Archive for April 2009
Tamiya Alfa Romeo Giulia Sprint GTA – Test Drive
Love this little car, built it over a year ago and was sitting on the shelf. So decided to take it for a spin, everything is bone stock, standard 540 tamiya motor I think it is 19 turn. The battery is intellect 4200, the tires etc are stock but almost brand new, love driving this thing.
This thing probably does not even hit 10-15mph but it is a lot of fun to drive, rear wheel drive chassis seems to be well balanced for taking decent corners at reasonably high speeds. The body is very detailed, I kind of wish I had built it in red color to begin with but oh well.
Mercedes Benz C11 – Finished Body
Looks like Tamiya is already out with this model, available at Amazon. It is a rear wheel drive and includes a finished body
I really enjoy building and tuning the cars more than making bodies.. so definitly would be interested in this vintage kit.
TA05 FPV Mamba Max Speed Passion 2.5R 50mph
Took the Ta05 speed passion 2.5R combo for a run as well, nothing changed on the car setup except for rear wing addition and FPV video gear. The car ran very well, as expected the added weight of the FPV gear made the car a little unstable at high speeds nearing 50mph.
I have radar tested this setup for 50mph in windy conditions along with rear wing, I would say it was pretty near that target given that it was not windy that day.
The video is more fuzzy on this car, I beleive this is mainly due to the car being setup lighter than the TC5R and so on corners and little bumps the car shakes more and thus causes more video disturbance..
I will hopefully be working on some kind of universal chassis of some kind that can hold the FPV gear better and definitly upgrading to 5.8ghz system when I can.
TC5R FPV Mamba Max 5700kv 60mph
So finally got around to test out the new motor/gear/25c lipo setup on the TC5r. It was an extremely hot day, average ambient temperature was about 90-96. The car performed well, but ended up blowing the left rear tire and crashing as a result
The Mamba Max 5700 combo 87/22 gearing with Trakpower 3s 4900 25c combo is very very good, I enjoyed running the car. However the FPV equipment it self is pretty heavy along with the 3s lipo made the car somewhat unstable at high speeds, I estimate the car was topping out at around 60mph I did not get a chance to use the radar gun to make sure but given the setup and my calculations it should be doing at least that much.
I intend to get an OSD setup soon and perhaps in time upgrade to a 5.8ghz video system so I get better reception, the whole project has been challening because there are a lot of moving parts. The video gear and the car the electrics all need to be setup well and mounted on the car so they dont make the vehicle unstable.
I think I’ll be doing this in phases, next one will definitly be the OSD so we can start seeing some data like motor temperature, RPM and of course GPS based speed.
New Formula 10 Kit from HPI
Looking pretty sharp, I have been thinking about building a new car. I think a formula 1 type car would be ideal, would be curious how it will perform considering it should weigh slightly less than most touring car kits.
Here is the link to HPI Racing Europe http://www.hpieurope.com/kit-info.php?partNo=102870
I am sure it will take time for it to make it to the US, but it is planned to be release in a kit form.
TC5R Motor selection for fastest race able 3s power setup
My digital camera seems to have come back from the dead some how, so thought I would write a post on what I have been up to.
I am currently working on selecting the best motor/esc/lipo setup for fastest 3s lipo race able car, so far I have tried the good old Novak 3.5R, the Mamba 7700kv and Traxxas 3500kv motor.
All three motors were run on the TC5R chassis using the VXL3S speed control, they all survived the 11.1v of power mostly because they probably were never able to exceed their rpm limits and perhaps with a lot of luck as well.
The problem is that the lower turn motors like the speed passion 2.5R run very very fast on 2s but seem to max out at or around 60mph. That is plenty fast for racing, but I just have the itch to see if we can go faster, maybe around 70-80 clean on top speed and still be reasonably racable.
The TC5R with the above motors sits pretty heavy and I have had to use harder roll-bars so it does not hit the ground everytime I make a fast corner. The over all stability seems better due to added weight but I still need a solid motor/gear combo that can give me over 60mph and be able to go around a large track without too many issues.
My plan was to order the Mamba Max 5700 system which I have installed and done some inital testing, everything looks good just hope the weather is clear this weekend so I can do some good test. Also this time around I plan to be in FPV mode, essentially a wireless camera mounted on the car so I can get a feel of the car and power as if I was actually sitting in it.
