it.

 

[hand_coder]

I got instructions on how to make it functional from Jim Hall at Halltech.

Haven't done the work, yet. When I do, I'll post about it.

Interesting, would like to see how that plays out.

 

[Iroc2Vette]

I dunno...I'm seeing some issues to doing this in me 'ead:

1. Does the air flow going over that area of the hood create a vacuum at the position of the decorative duct? If so, it might actually hurt performance by fighting the air flow going into the filter intake assembly. Usually, the bottom of the windshield is the best place to gain positive pressure because air tends to pile up there. If there is a laminar flow over the hood, there could be some sort of negative pressure vortex happening there underneath the air flow. Therefore, no 'ram air' effect, but, suck vacuum might be more like it.

2. Opening up that area might also cause problems when it rains heavily, or a vehicle splashes water up onto the nose when going through ponded water. The water might go into the intake and into the engine, possibly causing a hydro-lock situation?

3. One would also have to be very careful not to blast hose water onto the front of the hood during cleaning for the same reason as item #2.

Perhaps it's better left as is?

 

[hand_coder]

I dunno...I'm seeing some issues to doing this in me 'ead:

1. Does the air flow going over that area of the hood create a vacuum at the position of the decorative duct? If so, it might actually hurt performance by fighting the air flow going into the filter intake assembly. Usually, the bottom of the windshield is the best place to gain positive pressure because air tends to pile up there. If there is a laminar flow over the hood, there could be some sort of negative pressure vortex happening there underneath the air flow. Therefore, no 'ram air' effect, but, suck vacuum might be more like it.

2. Opening up that area might also cause problems when it rains heavily, or a vehicle splashes water up onto the nose when going through ponded water. The water might go into the intake and into the engine, possibly causing a hydro-lock situation?

3. One would also have to be very careful not to blast hose water onto the front of the hood during cleaning for the same reason as item #2.

Perhaps it's better left as is?

All valid points. What can I say, an inquiring mind wants to know? But please don't ruin your engine.

 

[Tuna]

I got instructions on how to make it functional from Jim Hall at Halltech.

Haven't done the work, yet. When I do, I'll post about it.

Does the Halltech modification take into account rain and car wash water and keep the water off the air filter?

My previous "fresh air" cars had water diversion channels to keep the water out of the filter and the engine. Oil impregnated air filters are good at repelling the water however.

One fresh air system I installed on a GN many years ago was mounted below the bumper and the vertical hose to the air filter kept rain and wash water from getting to the filter and engine. Had to worry about driving in deep water though - can't have the air scoop become a water scoop.

 

[Iroc2Vette]

That's something similar to what I did with my old car. I used HVAC metal ducts, etc., to fabricate twin intake snorkels to go under the front valance panel, just in front of the air dam panel for the radiator. The twin 4" dia openings were elbowed on to 4" dia. vertical circular ducts, each feeding into a 6" x 9" (or something like that) rectangular stack duct just under each filter panel. The top clamshell of the air intake system fitted over the dual filter panels as normal.

I was able to get a lot of ram effect at highway speeds w/o worrying about water getting into the engine due to the upright position of the duct work.

 

[Iroc2Vette]

I have to revise what I said earlier in the thread about my front opening. I just shined a flashlight into it and was able to see triangular shaped lights reflecting on the air intake. It appears it is open. And the way the air intake is shaped, any water that does come in will go around the intake air cleaner and down and out of the car. So it is, indeed, functional. At first I thought it was blocked off. But, now I can see how it's set up. I guess it slightly pressurizes the air around the air cleaner at highway speeds. But, doesn't let in so much as to allow water to overwhelm the shedding ability of the moulded air cleaner.

I also found a warning in the owner manual that directly spraying water into that opening could cause water to get into the engine. So care is needed when spraying water on the nose during cleaning.

 

[JOV]

I have to revise what I said earlier in the thread about my front opening. I just shined a flashlight into it and was able to see triangular shaped lights reflecting on the air intake. It appears it is open. And the way the air intake is shaped, any water that does come in will go around the intake air cleaner and down and out of the car. So it is, indeed, functional. At first I thought it was blocked off. But, now I can see how it's set up. I guess it slightly pressurizes the air around the air cleaner at highway speeds. But, doesn't let in so much as to allow water to overwhelm the shedding ability of the moulded air cleaner.

I also found a warning in the owner manual that directly spraying water into that opening could cause water to get into the engine. So care is needed when spraying water on the nose during cleaning.

I also did the same thing a couple years ago with a flashlight and peaked under the front of the car and yes I can see some light entering from the front opening. So if you can see some light then some air is getting to
the air cleaner. It may be just a little but it at least is getting some !!

 

[Hib Halverson]

That's something similar to what I did with my old car. I used HVAC metal ducts, etc., to fabricate twin intake snorkels to go under the front valance panel, just in front of the air dam panel for the radiator. The twin 4" dia openings were elbowed on to 4" dia. vertical circular ducts, each feeding into a 6" x 9" (or something like that) rectangular stack duct just under each filter panel. The top clamshell of the air intake system fitted over the dual filter panels as normal.

I was able to get a lot of ram effect at highway speeds w/o worrying about water getting into the engine due to the upright position of the duct work.

I'm surprised you were able to observe a lot of ram effect at just highway speed.

How did you measure the ram effect?

 

[Iroc2Vette]

I'm surprised you were able to observe a lot of ram effect at just highway speed.

How did you measure the ram effect?

Though I couldn't do any direct measurement of increase in acceleration, I did feel a sizable increase in throttle response at speeds over 60 mph. I also noticed it was taking less time for the tach to reach red line than before. This after I removed the ECM fuse for 30 seconds, then drove around for about 15 minutes to allow the ECM to re-calibrate itself. After that, I'd go out on the the highway. The Merit Parkway here has very short entry ramps. Which allowed me to do WOT runs to 100 mph or more, depending on traffic conditions. It did seem I was hitting the higher speeds in a short period of time. But, again, I only had my butt-o-meter to tell me what was going on.

The other thing I think that also needs explanation is the intake below the panel filters was incredibly restrictive. There was actually a incased box (very shallow) with only tiny intake vents on the sides to allow air in. My guess it was to reduce the hydrocarbons from unburned gas from escaping into the atmosphere. I'll try to dig up a picture of all the parts I had to remove to free up the air flow. It was amazing the engine could even breath.

Here are pictures of the prototype system I made and the pieces that had to be removed. Note the vent pieces on the right. They formed a tight shell with only tiny vents on the side to allow air into the engine.