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Old 06-19-2007, 10:16 PM   #1471
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Note that Drew has posted a nice report on his RC10L with pics and a Video on the previous page.

So here is that Parma Lola body on my pan car. Note the fan. Reminds me of the Chaparral 2J "Sucker Car", CanAm car with two snowmobile engine driven exhaust fans that made 1500 lbs of downforce. More pics of the back of the Chaparral 2J.
My fan intakes possibly cooler more presurized air to the speed control. I might test it tomorrow.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-lola-235-mm-gas-body-resized.jpg  

Last edited by John Stranahan; 06-19-2007 at 10:35 PM.
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Old 06-19-2007, 11:17 PM   #1472
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Funny you showed that, I just tried mount a GTB on my car and thats what i was going to do lol.
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Old 06-20-2007, 09:44 AM   #1473
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I'd love to see what kind of runs you get with that - but I doubt it will be faster than the Toyota - it's just too much DF and drag. . .
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Old 06-20-2007, 11:59 AM   #1474
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Here is maybe a pic of the fullsize car or see the attached photo. The Lola T530 Can Am car on which this body is possibly modeled. It is very popular on the 1/8 scales. Someone may know of a better Lola.

Boomer-If you are right, it might be good on a loose track (my track most of the time). I am not so sure it is high drag as considerable portions of the body are lower than the GTP bodies that I have been using. I will probably not need a spoiler, though. I have mounted it lower on my car than on Drews. My front dam is thus shorter. The lowered center section hugs the upper A-arms inner pivot and hugs my electronics on the second deck. I had to put my small Spektrum Pro receiver back in to clear it. The body is wider in the front, but the frontal cross section may be similar to the other bodies. I imagine that the cockpit has been moved forward on the RC version to give the gas motors clearance for the cooling opening. It seems I need one of those side stiffeners the 1/8 scale guys use. My right side is out a bit.

John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-lola-t530.jpg  

Last edited by John Stranahan; 06-20-2007 at 11:43 PM.
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Old 06-20-2007, 05:31 PM   #1475
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Air temp 95F Track Temp 125F. Traction Poor

Power Capacitor on Novak GTB
I have added the bigger 8200 uFpower capacitor in tandem with the factory 5600uF. I put some big shrink wrap over the pair. I described this in a previous post. Here are the results.

This is what I noticed. The motor felt sluggish. Run time was good. Motor and speed control temps were 125F. Brand New Novak 3.5R geared 90/12 with medium sized tires. Traction was poor.

I geared up to 87/12. The motor felt better. Temps were the same.

I removed the big capacitor. The motor felt better still. Lap times were being announced and were .5 seconds faster on average than the previous run. The experiment was muddled because I was chasing Jeff in a Nitro car this time which I caught and passed until he hacked me. I filed a protest. Motor temp was still the same. There were no baby thermal shutdowns in any of the runs.

Now I wonder if Novak has detuned the 3.5R by using smaller wire or if my previous sessions runs with the 4.5R and the ovesized RC4less tires just gave me better traction on the straight. The low temps are hard to explain. More testing will tell. I am saving those tire for my speed runs with Nick.

Parma Lola T 530 vs Hot Bodies Toyota GT1
I ran these two bodies back to back. The toyota first for 3 runs then the Parma Lotus Nitro 235 mm body last. Here are some differences.

The Parma 235 mm body had tons more steering. Too much really. This can be explained by the wider front of the body. Our pan bodies typically run 212 mm at the front. This body is 235 mm. I did not try and tune the chassis to the new front downforce, but I did turn down the dual rate 3 times to take out steering.

I had some wiggle going into the sweeper with the Lotus that I did not with the Toyota. A small spoiler on the Lotus would fix this, but the built in spoiler is already as tall as my Toyota GT1's added Lexan spoiler. I wonder if the little holes and general untidiness of the added on side dams and spoiler on the GT1 helps stability in this regard. Kind of like real feather fletching on an arrow vs smooth plastic fins.

Top speed seemed to be about the same on the two cars. The cross-sectional area at the rear of the two bodies, The GT1 with an additional spoiler and the Parma without, are about the same installed on the car. The Lotus was squirrelly on the straight. This surprised me, but it is the same way that a 200mm Lotus behaved on my narrow Pan car.

On high g turns the rear end seemed a little top heavy and skipped rapidly just a little with the Parma Body. Only occasionally.

You could tune your car to run this body in a pinch. See Drew's Video. You could also use it to solve a chronic understeer problem you may have after trying different tires and different suspension setting.

John

ps. I note with sorrow that Stormer does not list the Toyota GT1 body at present. The HPI USA web site does not either.

Last edited by John Stranahan; 06-24-2007 at 01:05 PM.
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Old 06-22-2007, 06:18 PM   #1476
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Battery Tests at 20 hard, hot, high drain cycles

I restested the Thunder Power battery to rule out a battery problem with my 3.5R motor.

