Nice work Bob.
I like the job you did Bob.. A bit cleaner than the fan shroud I made and probably more efficient..
I took a bit of heat on my design and I will be modifying it slightly to account for the potential of a positive pressure on the backside of the radiator core due to a potential restriction of airflow presented by the shroud. My plan is cut a couple of 2" holes through the shroud between the fans - one above and one below - then putting a rubber flap over the hole.
If the pressure behind the core is negative, then the fans are doing their jobs and pulling air through the core. If the pressure moves to the positive side, then hopefully the flaps will open.
Many made the point that it is very important to seal off the area around the grill to ensure that all the air coming through the grill opening "must" go through the radiator... This is also consistent with my experience.
Here is the thread I made roughly 5 years ago for reference..
http://www.gt40s.com/forum/gt40-tec...e-cooling/30519-gt40-radiator-fan-shroud.html
...
Since you have the ability and facilities to do some real world flow analysis, I am keenly interested in what your findings are...
...
Again, some very nice work you are doing there!
...
Another similar thread for reference (you may have already seen all of these)
http://www.gt40s.com/forum/gt40-tec...gine-cooling/37512-fitting-fans-radiator.html
I took a bit of heat on my design and I will be modifying it slightly to account for the potential of a positive pressure on the backside of the radiator core due to a potential restriction of airflow presented by the shroud. My plan is cut a couple of 2" holes through the shroud between the fans - one above and one below - then putting a rubber flap over the hole.
If the pressure behind the core is negative, then the fans are doing their jobs and pulling air through the core. If the pressure moves to the positive side, then hopefully the flaps will open.
Many made the point that it is very important to seal off the area around the grill to ensure that all the air coming through the grill opening "must" go through the radiator... This is also consistent with my experience.
Here is the thread I made roughly 5 years ago for reference..
http://www.gt40s.com/forum/gt40-tec...e-cooling/30519-gt40-radiator-fan-shroud.html
...
Since you have the ability and facilities to do some real world flow analysis, I am keenly interested in what your findings are...
...
Again, some very nice work you are doing there!
...
Another similar thread for reference (you may have already seen all of these)
http://www.gt40s.com/forum/gt40-tec...gine-cooling/37512-fitting-fans-radiator.html
Guys, thanks for the nice comments.
Randy,
I'm glad to see your post from 2010. I wish I had seen it sooner. You did a good job on fabrication and there was some good discussion.
I have quite a bit of room between my fans to put split delta shaped trap doors as suggested by several people and I plan to do so. They will have to open from vertical hinges since my nostril splitter is very close to the shroud.
I have already made some steps to seal the area in front of the radiator (see my post #130), but I think I will try to do some more. There were some good suggestions on your thread.
I actually have plans to do a lot of testing with my flow bench that will include air velocity plots, torque and speed measurements of the motor, along with various configurations of shroud/no shroud, condenser, etc.
-Bob Woods
Randy,
I'm glad to see your post from 2010. I wish I had seen it sooner. You did a good job on fabrication and there was some good discussion.
I have quite a bit of room between my fans to put split delta shaped trap doors as suggested by several people and I plan to do so. They will have to open from vertical hinges since my nostril splitter is very close to the shroud.
I have already made some steps to seal the area in front of the radiator (see my post #130), but I think I will try to do some more. There were some good suggestions on your thread.
I actually have plans to do a lot of testing with my flow bench that will include air velocity plots, torque and speed measurements of the motor, along with various configurations of shroud/no shroud, condenser, etc.
-Bob Woods
Darrin,
I used 0.063" and I'm pretty sure it is 6061. It bends just fine.
I welded the sides on since I didn't know a good way to get the complex bends for the radiator hoses if it were all one piece. A square indentation for the hoses might have worked so you wouldn't have to do as much welding.
I'm tempted to come over and help you since I've been through this and have the equipment.
-Bob Woods
I used 0.063" and I'm pretty sure it is 6061. It bends just fine.
I welded the sides on since I didn't know a good way to get the complex bends for the radiator hoses if it were all one piece. A square indentation for the hoses might have worked so you wouldn't have to do as much welding.
I'm tempted to come over and help you since I've been through this and have the equipment.
-Bob Woods
Your welcome to do so (especially the welding)!
