Insane Speed Run car almost complete
#92
The body is made except for the back. The intended body shape is in B4maz's Avatar in green. It is neither cup nor GTP. It does look like it is very low drag. The run will be in a straight line on a dragstrip. Now that I can mention the ground effects, that is what will keep this body, which may have some lift without ground effects planted to the ground. The ground effects should kick in strongly at 100 mph plus. It will be concentrated to the back of the car. A front diffuser could be added as well though. The actual shape of the top surface of the tail may change from testing. I don't believe any bodies that you can purchase will withstand the high speed. That is why this one is in fiberglass. I realize other bodies could be used as a form for the fiberglass. We discussed a collapsible wing for speeds below 100 mph. I get termendous traction gains on my pan car when the rear wing kicks in after only about 15 feet out of a corner.
John
John
Here is the underside diffuser:
#93
The body is made except for the back. The intended body shape is in B4maz's Avatar in green. It is neither cup nor GTP. It does look like it is very low drag. The run will be in a straight line on a dragstrip. Now that I can mention the ground effects, that is what will keep this body, which may have some lift without ground effects planted to the ground. The ground effects should kick in strongly at 100 mph plus. It will be concentrated to the back of the car. A front diffuser could be added as well though. The actual shape of the top surface of the tail may change from testing. I don't believe any bodies that you can purchase will withstand the high speed. That is why this one is in fiberglass. We discussed a collapsible wing for speeds below 100 mph.
John
John
Sorry, part of the post with the bodies was'nt meant for you. Meant to be for the others that were commenting on gtp or cup cars . It didnt come across correct.
I know the lexan bodies wont hold up, you can back pour any body and make a mold and lay a shell from what ever material you want. The best thing about it is you can modify the shape and add directional finns, exhaust's, wicker bill's, etc....
You would be surprized that the ground effect's work around 25 to 30 mph, I have used ground effects back in the day with the wide pancars. I ran for a company wich Art Carbonell was a driver/owner ( vicfor ). We tested different configurations of GEffects, and they created suffecient force to notice the lapp times change with and without. We are talking 1/2 sec difference in lap times on a track that had 50 x 100 ft diamenssions, somewhat flowing. Sorry I cant remember any of the actuall info we wrote down.
One Thing I do recall is that we got the cars to corner and be more stable then when we ran the extra wing . Guess your wondering how old I am! LOL!
37. I started in 85, pancar is KING!
Hector G.
Last edited by speedxl; 06-13-2007 at 10:48 AM. Reason: NONE JA!
#94
Tech Elite
iTrader: (27)
Hector-Are you the guy that came down and drove my pan?
I tried ground effects on my wide pan just recently. I got no effect. Report and pics on the Pantoura thread. The design was similar to Nick's picture but there are some key differences. I run a soft dam in the front to keep the front end planted on some bumps that occasionally send the 1/8 scale cars airborne on the straight. The soft dam did not allow sufficient air under the car to activate any noticeable ground effects. I also did not have a full belly pan or side dams on the diffuser like on nick's car to reduce leakage. I imagine his will be more succesful than mine because of these two design differences. It would be nice to get some real benefit at around 50 mph. Thanks for the report. You are just a young pup then.
I tried ground effects on my wide pan just recently. I got no effect. Report and pics on the Pantoura thread. The design was similar to Nick's picture but there are some key differences. I run a soft dam in the front to keep the front end planted on some bumps that occasionally send the 1/8 scale cars airborne on the straight. The soft dam did not allow sufficient air under the car to activate any noticeable ground effects. I also did not have a full belly pan or side dams on the diffuser like on nick's car to reduce leakage. I imagine his will be more succesful than mine because of these two design differences. It would be nice to get some real benefit at around 50 mph. Thanks for the report. You are just a young pup then.
#95
Tech Elite
iTrader: (9)
b4maz,
I don't think I mentioned anything really about the amount of deformation to the nose of the body..but moreso the amount of downforce generated at the proposed speeds.
as far as GTP, NASCAR, etc...type bodies as someone mentioned... unless that is the class you wanted to set a record for...I'd be more intune with looking at shapes and designs used on the dry lake beds..and salt flats.
NIC ran a couple of his "STRAIGHT LINE" cars on at our VELO insane run...they were a handful, but pretty fast considering he had to run LEFT..
I'm not sure what/where you are building your car for (July at FONTANA?)
I do know for last years rules they had something about bodies having a simulated "drivers cockpit" on them (Don't know why...)
The carbon fibre body on your website...looks really cool, and I like that shaping a lot...
