Idea on Auto Adjusting Grill Block
 

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.
http://i47.tinypic.com/2mo13k9.jpg

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

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.

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.:thumbup:

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

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.

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,

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.

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)
http://i48.tinypic.com/zkg2on.jpg

Side View
http://i45.tinypic.com/2jahg7r.jpg

Closed (air flowing)
http://i45.tinypic.com/2mnq32f.jpg

:thumbup:
If it turns out in practice the weights don't work as well as you would like you could also design that counter force with a spring... If the weights work good enough in practice , it might be easier to fabricate.

For the basic flat plate version of the screen attached bellow are some quick crude pic I slapped together... Red and Blue indicate the different holes from the different screens... to Go from open to closed the front screen only has to move the size of the hole ... it can be designed to move vertically or horizontally.

For the 3D shaped version ... just think of a basic fixed angle blind ... mini size between the holes ... as the wind speed increased the force on that 3D surface increases the force on that front plate to move toward a favored design position ... which could be side to side or up down ... if side to side a spring or something might be needed to reset it when the high speed wind force is gone ... if it is up and down, the weight of the screen can pull it down as long as the slides are smooth enough.

The holes don't have to be circles , a variety of shapes could be used ... and the 3D surface doesn't have to be a flat fixed blind style a variety of 3D surfaces could be used.

Does this help picture it any?

As before ... the blind style can work fine... I'm not trying to convince you of any one method.

Oh, ok that makes much more sense. Thanks for the pictures. I am really liking how well this little model works when I blow on or or take a fan to it. If I blow softly, it only partially closes and a strong wind will close it completely. Just what I am trying to accomplish and regardless of how strong the wind is, it always returns to its original opened state without fail. Now I just need to find some coroplast and I can get the real thing going. When I finish it, I will strap my webcam to my bumper to create a video and adjust the weight so that it will completely close at as close to 45mph as I can manage.

P.S. fixed the duplicate photo to the correct one...

A lot of vehicles use a passive self adjusting system. As the pressure and velocity builds the holes in the grill create a blockage from interference drag. At highway speeds they only allow a fraction of the air through that they do with low speed.

Not sure if it is the best but think of a ford truck or car with a grill made from large wide flat plates with slots between them. The slots only allow much air at low speed.

well,I had a big cardboard box and some metal coat hangers that weren't getting any use, so I turned them into the rear weighed shutters I have been messing with. Slapped them on my car and they look and work pretty good so far. My temps stay where they should and after attaching a webcam to my car I was able to see that the shutters are opening and closing properly. The only problem that I am having is that they shutters are closing at about 25mpg, while I would rather them close around 40-45mph, but the cardboard setup cannot support the added weight :(

I really need to find some coroplast. I've got the itch to get this thing working, but am too cheap to go buy the stuff.

Here are some pics of how the shutters look on the car. I personally think they look pretty stylish. When I make the switch to coroplast, I will do a better job on the fitment to eliminate the gaps I currently have and I will also spray paint them black.

P.S. uploaded from phone so no license plate blocking here :o (you saw NOTHING!!)

http://i47.tinypic.com/28bd2e8.jpg
http://i50.tinypic.com/otp1y1.jpg

This is cool! I like the idea. Do you have a film published somewhere from the testing with a webcam. I'd love to see how it behaves when the speed increases.

Check with yer local sign shops fer some scraps... ;)

Thanks :)

I don't have the video anymore. I deleted it due to poor quality. My webcam isn't great and I needed to get some software on my laptop to get it to stop autofocussing every time the shutters move or I hit a slight bump. It was very laggy and at some points completely froze. I will re-attach the webcam soon and see if disabling autofocus helps. As I stated before, the cardboard can't take any additional weight. So it closes way earlier than I would like, so don't expect too much from the video.

For me the problem is more complicated because Berta is diesel and fitted with IC. So I need to have an opening for IC for all the time, maybe it would help a bit for faster warm up with closed air duct for IC during winter, but I don't think that gain will be measureable. Anyway I want to have one opening for IC and radiator with ability to restrict air flow through radiator. See the pic. Any ideas how I could manage that with the auto shutter setup?

http://ecomodder.com/forum/attachmen...1&d=1362645643

If I am understanding you correctly... This is the super simple solution I have come up with. Just do the exact same thing that I have going on, but cut out a hole where your IC is and put some ducting between the hole and your IC. This way you will have constant flow to your IC and everything else will open and close depending on your driving speed. I have made up a few pics to demonstrate what I'm talking about.

Hope this helps.

http://i46.tinypic.com/6fqccg.png

http://andrzejm.superhost.pl/Berta/front.jpg

That's the front view of Berta. As you can see I want to keep just the middle part of lower grille opened. So I was thinking more of some kind of blinds restricting flow through radiator (orange)
http://andrzejm.superhost.pl/Berta/auto_shutter1.jpg

I saw your car and for an instant saw a "Pontiac", I am very sorry.

Nice car. I like it.

I like the simplicity of the actuation based on airspeed. Using physical properties vs. electronics seems most reliable. This doesn't however address the issue of the stated need for additional cooling in hotter seasons or for increased cooling system requirements.

Short of the wax pellet actuator (like in the 70's water cooled VW airboxes) is there a better way to do this?

