Idea on Auto Adjusting Grill Block

[Shortie771]

So I tried a grill block on my Honda Del Sol and it was a definite no go. On the highway it was just fine, but when I got into the slower town areas or a high traffic area, I started to see my temps rise because the fan had become restricted to how much air it could pull in (which was weird because I had a pretty big hole in it). Well, in the summer it gets over 100F every year (gotta love Texas)... I don't want to have to constantly be worried about over-heating and monitoring my temps. I also dont want to put a grill block on and have to remove it every time it gets hot. I want a grill block that can stay on all year, so that I am always getting the benefits and not have to worry about over-heating in the summer.

So I started thinking of how to make a grill block that would adjust itself according to how fast I am going... I know I could make a fin-style one or a slide for the opening and attach a motor or cable to it, but I am going for something completely worry free that I dont have to take my hands off the wheel for.

What I have come up with (still not sure if it will work, still in the planning stage) is a fin-style grill block that has an additional fin (perpendicular) on both sides. When the car is still (or at low speed) the grill block portion will remain open, but when the vehicle gains speed air is pushed against the verticle fins which will cause them to tilt. When they tilt, they will push the levers upward causing the grill block portion to close. The levers are attached on the back portion of the grill block (larger) fins, so that they will naturally want to close, making it easier for the air to close them. With this design, I believe it would be possible to mount a camera to the fron of the car to see what speed allows the grill to close completely and then the (what I just now have decided to call) Activating Fins could be weighted to close at any desired speed.

This is just an idea at this point, but I would love some feedback. I hope I explained this ok without confusing anybody.

Here are some terrible pics I drew up in paint.

[Vekke]

cfg has done testing on that same idea in this topic:
http://ecomodder.com/forum/showthrea...lock-7603.html

[Shortie771]

Thats funny. I just found one of his videos on YouTube and was going to post it into here. I like the spring idea, but I think that this idea might have a bit cleaner look, since I can put it behind the grill if I want (probably won't though). Maybe a bit more adjustable as well. Then there is the whole thing about trying something original I'm thinking I will attempt this in a few weeks after I put my Coroplast belly pan on. I will duct the air that passes through the activating vents down and under the car. Though I might want to duct in to the radiator instead. Trial and error will be the judge of that I suppose.

[IamIan]

FYI ... another variation possibility.
Instead of the tilting blinds style is to have two screens of holes when the holes line up air passes when the holes don't line up grill block.
best of luck either way.

[Shortie771]

Originally Posted by IamIan

FYI ... another variation possibility.
Instead of the tilting blinds style is to have two screens of holes when the holes line up air passes when the holes don't line up grill block.
best of luck either way.

How does that work without any sort of motor, cable, or manually adjusting?

[radioranger]

He's onto something there but how about a grille block made of screen that doent restrict the flow at lower speed but as speeds increase less increase in flow and more will bypass screen because of resistance, In other better words only so much air will go through the screen no matter how fast you go , but is sized so that at idle you still get lots of air,

[Shortie771]

Originally Posted by radioranger

He's onto something there but how about a grille block made of screen that doent restrict the flow at lower speed but as speeds increase less increase in flow and more will bypass screen because of resistance, In other better words only so much air will go through the screen no matter how fast you go , but is sized so that at idle you still get lots of air,

Good idea but I wouldn't know where to start to make that work, nor do I have a way of testing to see how much air is flowing through the screen. Also I don't know how that would be adjustable for higher heat situations to allow more flow through... Say at 25mph the fabric stops pulling in additional air; Well that isn't going to change, but what if it is 100F+ outside and you need more air traveling through at speeds above 25mph. The only option at that point would be to remove it or cut holes in it.

Definitely a great idea for colder climates.

[radioranger]

I see your point , a quickly removable screen might not be too hard to rig, they use bug screens all over Florida and the south i know, I figure if your running hot you could slow down for a bit and the air would cool it off, of course not an option on the highway, perhaps a baseline run on an average day at your normal speeds with a temp gauge underhood, that could get you close to optimum, opening shutters of course would be cooler. another option maybe would be a adjustable spoiler tab to pull more air from the engine compartment down,

[IamIan]

Originally Posted by Shortie771

How does that work without any sort of motor, cable, or manually adjusting?

AFAIK both version ... be it blinds or the sliding screens both have to have an adjusting mechanism ... both need some type of mechanism... or they are fixed and don't adjust.

The Blind style sees the most pressure on it as the air speed increases ... It can be designed to either close from this increased air speed ... or open from this increased air speed ... which ever one way you design it , in order to make it do the other would require some type of over-ride mechanism that is strong enough to overcome the forces.

In the screen version you have some additional options:

#1> If you make the two screens flat , then the screen mechanism is nearly equally easy to open or close at slow or fast wind speeds ... unlike the blinds which would have a favored position one way or the other.

#2> If you design the screens to each have shaped holes in a more 3D style system, the front one 3D toward the front and the Rear one 3D toward the rear , they could still easily slide past each other , but one would design the 3D surface to create a wind flow preference ... so that like the blinds , it has a preference to be either closed or open at faster wind speeds , or slower wind speeds... I suspect the front most screen would have the most impact from the 3D shape, and the rear one might be able to be left as a flat screen without loosing much travel ability in the mechanism.

#3> You could also have a mechanism attached to the #1 above ... a solenoid , linear motor, etc ... depending on how elaborate you want to make it ... it could be a simple open / closed ... or you could give yourself various degrees or steps between 100% open and 100% closed ... this could be manually controlled by the driver ... or it could be setup as feedback from something else, sensor, etc.

One nice thing about screen system is that the screens do not have to move as much as a blind style would have to , to have a similar open to closed change.

Another nice thing about the screen is that one really only has to work out movement for one screen ... the front one maybe ... as the entire screen moves it effects all the holes lining up with the second screen ... a blind style , needs each of the blinds to be hinged, and each blind to have a moving mechanism... ie more points of potential failure.

Also the blind style needs more thickness clearance room than the screen version does... the blinds are X thick when closed , and have to have the clearance to turn to be open Y thick when open air flow... the screen are always equally thick open or closed.

The blind style system can end up working fine ... if you prefer it ... use whatever you like ... I was just pointing out a possible alternative option to consider.

[Shortie771]

Thanks for all of the info. I am still not understanding the screen style. I guess I just can't picture it for some reason. Grabbed wht I could find around the house... Fishing line, toothpicks, cardboard, super glue and some screw (used for weights). I made a mini prototype of a version of the blind style, but I changed it. Instead of having it be closed by opening the side vents, I have weighted the back portion of the blinds and installed a stopper so that they cannot go farther than about a 10 downward degree angle. So when the car gets up to speed, the wind will overcome the weight of the back portion of the blinds and force them closed.

Open (no air)


Side View


Closed (air flowing)