Performance question: Under chassis aero package....Is it worth it?
#61
Tech Elite
iTrader: (34)
Was looking at something here: In the results, I took the time difference between fastest laps and mulitplied them by the total number of laps in the fastest qualifier: Justthought that the results were a little supprizing:
Manny had a difference of .609 seconds X 17 laps = 10.353 seconds
His faster qualifier was by 10.2 seconds
Randy had a difference of .499 seconds X 18 Laps = 8.982 seconds
His faster qualifier was by 8.43 seconds
My difference was .392 seconds X 19 laps = 7.448 seconds
my faster qualifier was by 7.678 seconds
Manny had a difference of .609 seconds X 17 laps = 10.353 seconds
His faster qualifier was by 10.2 seconds
Randy had a difference of .499 seconds X 18 Laps = 8.982 seconds
His faster qualifier was by 8.43 seconds
My difference was .392 seconds X 19 laps = 7.448 seconds
my faster qualifier was by 7.678 seconds
#62
rcfoolz, you have pm.
#63
#64
More testing Sunday at Superior Hobbies, working on a configuration changes, effects of removing the middle piece, making adjustable tuning of the diffuser had some nice results.
The track was smooth and tight, but had a nice flow, but still a challenge. I like the parking lot track of Superior because it creates some unique challenges for running nitro cars. One part of the track that creates issues for some racers is a small ridge in the parking lot that is right after the turn off the back straigt. It likes to upset the car and it breaks rear traction and spins out. You either have to slow down or use the outside wall to keep the car moving in the right direction. (pvc pipe track layout, its the SOFT WALL)
Instead of putting on the softest tires you can get, and make a lot of changes to the car to try to keep the rear of the car from sliding around, I tuned the diffuser. The grip level of the track is excellent for rubber tires, but sometimes, what is good for rubber, isn't always good for foam tires.
Tuning the diffuser was a thought that If I could lower the diffuser down, closer to the track, I could create more rear grip without "dragging" it around. under the car. After talking to someone that I hope to work on this project to bring it to the market, he had mentioned something that is done to "tune" the diffusers on F1 race cars. With this fresh on my mind, I found that by lowering and rasing the diffuser as much as .5mm makes "HUGE" differences in the way the car handles. Like anything else on a race car, everything you chage makes a difference on how the car handles.
My findings: (first though, the term "grip" will be used, but it is downforce that makes makes the grip)
The lower the diffuser is to the ground, to a point, the more rear traction is created. Also, the more level the diffuser is, makes a difference too. When the inside if the diffuser is lower than the outside, less "grip" is created, but when you level the diffuser, "grip" increases A LOT, and it makes it less likely to break that grip when moving over a rough surface. (like that bump)
The second thing that I noticed about runnign a diffuser was that, the slower you run, the less effect is has.( thats almost a no brainer, right?) Well, without the diffuser on, I couldn't make the sharp turns quite as fast and it gave the car much more forward grip coming out of the corner. After a little change, the lap times dropped from the 13's to the 12's and even made it once into the 11's..
Again, I realy like the way the car feels with the diffuser. I know that those that have been following this, THANK YOU for taking the time to read this. And please understand why I don't have the photo's up right now, as I am working on getting this into the racers hands. I don't want someone to "step in" and make a diffuser that does not work the way this design works. If that was to happen, those that are intersted would just say that these don't work and that would be the end of it. Thanks again for following this thread.
The track was smooth and tight, but had a nice flow, but still a challenge. I like the parking lot track of Superior because it creates some unique challenges for running nitro cars. One part of the track that creates issues for some racers is a small ridge in the parking lot that is right after the turn off the back straigt. It likes to upset the car and it breaks rear traction and spins out. You either have to slow down or use the outside wall to keep the car moving in the right direction. (pvc pipe track layout, its the SOFT WALL)
Instead of putting on the softest tires you can get, and make a lot of changes to the car to try to keep the rear of the car from sliding around, I tuned the diffuser. The grip level of the track is excellent for rubber tires, but sometimes, what is good for rubber, isn't always good for foam tires.
Tuning the diffuser was a thought that If I could lower the diffuser down, closer to the track, I could create more rear grip without "dragging" it around. under the car. After talking to someone that I hope to work on this project to bring it to the market, he had mentioned something that is done to "tune" the diffusers on F1 race cars. With this fresh on my mind, I found that by lowering and rasing the diffuser as much as .5mm makes "HUGE" differences in the way the car handles. Like anything else on a race car, everything you chage makes a difference on how the car handles.
My findings: (first though, the term "grip" will be used, but it is downforce that makes makes the grip)
The lower the diffuser is to the ground, to a point, the more rear traction is created. Also, the more level the diffuser is, makes a difference too. When the inside if the diffuser is lower than the outside, less "grip" is created, but when you level the diffuser, "grip" increases A LOT, and it makes it less likely to break that grip when moving over a rough surface. (like that bump)
The second thing that I noticed about runnign a diffuser was that, the slower you run, the less effect is has.( thats almost a no brainer, right?) Well, without the diffuser on, I couldn't make the sharp turns quite as fast and it gave the car much more forward grip coming out of the corner. After a little change, the lap times dropped from the 13's to the 12's and even made it once into the 11's..