Let me get things close then we'll work something out. They have a good restaurant or two around here and I'll get your lunch at least. Or I could just bring it out to you when it's to that point as I'll probably make it removable as you did.
I'll get a sheet of 29" (24 width plus 2.5 + 2.5 for each side offset) by 13.5" (10.5 + 2.5 + .5) in .063" 6061 then and start fabricating to get it close. My engine is SUPPOSED to be in next week so that might slow me down a bit.
Darrin,
You need to be cautious of the clearance to your nostril splitter. You can't make the shroud too deep if it will conflict with the splitter. That is why we need to do it at your house.
Maybe we can invite Sam and Gary and Pete over too. I'm eager to see their cars.
-Bob Woods
You need to be cautious of the clearance to your nostril splitter. You can't make the shroud too deep if it will conflict with the splitter. That is why we need to do it at your house.
Maybe we can invite Sam and Gary and Pete over too. I'm eager to see their cars.
-Bob Woods
Don't think everyone would fit! LOL
I hear you on the clearance. I'm thinking it might be at issue. I'm going out to measure in just a second.
My thought was to do all of the work measuring/prototyping in place then doing the final weld, but doing it here is more than fine by me. Let me get an update on the engine to see when it will make it in (be great to show that bad boy off....it's supposedly quite a beast) and we will convene here.
Oh, I meant you're nor your. Was answering via phone.
Darrin,
Your fab work looks great.
I've had to take a side step in my progress; but there is so much interest in the flow bench tests, that I will put it as the highest priority.
-Bob Woods
Your fab work looks great.
I've had to take a side step in my progress; but there is so much interest in the flow bench tests, that I will put it as the highest priority.
-Bob Woods
Camera Research
I now have three cameras and have made a preliminary evaluation that I wanted to pass on since there seems to be some interest in this and I suspect some of you are making decisions now. Perhaps this will give some insight into this subject, although I don't consider this the final solution.
The first camera is the one that came with the Tview RV808. It is advertised as a 1/3" CMOS camera with 628x582 pixels, 420 TV lines, 2.0 lux.
The second camera is the Boyo VTL 200.It was advertised as a CCD camera but when I got it, the box said that it was a 1/4" CMOS camera with 640x480 pixels, 380 TV lines, and 0.5 lux.
The third camera is the Boyo VTL 420.It is a 1/4" CCD with 512x480 pixels, 420 lines, 0.3 lux.
The first photo is all three cameras with the Tview at the top and the 420 at the bottom.
I was confused with the field of view, FOV.As I learned, the FOV is related to the size of the sensor and the focal length of the lens. I find FOV to be a misnomer because the so-called FOV does not really correlate with the "included angle of the video scene" which I will call the "included angle" (my word). I measured the included angle by measuring the width of the scene in the display and the distance back to that width and then used the inverse tangent of that half angle and then doubled it.
I have tested all three cameras for their clarity and included angle.
The second photo is the video scene on the Tview display from the Tview CMOS camera.It is supposedly advertised with a 170 degree FOV. The apparent included angle was 60 degrees, the most narrow of all.
The third photo is the video scene on the Tview display from the Boyo 200. Although it had different specs on FOV on the website, the box said it was 140 degrees. The measured included angle was 100 degrees, the widest of all.
The fourth photo is the video scene on the Tview display from the Boyo 420. Again, the websites have different numbers for the FOV, but the box says it is 170 degrees. The measured angle was 75 degrees.
The Boyo 420 is the clear winner. First, the video quality is much better (CCD vs CMOS) and the included angle is less than that of the Boyo 200. Since I want at "rear view camera" instead of a "backup camera", I want a narrow included angle. You might want a wider angle if you were backing up. The 420 is acceptable on the included angle, although a smaller angle would be better.
I had to do extensive modifications to the Boyo 200 mount that actually holds the cylinder tube that the camera is mounted in so that it would slide directly into the space where I mounted the camera in the top of the rear window. The Boyo 420 mount fit without much modifications.
Even though the 420 was the best of the cameras that I have, I still don't think it is good enough. If someone can find a better one, I would like to try it. I have ordered a Boyo vtl420HD. Don’t let the HD fool you, it is not real HD, but it supposedly has 600 TV lines and 640x480 pixels, and a 170 FOV (same as 420).