I don't think I mentioned anything really about the amount of deformation to the nose of the body..but moreso the amount of downforce generated at the proposed speeds.
as far as GTP, NASCAR, etc...type bodies as someone mentioned... unless that is the class you wanted to set a record for...I'd be more intune with looking at shapes and designs used on the dry lake beds..and salt flats.
NIC ran a couple of his "STRAIGHT LINE" cars on at our VELO insane run...they were a handful, but pretty fast considering he had to run LEFT..
I'm not sure what/where you are building your car for (July at FONTANA?)
I do know for last years rules they had something about bodies having a simulated "drivers cockpit" on them (Don't know why...)
The carbon fibre body on your website...looks really cool, and I like that shaping a lot...
#96
ground effects
hey Vic4
i too have run pan cars from day one. luv them. still run them but have to run nascar type bodies.
by the way i do not suggest that nascar nor gtp bodies are the way to go. my point is that too much down force will slow the car, I beleive jon and his crew are addressing this with their custom made bodies.
I too used to run an underbody diffuser or wing at the old ranch pit shop. It may have created some push. but not much.
I tried it recently at the velodrome. it worked at speeds under 50 mph. things change at speed over 50. for what ever reason I started getting lift above 50 mph. I have siince made changes.
as far as the hi speed runs, the carbon/ fiberglass one off bodies are the way to go. and the only real way to go is to make the areo test in a wind tunnel.
the wind tunnel is available for those who can afford it. it has been posted somewhere on this forum. for now i'll stick to lexan with little struts to prevent deformation on the nose and rear wing because my sponser can only afford these methods.
I hope to acquire a pantoura type chassis for next season.
I will be look at the crc, darksides and MLP designs.
I really am dissappointed that the hi speed run at Fontana and the SWtour velo race fall on the same day. but I will attend my own hi speed runs at the velo.
see you at the races.
wn
i too have run pan cars from day one. luv them. still run them but have to run nascar type bodies.
by the way i do not suggest that nascar nor gtp bodies are the way to go. my point is that too much down force will slow the car, I beleive jon and his crew are addressing this with their custom made bodies.
I too used to run an underbody diffuser or wing at the old ranch pit shop. It may have created some push. but not much.
I tried it recently at the velodrome. it worked at speeds under 50 mph. things change at speed over 50. for what ever reason I started getting lift above 50 mph. I have siince made changes.
as far as the hi speed runs, the carbon/ fiberglass one off bodies are the way to go. and the only real way to go is to make the areo test in a wind tunnel.
the wind tunnel is available for those who can afford it. it has been posted somewhere on this forum. for now i'll stick to lexan with little struts to prevent deformation on the nose and rear wing because my sponser can only afford these methods.
I hope to acquire a pantoura type chassis for next season.
I will be look at the crc, darksides and MLP designs.
I really am dissappointed that the hi speed run at Fontana and the SWtour velo race fall on the same day. but I will attend my own hi speed runs at the velo.
see you at the races.
wn
#97
Good use of Boeing resources
Sure beats sending tax dollars and Marines to Bagdad.
#98
LOL, so you think I was doing this at work? This is all stuff I do in my spare time. I mentioned that I work at Boeing to let people know my background in aerospace engineering. (I know you're trolling and trying to make this political since this has nothing to do with the speed run whatsoever, hopefully everyone ignores your post). Lets stay on topic.
Last edited by b4maz; 06-14-2007 at 12:08 PM.
#99
Project Updates
I fixed the problem with the throttle. You no longer have to hold brake to keep the car from moving. Neutral is Neutral. I had to reprogram the speed control so it didn't autoprogram throttle position. The car is more punchy, but you don't have to hold brakes to keep it from moving. I also put the .024" springs on the front end. These are the stiffest front springs Associated makes. This helped significantly with the chassis scraping. It also didn't make the car as twitchy in the steering. I saw John Stranahan's post on the longer front suspension travel for the front end. It might seem like something I should try out.
I ordered a whole spring set for the 10L4. It comes with all the different stiffnesses of VCS micro shock springs and main shock springs. I noticed that once my car is at speed the rear end becomes very mushy, like the chassis wants to keep rolling. I'm thinking about putting much stiffer springs on the VCS side shocks. I believe this would help offset the rolling. Or try anti-roll bars, but I'm not sure how I would attached them. I also ordered a whole set of TC4 springs. They come in much stiffer rates. I can experiment with those. I also ordered a Futaba 3PM 2.4ghz transmitter. This should give me much greater range.
Hopefully I can get out testing this weekend. We'll see how the weather cooperates.
Last edited by b4maz; 06-14-2007 at 01:01 PM.