ThunderPower Battery at 20 cycles 3688 mA-h 7.17 V at a 20A discharge
ThunderPower Battery new 3950 mA-h 7.18 V at a 20A discharge

This is a 7% loss in runtime which is about the same for MaxAmp Packs after this many cycles and very little loss in voltage.

MaxAmps New 7.21V at a 20A discharge, 4238 mA-h capacity
MaxAmps after about 25 cycles 3905 7.14 This is a 7.8% loss in runtime (estimated 6% loss at 20 cycles)

The batteries are behaving very similarly at this point. A 1 % difference is less than the error in the treatment of the two brands.

Region 9 Fuel On-Road Regionals Test Session on Friday
The practice session, the day before the race, is a delightful time for me to test my pan car. Traction starts out poor but ends up close to medium by the end of the day. So my question for the day was: is this new 3.5R motor different than the last and is this a good or a bad thing? I also got some practice in with the new bushnell Radar Gun from Radarguns.com ($100 bucks shipped if you can believe it). See the pic below. This is mostly for my speed runs with Nick.

First run
Gearing 90/12 (my standard for my previous 3.5 R motor) I used the large RC4less tires to rule out traction problems. I used the recently tested Thuderpower pack. I got 9 minutes of run time. Motor and GTB Temps were 125 F. Track temp was only 105F or so. Well this is certainly more run time than I have gotten with a 3.5R and 3600 mA-h. Speed on the straight was less than before. Performance in the infield was absolutely outstanding like before. Well at this point I can call it a late model 3.5R. I would have to measure the wires to know for sure, but I don't have the older motor. It is slightly detuned from the old motor either by chance or on purpose by Novak. No thermal shutdowns. I have a remanufactured 3.5 R coming. It may or may not behave like this motor. Probably the lower temperature that things are running is a benefit for Houston with this late model 3.5 R.
Now I want to say that this car is not giving up anything on the straight to the Nitros 1/10 or 1/8, but I used to make some passes at the end with the old motor.

Second run
Gearing 90/13. Lap times were as good, but the motor felt more sluggish. I had a baby thermal shutdown for 1 second or so after 4 minutes.

Third run
I settled on 93/13 gearing rather than 87/12 so that I could use the bigger pinion. It worked well. No thermals. I was using short front tires by this point. The car was ripping up the 1/10 scale nitros all except for Binson. It passed a couple of spec class 1/8 scales. Brakes were very smooth. I am getting my braking rhythm back.

Fourth run
I used short front and rear tires at this point. Rears were at 2.30 inch fronts about .216 inch, about .1 inch over the plastic. The car was dialed. It ran its best laps for the day. I was .7 slower than the best ever, but they had used sugar on that day. Also that previous day I was sparring with Lyn's 1/8 scale spec class car. This chase always makes you go about .5 seconds faster. The pan car loves a sugar water treated track (and a chase).

Wheelies out of turn 8
I got some speeds with the Radar gun coming out of turn 8 and going into turn 9. My pan does this section about like a 1/8 scale, so I measured one of them. You come out of turn 8 fairly fast at about 20 mph. You reach a peak of 40 mph about 2/3 of the way down that little straight. I then use brakes to the apex and accelerate out tight. My pan car with the 3.5 motor will pull the front wheels off the ground at 20 mph coming out of turn 8 once in a while. This tells me I have the infield acceleration dialed in as fast as possible. Speeds at the end of the straight were about 54 mph with the traction that we had. We go into turn 1 at about 45 mph.

Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-bushnell-radar-gun-resized.jpg  

Last edited by John Stranahan; 06-22-2007 at 11:05 PM.
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Old 06-23-2007, 03:13 AM   #1477
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Here's my new chassis ready to build
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Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-chassis-klaar-van-frezen-1.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-chassis-klaar-van-frezen-2.jpg  
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Old 06-23-2007, 09:03 AM   #1478
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Looks good Mathijs.
I see youre using just one battery position now instead of 2 on the old chassis. Is the battery moved a little more to the front now, at least it seems so?
Looks like 2 different front trackwide and smaller cutouts on the chassis.
What else is different? Thicker chassis?
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Old 06-23-2007, 09:23 AM   #1479
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Indeed 1 battery position, slightly forward.
Batteries are also moved more to the middle of the chassis.
2 width frontend, regular and extra wide.
Rear pod revised to center brushless motor.
I also added a dampener front brace.
Main chassis and rear pod bottom plate are 3mm thick, the rest 2.5.
I'll post a picture when it's ready.
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Old 06-23-2007, 12:19 PM   #1480
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Mathijs-Nice work! Did you make any effort to eliminate the extended pinion?