Speed Passion’s Wireless Power
http://www.redrc.net/2008/02/speed-passion-wireless-power/
I realize this has been around for sometime, but wondering if anyone used. I really like the idea but I doubt that it would be as powerful. Very interesting concept none the less
Broken camera equipment
Folks I have been out of commission lately due to broken camera, I have not been able to take video or still photos of anything so far.
Currently I am working on two projects, one finding and building the fastest 2s lipo race able rc car and I think I am almost concluding that project. Secondly, working on building the fastest 3s/4s brushless race able 1/10 setup, this one is taking up most of the time at the moment.
The fastest 2s so far is the Tamiya TA05 with mamba max and speed passion 2.5R, the car has been running amazingly with top end speed of about 60mph and totally controllable on a large track. The problem however is that even a 5400mah or 4900mah lipo pack runs out within 5 or so large track laps, I am looking for perhaps an 8000mah or maybe even a 10000mah pack to see if everything balances out, however at that point the question would become to effectively cool the motor so it keeps running efficiently, the mamba max is at around 120-130 at the end of a full pack so at this point not too worried about it.. but the motor tends to be 140-160
The 3s/4s setup is a bit dicy right now, I am using the TC5R as the chassis but can’t seem to find a good motor/gear/esc combination that can give reasonable run-time along with making the car as fast as possible. So far I am still running the VXL 3S as the esc but have tried Novak GTB 3.5R motor, Mamba Max 7700kv motor and the VXL 3500kv with mixed results.
The Novak GTB 3.5R obviously is unable to run more than 5 minutes with 3s, shuts down with over-heat and does not seem to hit it’s top end. The 7700kv does however seem to perform a lot better and longer run-time but lacks the torque that I need with added weight on the car so not really breaking the 50-60 mph barrier. The 3500kv motor seems very solid but I think it’s asking for 4s to get it going properly, so will have to see what happens.
I have ordered the mamba max esc, 5700kv mamba motor and the CC BEC. I will start experimenting with 4s setup on VXL 3500KV motor and surprisingly enough the folks at speed passion that their 3.5R 540 can is able to do 3S … I was really surprised but I have become a big fan of their electronics so will have to see that as well.
As soon as I get my camera equipment going again will start post pics and videos of my findings, stay tuned.
TA05 and TC5R Speed Runs

Since my Novak GTB 3.5 has blown up most likely due to gearing issues, I decided to upgrade the TA05 and TC5R to break my current 53mph record with Novak GTB and TC5R combination setup. So the first test was to run the TA05, it was a very windy day and I was also experimenting with HPI X-pattern wheel/tires on both cars so was not able to get my target 60mph top speed.
According to my calculations tha TA05 should have hit approximately 60mph, however clocked a clean 50mph (previous top speed 43mph) run using a Speed Passion 2.5R motor. This is a fantastic motor, not only does it have plenty of torque (using Trakpower 2S 5400mah 16c lipo) but an outstanding 13800 rpm/volt and it sounds awsome. I think if it was not as windy and I was not using the rear wing, I reckon I should have hit close to 60 but that will have to wait since I am waiting to receive a Trakpower 2s 4900 25C lipo pack.
The 4900mah 25C rating should give me 4.9 x 25 = 122.5 amps, currently with the 5400mah 16c I am getting 5.4 x 16 = 86.4 amps. The Mamba Max ESC is rated 100amps max so with the 4900 25c pack I should definitly get more torque and hopefully my target 60mph top speed.
In all I am very happy with the overall performance, the motor is very light and the TA05 with everything weighs only 1472grams. I think once I get the 25c rated lipo, I will do another speed run to try for 60mph again, hopefully it’s not too windy again.
The TC5R I decided to turn to a traxxas VXL 3S system that I had bought a while back, but never really used it much. The reason behind using this system was essentially research on the internet and realizing that I will need much more torque i.e. battery power to hit traget speeds of 70-80mph. And boy does this thing have some serious power, the motor is 3500kv and I am running 48p 75/35, since this is a low kv motor I am able to use trakpower 3s 5400 16c lipo.The car is definitly heavier but that is increasing general stability and straight running, the torque on this thing is so nice the car continous to wheel spin even when reaching higher speeds. The problem however during this run is that I was unable to do enough runs to actually clock the speed by my bushnell radar gun.

In only a two test runs I lost traction big time and the car flew about 4-5 feet in the air after hitting the grass. Fortunately there was no major damage, I lost the right rear suspension holder and the spur gear (kimborough spur) seems to have disintegrated, not sure if this was caused due to heat or simply got crushed due to too much power.





















