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Old 01-05-2006, 05:17 AM   #16
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so i can get the dos verions from the website and it will have all the gearing features and can save data ?
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Old 01-05-2006, 05:59 AM   #17
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Yes, but the DOS version may or may not with Windows 2000/XP.
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Old 01-05-2006, 06:07 AM   #18
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I use the dos version with all features on ly computer running WinXP , you may have to select compatibilty mode if it gives you problems
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Old 01-05-2006, 06:51 AM   #19
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Quote:
Originally Posted by SA_Racer
The following is one of my favourite motors, I recon this would be a screamer accoring to your standards Erok . I will apreciate your thoughts on this motor and perhaps you can also post some pics of a motor that you have found to be good in Stock.
Sorry dont have any screen prints.

The 100 watt benchmark that I use at 18-26A is for the Trinity Monster motor. Its tough to get an Epic Roar stock motor that high but if you do it should be killer on the track. One thing to note though is I race oval.
You can get a P2K to hit 111 watts+ at that mark but they get hot and fall off at the end of the run otherwise the P2K would be the best stock motor on the planet for oval cause of the power they produce but the heat factor makes a Monster or Epic roar stock a better choice.

I like to See max torque of 80 on the main screen for a Monster.
RPM at torque step 30 above 26,500, they usually scream if you hit that mark too. Once again for Monster and Epic Roar stock.
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Old 01-05-2006, 09:15 AM   #20
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Quote:
Originally Posted by SA_Racer
Thanks What range would you be looking at for normal stock racing?
I first measure the average amp draw in a race. You need a battery dischage device like a turbo 35 or its equivalent. Most guys that own one will let you use theirs to run the test as they might have an interest in the result as well.

I'll repeat this post here for convenience.
Here is the quick formula to calculate average amp draw from John Wallace

Average Amp Draw =
(Milliampere-hour x 3.6)/Race Time (in seconds)

You have to cycle a pack and get its capacity in milliampere-hour (mA-h). You do this on a Turbo 35 or similar device. Then run the same fully charged pack in the race. Discharge it, as immediately after as possible, on the T35 to get the mA-h remaining. Subtract the amount remaining from the packs capacity. This is the value you put into the formula above and the amount your car used in the race.
On an oval this average amp draw and close by, is a good area to explore on the dyno. Use maybe a 5 amp range higher than the average amp draw.

on a Road course, the slower parts of the track, while the car is accelerating, will have more effect on lap times. Take your readings at the average and greater amp draws. use maybe a 10 amp range higher for a flowing course, maybe a 20 amp range higher for a tight course with good traction.


amperages less than the average are of less interest as the car is going at costant speed or decelerating. Power here is not so important.

Thanks for posting your good motor. It would help to know what kind of stock motor it is and what motor springs you are running.
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Old 01-05-2006, 09:46 AM   #21
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John
Can you do the amp draw equation if you dont know your mah.
Say your pack is a 400 second runtime pack on the GFX cycle and you run the pack in 19T and it comes off the discharge with 100 seconds left. So if I used up 300 seconds in a 4 minute run can you give me my amp draw?
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Old 01-05-2006, 10:30 AM   #22
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You can do it with seconds, but you have to know the amperage that you are discharging it at. Explain the GFX cycle to me. It sounds like a varying amperage cycle. In which case select a constant amperage cycle. Say you have used 300 seconds at 10 amperes in a four minute race then the average amp draw is
Capacity in Ampere-seconds/ Racetime in Seconds
(10 x 300)/ (4 minutes x 60 seconds/minute)= average
300 A-s /240 s
12.5 amperes = average.

Now I just made these number up for sake of an example. Its actually easier to calculate average amp draw with amps and seconds rather than milliampere-hours.
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Old 01-05-2006, 11:24 AM   #23
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John I use 35 amps for cycling. so the 400 seconds is at a 35 amp cycle.
Then after a race I use 35 amps to discharge so I came off with 100 seconds with a 35 amp discharge down to 3.6v.
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Old 01-05-2006, 11:26 AM   #24
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So using that formula
I should take 35 amps x 300 seconds used / 240 seconds = 43.75
that seems kinda high for 19T 4 cell oval racing.

I have to be missing something
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Old 01-05-2006, 12:58 PM   #25
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400 seconds at 35 amps is 14,000 A-s

14,000 A-s x 1000mA/1A x 1h/3600s = 3888 mA-h battery

Are you using a battery with this much capacity or is the 35 amps merely the highest amperage in the QFX cycle and it is discharged at lower amperages some of the 400 s.

My GP 3700 batts are only showing about 3100 mA-h on discharge.

We have to pin down what that GFX cycle is. What discharger are you using. I can find out.

yes the amps are a little too high, but the capacity is pretty high for NiMH as well. I ran some dirt oval with a 9 turn quad and got pretty high average amperage, but it was only 30 amps. I did not have full traction, though.

Last edited by John Stranahan; 01-05-2006 at 01:45 PM.
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Old 01-05-2006, 01:15 PM   #26
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John,

The motor I posted was a Monster, running Putnam Grn/Grn Brushes both drilled. The springs are red both sides with the red on the pos side tweaked to be slightly harder.

Its late here now so im off to bed, Ill try post some pics of a epic tomorow. Ill apreciate if anyone here can post some similar stats of their good motors for comparison purposes.

thanks for your feedback. ill do some calculations and try determine my amp draw.

till later

Last edited by SA_Racer; 01-05-2006 at 01:55 PM.
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Old 01-05-2006, 01:18 PM   #27
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All i am doing is cycling my pack on a Turbo 35 GFX at 35 amps

Cycle - 4 cell pack of IB3800's
Peak 1- 6 amps. .02 drop
120 sec delay
Peak 2- 6 amps .01 drop

Discharge at - 35 amps on the Turbo 35 GFX
Results: 400 seconds of runtime
Not sure the mah cause I never record this value.

Then I charge and run the pack in 19T 4 cell oval and after my run I throw it on the Turbo 35 GFX (at 35 amps) and hit discharge and usually has 100 seconds left in the pack. Once again I do not record mah
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Old 01-05-2006, 01:43 PM   #28
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Is it a 4 minute run (240 seconds) or 5 minute (300 seconds). Use the one that's appropriate for your race. Sorry if I confused the issue with my test data. Wish I had those IB batts. I understand the GFX is the discharger now not the name of a particular cycle.
SA racer- Thanks for the motor info. I would say 122 W peak power at 32.6 amps is a good stock motor for oval. The power is band shifted toward lower amperages and is still quite high.

Last edited by John Stranahan; 01-05-2006 at 04:59 PM.
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Old 01-05-2006, 02:06 PM   #29
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we run 4 min races

so is the calc right then 43.75 amps ?

Typically my voltage packs cycle 385-400 runtime with 4.78-4.80 volts and 8.0-8.2 IR
And my runtime stuff 415, 4.75, 8.4

Honestly while I am sponsored I dont think my stuff is all that special.
unless I am being lied to I am hearing top oval guys getting 4.84-4.87 voltage at 35 amps for a 4 cell pack.

My buddy who I can trust his numbers had an off the shelf IP3800 pack go 400, 4.82, 8.0 last week. Sad part is that pack had the worst labels, he didnt want to cycle the higher numbered packs.
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Old 01-05-2006, 02:28 PM   #30
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John, Erock, those are pretty common numbers for the IB3800's and of the IP3800's latest batches.

Nice eh?
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