Insane Speed Run
Nick and I had another session. I took my pan, little changed over the previous road race practice. I ran the new GTB 3.5 geared 93/13 same as on the track. It tops out on Mikes-Hobbyshop.com's straight. Nick was able to time a couple of runs topped out. 53 mph. Then probably because a fullsize car appeared on our test track the range on the radio changed. We had tested it previously at 130 yards. The range was reduced to 80 yards. The pan car went out of range. The GTB has a nasty habit of maintaining full throttle or medium throttle when it looses signal. The car also aplies left steering. TOTAL DESTRUCTION. The car hit a curb. The chassis is split from the 1/3 point all the way back. The Servo is ripped off it's mount loosing the ears. The servo saver is broken. The front Bumper which was glued on is broken. The battery is in quarantine. Here is a pic. Ahh the price of speed. Fortunately all the custom parts survived. This is my original Pantoura chassis that I have been running since the thread began. It was a little on the thin side near the back so it was not a great loss. I have its replacement in hand.

We had radio range and stability problems with Nicks car. The back end is still being fabricated.
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-total-destruction.jpg  

Last edited by John Stranahan; 06-23-2007 at 12:31 PM.
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Old 06-23-2007, 12:25 PM   #1481
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John,

I see that LRP has released a 4.0 motor that seems to be a compromise between the 4.5 and 3.5. I don't think it's delta wound, at least I didn't see it mentioned. Apparently it's more efficient than the 3.5 as well. It's an interesting development, which seems to fill a very small gap.

http://nosram.com/news.asp?id=58
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Old 06-23-2007, 12:29 PM   #1482
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Syndrome-It seems that this new Novak 3.5 turn motor is filling the same gap. It is more efficient than the old motor with slightly less top speed, but very good infield punch. I do have an LRP TC edition with 3.5 motor on backorder. Should ship anytime now.
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Old 06-23-2007, 02:58 PM   #1483
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Quote:
Originally Posted by syndr0me View Post
John,

I see that LRP has released a 4.0 motor that seems to be a compromise between the 4.5 and 3.5. I don't think it's delta wound, at least I didn't see it mentioned. Apparently it's more efficient than the 3.5 as well. It's an interesting development, which seems to fill a very small gap.

http://nosram.com/news.asp?id=58
Im pretty sure the LRP 4T is delta wound. Same is for the GM EVO 3 4T.
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Old 06-23-2007, 08:16 PM   #1484
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So this is what I understand about Novak winds. There are two solder points to each coil. There is a Solder Ring on the pinion end of the motor. This joins one end of all the three coils together. The other connection is at the back of the motor one for each pair of coils. By its very nature, then, you end up with 1/2 winds like 3.5 or 4.5. You start a wind at the back and finish at the front of the motor, giving the extra half wind. I am told you can put the solder ring at the back and have whole number wraps. I don't know if anyone does this.
I have just seen the inside of several motors. The trinity 3 wind motor does not have this solder ring on the pinion end of the motor. It is a y wind as stated by Trinnity just below. Coils start and terminate at the back of the motor. Definitely a different type of wind than the Novak.

Trinity N60 specs.
3 Turn Equivalent
Strongest Rare Earth Neodymium Magnets
Y Wind
Sensor Less
Meets all ROAR Specs
Sintered Balanced Rotor
Dual Precision Ball Bearings
Lead wires and connectors included, Leads soldered on N80

Picture on left: Non Pinion side of Novak Motor showing solder points for the three coils. Two adjacent coils share a solder point.

Picture on left middle: Solder ring on Pinion side of a Novak motor. All coils share this contact. This ring results in 1/2 winds.

Picture on right middle: Trinity N60 Y wind motor: shows no solder ring on pinion side. Just a paper insulator.

Mamba Max 7700 kV: very similar to the Trinity showing the three solder points on the non pinion side, one each attached to each lead. 1/2 turns are not possible. This is a Y wind just like the Trinity.

Now all this said there are dozens of ways to affect the power output and power band without changing the wind number. It appears that the Novak motors are quint or hex wind: six wires wound at once. You can change this. This changes the induction of the wind. You can change the gauge of the wire. This changes the resistance of the wind. They never tell us these very important parameters of the brushless motors. The Mamba and the Trinity motor are maybe dodecyls (12 tiny wires wrapped at once) Who knows. I did not count them.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-novac-3.5r-guts-resized.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-novak-solder-ring-cropped.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-trinity-n60-003-resized.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-mamba-max-7700-kv-guts-cropped.jpg  

Last edited by John Stranahan; 06-25-2007 at 01:37 AM. Reason: corrections after V12's post just below.
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Old 06-23-2007, 08:31 PM   #1485
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I was always under the impression that the Novak brushless motors were all Wye winds and that configuration is the only one that is ROAR legal.( also why they are 1/2 winds ie; 3.5,4.5 etc.) The Delta wind is not as efficient- Aveox brushless motors are all Wye winds for that reason. Then the Mambas are headed for Roar legalization- as per someone who works there in the maufacturers area of this forum. Don

Last edited by DLS II; 06-23-2007 at 08:55 PM.
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