#101
Tech Elite
iTrader: (9)
...the back end of that w/ the big motor, etc. looks to be very heavy...
if you are running the associated type micro vcs shocks, you may want to not only consider the heavier springs, but maybe install some softer front type progressive springs on the shafts themselfs (inside the regular springs), and/or maybe a short piece of rubber fuel tubing to use as a soft shock stop.
Same with the center spring/sock setup...
I will look and see if I have any HARDER front springs than the .024's.
The old HPI front ends use to use a lot heavier spring, because they were mounted further inboard..and had more leverage on them..so they went stiff to get the same feel as a .020-.022.
I'd loan them to ya, but I'd need them back if I can find them (cause I don't get rid of ANY of my old HPI stuff)
if you are running the associated type micro vcs shocks, you may want to not only consider the heavier springs, but maybe install some softer front type progressive springs on the shafts themselfs (inside the regular springs), and/or maybe a short piece of rubber fuel tubing to use as a soft shock stop.
Same with the center spring/sock setup...
I will look and see if I have any HARDER front springs than the .024's.
The old HPI front ends use to use a lot heavier spring, because they were mounted further inboard..and had more leverage on them..so they went stiff to get the same feel as a .020-.022.
I'd loan them to ya, but I'd need them back if I can find them (cause I don't get rid of ANY of my old HPI stuff)
#102
...the back end of that w/ the big motor, etc. looks to be very heavy...
if you are running the associated type micro vcs shocks, you may want to not only consider the heavier springs, but maybe install some softer front type progressive springs on the shafts themselfs (inside the regular springs), and/or maybe a short piece of rubber fuel tubing to use as a soft shock stop.
Same with the center spring/sock setup...
I will look and see if I have any HARDER front springs than the .024's.
The old HPI front ends use to use a lot heavier spring, because they were mounted further inboard..and had more leverage on them..so they went stiff to get the same feel as a .020-.022.
I'd loan them to ya, but I'd need them back if I can find them (cause I don't get rid of ANY of my old HPI stuff)
if you are running the associated type micro vcs shocks, you may want to not only consider the heavier springs, but maybe install some softer front type progressive springs on the shafts themselfs (inside the regular springs), and/or maybe a short piece of rubber fuel tubing to use as a soft shock stop.
Same with the center spring/sock setup...
I will look and see if I have any HARDER front springs than the .024's.
The old HPI front ends use to use a lot heavier spring, because they were mounted further inboard..and had more leverage on them..so they went stiff to get the same feel as a .020-.022.
I'd loan them to ya, but I'd need them back if I can find them (cause I don't get rid of ANY of my old HPI stuff)
Thanks for lending a helping hand with the springs. My background is racing 1/10th off road for about 10 years and this is the first on road car I have ever built and driven. There are so many things that the on-road and oval guys have been teaching me.
#103
Tech Addict
iTrader: (10)
Yes, the motor is 740 grams (about 2 pounds). I have to tweak the suspension a lot to get it to work correctly. No one has ever used a motor shaft as the rear axle (as far as i know), so experimenting is key! lol
Thanks for lending a helping hand with the springs. My background is racing 1/10th off road for about 10 years and this is the first on road car I have ever built and driven. There are so many things that the on-road and oval guys have been teaching me.
Thanks for lending a helping hand with the springs. My background is racing 1/10th off road for about 10 years and this is the first on road car I have ever built and driven. There are so many things that the on-road and oval guys have been teaching me.
#104
Also speak to the drag racers these guys run almost 90-100mph on a 132ft. and in the past they have done speed runs too. They can help you with setting up your car to go strate as an arrow and help you with your rear suspension set up, etc... You can go to rc rods.com, Grandmotorsports and speak with Mike Ogle or RAE Roy Anderson, IMDRA drag racing site where one of there guys, Rain man broke a record this year at over [email protected] second with brushless and lipo set up,them guys will be real helpful even with the side dams to the body of your car and things like that. Good Luck and Take Care...
#105
Tech Addict
iTrader: (10)
Actually I have been talking with Bill Poisso from LiteSpeed Engineering. He helped me figure out a way to attach the hubs to the motor shaft. My initial design involved some custom hubs that would fit on the 8mm shaft of the motor. Instead of spending 600$ each on custom CNC hubs, he came up with the idea of turning the motor shaft down from 8mm to 1/4". Then I could use off the shelf hubs for significantly less $$$. Thats what I ended up doing. If you notice the motor shaft in some of the pics, you can see that it has a little ridge when the shaft comes out the motor. This is where the diameter of the shaft changes from 8mm to 1/4"