The next question that I had was the display, since the display might be the weak link. To verify this, I connected the 420 directly to a 32 inch HD TV. The fifth photo is the 420 displayed on the real TV. The TV image is better, but the camera is still not good enough for me, and I would like to have a better display and camera. Any suggestions?
The last two photos are how I mounted the camera.
-Bob Woods
I now have three cameras and have made a preliminary evaluation that I wanted to pass on since there seems to be some interest in this and I suspect some of you are making decisions now. Perhaps this will give some insight into this subject, although I don't consider this the final solution.
The first camera is the one that came with the Tview RV808. It is advertised as a 1/3" CMOS camera with 628x582 pixels, 420 TV lines, 2.0 lux.
The second camera is the Boyo VTL 200.It was advertised as a CCD camera but when I got it, the box said that it was a 1/4" CMOS camera with 640x480 pixels, 380 TV lines, and 0.5 lux.
The third camera is the Boyo VTL 420.It is a 1/4" CCD with 512x480 pixels, 420 lines, 0.3 lux.
The first photo is all three cameras with the Tview at the top and the 420 at the bottom.
I was confused with the field of view, FOV.As I learned, the FOV is related to the size of the sensor and the focal length of the lens. I find FOV to be a misnomer because the so-called FOV does not really correlate with the "included angle of the video scene" which I will call the "included angle" (my word). I measured the included angle by measuring the width of the scene in the display and the distance back to that width and then used the inverse tangent of that half angle and then doubled it.
I have tested all three cameras for their clarity and included angle.
The second photo is the video scene on the Tview display from the Tview CMOS camera.It is supposedly advertised with a 170 degree FOV. The apparent included angle was 60 degrees, the most narrow of all.
The third photo is the video scene on the Tview display from the Boyo 200. Although it had different specs on FOV on the website, the box said it was 140 degrees. The measured included angle was 100 degrees, the widest of all.
The fourth photo is the video scene on the Tview display from the Boyo 420. Again, the websites have different numbers for the FOV, but the box says it is 170 degrees. The measured angle was 75 degrees.
The Boyo 420 is the clear winner. First, the video quality is much better (CCD vs CMOS) and the included angle is less than that of the Boyo 200. Since I want at "rear view camera" instead of a "backup camera", I want a narrow included angle. You might want a wider angle if you were backing up. The 420 is acceptable on the included angle, although a smaller angle would be better.
I had to do extensive modifications to the Boyo 200 mount that actually holds the cylinder tube that the camera is mounted in so that it would slide directly into the space where I mounted the camera in the top of the rear window. The Boyo 420 mount fit without much modifications.
Even though the 420 was the best of the cameras that I have, I still don't think it is good enough. If someone can find a better one, I would like to try it. I have ordered a Boyo vtl420HD. Don’t let the HD fool you, it is not real HD, but it supposedly has 600 TV lines and 640x480 pixels, and a 170 FOV (same as 420).
The next question that I had was the display, since the display might be the weak link. To verify this, I connected the 420 directly to a 32 inch HD TV. The fifth photo is the 420 displayed on the real TV. The TV image is better, but the camera is still not good enough for me, and I would like to have a better display and camera. Any suggestions?
The last two photos are how I mounted the camera.
-Bob Woods
Attachments
The Mobius camera system has been getting good reviews from the motorcycle crowd.
It is inexpensive and adaptable with multiple lens options. They sell cables to allow the lens to be detached from the camera body so you could get creative with the mounting.
Check it out ---- http://stores.ebay.com/eletoponline365/Mobius-ActionCam-/_i.html?_fsub=6055299015
Mobius Actioncam Full HD Sports Camera 1080p 30fps 720P 60FPS Pocket Camcorder | eBay
It is inexpensive and adaptable with multiple lens options. They sell cables to allow the lens to be detached from the camera body so you could get creative with the mounting.