Again, I realy like the way the car feels with the diffuser. I know that those that have been following this, THANK YOU for taking the time to read this. And please understand why I don't have the photo's up right now, as I am working on getting this into the racers hands. I don't want someone to "step in" and make a diffuser that does not work the way this design works. If that was to happen, those that are intersted would just say that these don't work and that would be the end of it. Thanks again for following this thread.
#65
You have mail
#67
Update: Pictures....
the first 2 pictures are of the unit installed on an NT1 and the third is showing the design of the upkick angle without the fins. In the first pictures, the "fins" that hang down, have not been trimmed down, so they look a little rough, but after a little trimming and runnin in, they form up well.
Although the design of this has been optimized with tuning of the unit by testing different upkick angles, with some input to a person who ran at the Bumod Nationals this weekend, did some testing of thier own design.(Hope I put that in the right text) I hope he puts his comments here on rctech, "but unfortunetaly our race committee didnt allow me to use it." he told me.
pics removed.................
the first 2 pictures are of the unit installed on an NT1 and the third is showing the design of the upkick angle without the fins. In the first pictures, the "fins" that hang down, have not been trimmed down, so they look a little rough, but after a little trimming and runnin in, they form up well.
Although the design of this has been optimized with tuning of the unit by testing different upkick angles, with some input to a person who ran at the Bumod Nationals this weekend, did some testing of thier own design.(Hope I put that in the right text) I hope he puts his comments here on rctech, "but unfortunetaly our race committee didnt allow me to use it." he told me.
pics removed.................
Last edited by rcfoolz; 06-26-2009 at 12:49 AM.
#68
Yes, it was me who ran it this weekend at Turkish nationals at bumod race track. It really settles the rear of the car down, allowing to drive much harder, and having throttle earlier out of the corner. When race committee saw it, they didnt allow me to use it, so I had to remove them before the race
I had made it from a Protoform Speed 12 bodyshell.
I had made it from a Protoform Speed 12 bodyshell.
#70
Tech Initiate
Yes, it was me who ran it this weekend at Turkish nationals at bumod race track. It really settles the rear of the car down, allowing to drive much harder, and having throttle earlier out of the corner. When race committee saw it, they didnt allow me to use it, so I had to remove them before the race
I had made it from a Protoform Speed 12 bodyshell.
I had made it from a Protoform Speed 12 bodyshell.
My double deck diffuser will be ready for 3rd leg haha
#71
I was hoping to have this produced but it does not look like it is going to happen. Bummer! So for now, If anybody knows someone that would be willing to produce these, I would like to be contacted by them. The ideal device would be made from injection molded plastic.
1nsane: what was the .3 seconds?
1nsane: what was the .3 seconds?
#72
Tech Champion
iTrader: (22)
Honestly, you should just make a vacuum mold.
http://www.smooth-on.com/
The above site has materials for making a negative of the parts, which you can then back pour with the correct epoxy for a mold. All the end user would have to do is cut the parts out. It would be such a small mold that you could pull them yourself.
BTW, this thread inspired me to make a diffuser for my F103 Tamiya car, which actually works. I did not think it would do anything, but back to back running proved it did.
http://www.smooth-on.com/
The above site has materials for making a negative of the parts, which you can then back pour with the correct epoxy for a mold. All the end user would have to do is cut the parts out. It would be such a small mold that you could pull them yourself.
BTW, this thread inspired me to make a diffuser for my F103 Tamiya car, which actually works. I did not think it would do anything, but back to back running proved it did.
#74
Tech Initiate
I was hoping to have this produced but it does not look like it is going to happen. Bummer! So for now, If anybody knows someone that would be willing to produce these, I would like to be contacted by them. The ideal device would be made from injection molded plastic.
1nsane: what was the .3 seconds?
1nsane: what was the .3 seconds?
I have an F103GT with Tamiya NSX body and ABC diffusor. I'm gonna try it with 35 shore foam tires ( rears 30mm ). Gonna send the pictures soon.
#75
The new Roar rule book does not have a section for this, but the old books said that if the real race car had it, have a picture of it in use and it was ok. I don't know if this still stands or not.
With a basic wind tunnel (made from a large box of straws and some cardboard,) it gennerated 5gms of additional wieght to the front tires on each side and 11 grams of weight at about 45mph wind (based on stihl backpack blower ratings) on each side of the rear. More with a stronger air flow and less with less air flow. (tested both ways, with and without aero package. 3-5% increase in downforce. HAS NOT BEEN TESTED ON TRACK IN A RACE CONDITION.) So, does it work,? Hoping to do some track testing this weekend if the rain holds out in Tampa.
With a basic wind tunnel (made from a large box of straws and some cardboard,) it gennerated 5gms of additional wieght to the front tires on each side and 11 grams of weight at about 45mph wind (based on stihl backpack blower ratings) on each side of the rear. More with a stronger air flow and less with less air flow. (tested both ways, with and without aero package. 3-5% increase in downforce. HAS NOT BEEN TESTED ON TRACK IN A RACE CONDITION.) So, does it work,? Hoping to do some track testing this weekend if the rain holds out in Tampa.
Great job, for sometime now I've been wanting to create a windtunnel, but never had the time or means, care to share to to do so?
-Thanks
-Tino