Ohhh, I see... Not sure what I was thinking earlier. Why would the IC be a tube, lol? Ok well how about doing something like this instead? Seems a bit easier IMO. I just modified my original idea for you (which was dumb) and cut a whole in the middle section, just not all the way through. As a plus, this would actually look pretty cool.

This still may not be what you're looking for, but hey I'm trying here :)
http://i49.tinypic.com/2s9oh01.png

Appreciate the simple solution, but some needs extra cooling in summer heat & very slow jams. ('shopped)

http://bunkerville.files.wordpress.c...raffic-jam.jpg

While cruising below whatever speed you weight yours for (mine will be 45mph) the blinds will be partially opened, or if going slow enough they will be completely opened. That means the only time you won't be getting air to your radiator (through the grill), will be at highway speeds. At those speeds the air will find plenty of other ways into your car, to keep your engine cool. During summer and traffic there will still be enough cooling. That was my reason for making it this way. I hit plenty of traffic in my area and here in north Texas it wouldn't be summer if it didn't hit 110F for at least a few days.

Thanks for ideas. I have to take out the bumper and check what I can do with space behind that. I'm thinking of sealing space around radiator to have a complete control over whole amount of air going through IC and Radiator. But first I have to move cooling fan behind radiator, because now it's at the front of it.
http://andrzejm.superhost.pl/Berta/cooling1.jpg

Yes, I think moving the fan to behind the radiator would make the installation a LOT easier. Also I agree (and was going to suggest) that sealing the space around radiator would help direct the air to where you want it.

Well, I found some left over coroplast, that I forgot I had, from my previous grill block that didn't go so great. Made a video of the grill block closing by mounting a webcam to my license plate. The video is not very good quality because I don't have a very good webcam, but it works well enough. It is a little better if you click on the gear near the bottom right of the video and increase the quality to 480p, after starting the video.

I was not able to record the slides re-opening because the camera kept lagging and freezing up. The slides do open back to where they started in the same way that they closed.

I am very satisfied with how this grill block turned out and I intend to paint it black and keep it on year-round. The only thing left to do other than painting is to add a bit of weight to the back side of the slides, so that it closes a little later. I will be aiming for the slides to close completely at 40 MPH

http://www.youtube.com/watch?v=ISXvY7ygK-o

Great work! From "idea" to "satisfied" in a mere three and a half weeks?!

That has to be some sort of record, right?

Cool! Great job!

Sarcasm? IMO it feels like I took a long time to figure this out and finally implement it. It turned out to be a very simple solution in the end.

No sarcasm at all. I'm still plotting everything. Instead of acting, I overthink. You thought it quick, worked it out, and implemented it. I'm genuinely impressed.

Well thank you very much :)

Still a few tweeks to do on it. Need to find a way to reinforce it a bit, it is starting to sag in the middle slightly. I also need to add a bit of weight to it so that it closes just a bit later.

I was kind of thinking maybe a very thin coat of fiberglass resin (no glass) might be enough to do both jobs at the same time by adding strength and a bit of weight. Anybody think that this would be a bad approach?

This is way cool! I wonder if I could rig up something similar with sheet aluminum for the gaping hole in the front of my Mustang?

~SM

Absolutely, it wasn't very hard to make actually. I will take a few more pics of the nearly finished project. I think aluminum might also have the same strength issues I am having, so you may want to find a way to make it more rigid as well. You can either cut away your grill (if it doesn't clip/screw on) like I did to install this, or you can simply install it behind your existing grill (a bit more drag that way I would assume) for a more stock look. If you decide to install it behind your factory grill, I would suggest removing your bumper to make installation easier. It would be pretty difficult to install behind your grill otherwise.

Mustang grilles are actually a bit recessed. I have an aftermarket aluminum one that's ever further back, and it deletes the GT fog lights, so I have a large, mostly flat expanse to work with. Did you already mention what you used to weight the flaps? A thin aluminum bar on the backside of the center area might be enough to stiffen it up, and could serve as the weight (depending on how much weight you need).

~SM

Actually right now mine is not weighted other than a few support bars I have running through the coroplast, which didnt do much good (that is what I get for making this thing for free). I used metal coat hangers that I bent straight and ran them through the coroplast from side to side. One on the top, one on the bottom and then one near the middle (a bit closer to the rear) which is used as the hinge point.

I will go outside now to get some pictures.

Ok, so here is the gist of it... I drew this up in Paint in about 5 minutes, so that I wouldn't have to take off the grill block and take it apart to show what is on the inside and how it all worked out. I'm not sure if anybody will understand this drawing, but I hope you get it. It also wouldn't hurt to add a verticle support (like on the sides) to the center. The fishing line is to keep the 2 pivot points (on the rear sides) from backing out of the coroplast without limiting their ability to rotate.

I have attached a few pics of the real thing as well.

http://i50.tinypic.com/1zeuhwl.png

To fix the sagging and some weight with the what you have I would trim a coat hanger and coat it in glue then push it through the coroplast. You could even bend the coroplast a little against the sag to help hold the shape.

One thing you should check is how the grill works with the fans running at full speed. You do not want to be stuck in 5mph traffic then have the fans turn on pulling the grill shut.

I like the idea and now need to think of some way to do that on the last 2.5ft x1in opening left at the bottom of my bumper.

That is a great idea! Why didn't I think of that?? I will work on that today. I have plenty of fiberglass resin, so I will just dip the rear hangers in that. I will put 2-3 coats on which should give enough stability to the hanger to keep it from bending. Thanks for the suggestion :)