Check it out ---- http://stores.ebay.com/eletoponline365/Mobius-ActionCam-/_i.html?_fsub=6055299015
Mobius Actioncam Full HD Sports Camera 1080p 30fps 720P 60FPS Pocket Camcorder | eBay
This camera seems to have a lot going for it. I have been looking at the site
http://mobius-actioncam.com/
and have asked a few questions which I should have the answers to by hopefully this afternoon. This has to be the most open web site on a camera that I have seen so far. This camera is one rugged unit. They have a video of one on a RC car that is in a race as an RV setup going over jumps and rugged terrain. They have many ways to set this unit up and lot of choices to choose from. They even have a video comparison setup that allows you to see the various setups with the same scenes in side by side setups(4 camera shots, different lenses and same firmware for a good comparison).
https://vimeo.com/72618045
The prices on this unit are reasonable($97-122) Lots of mounting options(cross bows to magnets). They have apps for the camera as well(I-Phones to Androids and Macs). Lots of reading, references, and links. You can spend a good afternoon going through this site. Looks promising.
Bill
http://mobius-actioncam.com/
and have asked a few questions which I should have the answers to by hopefully this afternoon. This has to be the most open web site on a camera that I have seen so far. This camera is one rugged unit. They have a video of one on a RC car that is in a race as an RV setup going over jumps and rugged terrain. They have many ways to set this unit up and lot of choices to choose from. They even have a video comparison setup that allows you to see the various setups with the same scenes in side by side setups(4 camera shots, different lenses and same firmware for a good comparison).
https://vimeo.com/72618045
The prices on this unit are reasonable($97-122) Lots of mounting options(cross bows to magnets). They have apps for the camera as well(I-Phones to Androids and Macs). Lots of reading, references, and links. You can spend a good afternoon going through this site. Looks promising.
Bill
Ray and Bill,
The Mobius looks great and will be a competition to the GoPro; however, it is a camcorder and not a camera with a video output.
New Camera
I don't know why we can't get a high definition rear view camera. I bought the Boyo VTL420HD that was supposed to have more lines and a better resolution. What a disappointment. First of all, HD must stand for "heavy duty" not "high definition" even though it said it had more resolution. The 420HD does have a metal mount instead of the plastic mount of the normal 420, thus, HD.
To be fair, I think my unit was faulty since the buttons didn't work and the auto video features didn't appear to work. The other problem is that is it has the widest FOV of all. Compare this photo with those in my post #192. I will try to return this one and use my previous Boyo.
-Bob Woods
The Mobius looks great and will be a competition to the GoPro; however, it is a camcorder and not a camera with a video output.
New Camera
I don't know why we can't get a high definition rear view camera. I bought the Boyo VTL420HD that was supposed to have more lines and a better resolution. What a disappointment. First of all, HD must stand for "heavy duty" not "high definition" even though it said it had more resolution. The 420HD does have a metal mount instead of the plastic mount of the normal 420, thus, HD.
To be fair, I think my unit was faulty since the buttons didn't work and the auto video features didn't appear to work. The other problem is that is it has the widest FOV of all. Compare this photo with those in my post #192. I will try to return this one and use my previous Boyo.
-Bob Woods
Attachments
From Mobius site - "Video: 1080P 30FPS FULL HD, 720P 60FPS, 720P 30FPS HD, H.264/AVC1 video codec, .MOV file format.
Live TV video output while recording videos with optional TV-out cables "
Ray,
Well then, that will work.
-Bob Woods
Well then, that will work.
-Bob Woods
Hi Doc,
how about Google glasses? You can link to a Camera over your phone and see your 6 even when you turn your head, always have "an eye on it". Actually link two cameras, one in front and one in the rear. Record a 30min patch and if you are involved in an accident, you have a build in black box right in your phone.
how about Google glasses? You can link to a Camera over your phone and see your 6 even when you turn your head, always have "an eye on it". Actually link two cameras, one in front and one in the rear. Record a 30min patch and if you are involved in an accident, you have a build in black box right in your phone.
Bill and Ray,
I ordered the Mobius with the video out cable. It may package well. I'll let you know.
Pete,
Google glasses might be a good option too.
-Bob Woods
I ordered the Mobius with the video out cable. It may package well. I'll let you know.
Pete,
Google glasses might be a good option too.
-Bob Woods
Glad to hear you’re going with the Mobius Bob.
I understand your frustration with the choices you have made so far. You know the technology exist for a very clear, detailed view with a camera/monitor combo – but the actual HD quality views are not considered important by most manufactures.
I understand your frustration with the choices you have made so far. You know the technology exist for a very clear, detailed view with a camera/monitor combo – but the actual HD quality views are not considered important by most manufactures.