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Discussion Starter #1 (Edited)
We've been testing a NOVAK 17.5 motor while searching for a B/L motor to use with the 3200 Lipo Peak/Orion battery. Our tests show the 17.5 motor is just too hot to replace the current STOCK 4 cell class.

We held the 3rd event of the 07 SWTour Series Saturday at the newly reopened METRO R/C SPEEDWAY in Bakersfield CA. This 280 ft. HIGH Banked Concrete Tri-Oval is the only CAP tire short track in CALIF.

Test Pilot for todays run was JOSH SMITH - from Team KGB Racing.

Josh was put in the Stock Class for the first round of qualifying - although the motor looked really strong in the early practice runs.

In this first heat, with a calculation for gear ratio based on a number I created for this motor based on the known rollout for the 4300 times and gear ratio, Josh came out of the box with the following results.

56/5:02.54 Josh Smith
51/5:01.33 Tim Twyman
51/5:03.15 Dane Hopkins.

The 51 lap run of Tim Twyman was the actual stock TQ after the first run, and the 17.5 LIPO had it 5 laps down on it's maiden run.

Compare lap times (First 10 laps)

17.5 / STOCK
5.15 - 6.01
5.28 - 5.92
5.14 - 5.81
5.08 - 5.69
5.24 - 5.70
5.20 - 5.84
5.36 - 5.80
5.30 - 5.82
5.22 - 5.70
5.18 - 5.71

Last 5 laps

5.47 - 5.91
5.45 - 6.19
5.36 - 5.94
5.30 - 5.79
5.39 - 6.23

So it was obvious that the 17.5/LIPO was TOO HOT for Stock...once again. So we moved JOSH to the 4300 class in the same round of qualifying...

Josh simply recharged the LIPO pack and had the car ready for the 4300 heat...which he won with his 58/5.03:25 to John Miles 57/5:03.00. After the first round Josh with his 17.5/Lipo was faster than the 4300 class TQ - Scot Petitclerc (Our last test pilot) which ran a 58/5:05.26

Here are some sample lap times between Josh and Scot.

First 10 laps of their 1st runs.

17.5/4300
5.13 - 5.27
5.13 - 5.19
5.14 - 5.36
5.06 - 5.12
5.07 - 5.15
5.11 - 4.96
5.14 - 5.05
5.25 - 5.33
5.08 - 5.12
5.07 - 5.10

And the last 5 laps

5.33 - 5.10
5.39 - 5.20
5.35 - 5.15
5.27 - 5.16
5.34 - 5.60

In the second round, Josh and the test motor picked up to a 58/5:02.87, but smokin Gary Hamilton stepped up the 4300 TQ time running a 60/5:01.44. Hamilton spent most of the race running high 4.8's and low 4.9's, while Smith was able to run a few 4.9's but spent most of his time in the 5.0 - 5.1 range.

The third round times almost mirrored round two, Hamilton stepped the TQ to a 61 lap run going 61/5:03.

Josh would qualify 4th in the 12 car field while Hamilton took the TQ spot.

In the main Josh pulled the tallest gear of the day, his times dropped off from 5.0's in the early runs to a consistant 5.2 from Lap 2 to the final lap on 57 with a handful of high 5.1's in the mix.

Hamiltons car also dropped a little speed in the main running mostly 4.9's and 5.0's with a 8 car field.

Smith's steady hand and collision avoidance ability let him beat Hamilton who got collected in a crash on lap 9. The hard charging Hamilton was able to pull of a 2nd place finish just 2 seconds behind Smith.

NOTE: Gary Hamilton pretty much OWNS the METRO track in Bakersfield. He's been the dominant MODIFIED driver and set the bar pretty high for the 4300/10.5 class as well. He spend a lot of time refining his setup and gearing for the 4300. Smith came in Saturday morning - I handed him the motor and told him where I wanted him to start the gearing, which is where it stayed most of the day. Smiths car seemed to have a slight push through the corners and I feel if we could have resolved that we would have seen his times equal those of Hamiltons. (Maybe we'll get Hamilton to do the next TEST w/ this motor) Josh also mentioned the balance of the car with the lighter lipo never felt quite right...and since the lipo is about 2/3rds the weight of a 4 cell pack we may have simply needed to add a couple oz's of lead weight to the LH side.

We're looking forward to testing a NEW motor from NoVAK soon, but will continue to test this 17.5 as well. I think this motor will make a great cross over motor to mix with the 4 cell 4300 class to allow LIPO's to run in nearly perfect harmony.

ADDED: I almost forgot - The TQ for the STOCK Class, set by DANE HOPKINS a 52/5:02.62 with lap times mostly in the 5.6 range.
 

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Thanks for the detailed information Joe.

First a little background to expand on 4300. I've raced many many times at this track only a couple of years ago. I definately understand, and have had cars, that handle and are super competitive here. Gary Hamilton is the undisputed west coast ruler of this track, so it's understandable that he was able to show up the field at this race. Scott Peticlerc told me that he has only run at the track a handful of times in the past. So based on prior experience I should have landed in between these two, which is exactly where I ended up.

However my car was never handling at the level that I would consider good. The push that my car had all day was definately holding me back, 1-2 tenths in my opinion. If I had cured this problem I estimate that I would have been right on pace with Gary, who's car looked excellent.

On the note of weight, I ran the car without adding the extra 3.2 ounces necessary to reach the normal 40oz weight requirement (my car came in at 36.8oz). As you can imagine, adding 3oz is a LOT. However I wonder if all of that weight missing from the left side of the car was the reason that I couldnt seem to cure my push, and also if it was part of the competitiveness of the motor.

I ran 39/100 which seemed to be the best gearing, compared to Gary who was running 41/100. I don't recall the rollout offhand, but we both ran an "L" and "R" tire in the rear. it should be something close to 3.1


In the end, I feel this test was extremely succesful in showing that with the power of lipos a 17.5 is ridiculously too fast for stock, but should end up being a very close match for 4300. If I could alleviate my push without adding any extra weight then I feel that this motor would be perfect to allow people to make a transition to LiPo without having to make a seperate class, because they should be able to run with the 4cell 4300 guys. On the other hand if the push is cured by adding 3oz of inside weight, part of the gain in lap times may be erased by the extra mass to accelerate.
Hopefully we can do a test where we run a car with the full 40oz, though i hate to contemplate adding that much weight to cars unless its really necessary.


Finally, I want to comment that I truly see LiPo's as the wave of the future. I cant emphasize enough how much nicer they are than regular packs. The convenience of running my car then throwing the pack back on the charger, and never having to worry about my battery is so liberating :) It gives me so much more time to work on my car, but most importantly to hang out and talk to people!!!

THanks for the oppurtunity to test this motor joe!
 

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Discussion Starter #3
Josh,

I forgot to write down what kind of recharge the battery took - If I remember correctly it was 1300 - 1400 mah correct?
 

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Discussion Starter #5 (Edited)
Stoneman,

That has not been the focus of our testing so it's never been on the track with anything but LIPO's.

We might give it a try, once we find the STOCK equivilant type motor we're looking for.

I would bet it would be a lot closer than the 13.5 is w/ 4 cell. But it would be a RPM dog. I would guess on 4 cell the loaded RPM would be between 8500 - 9000 rpm.
 

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We have been looking forward to a brushless motor that would be equivilant to the speed of a stock motor. we tried the 13.5 when it was in testing but it was 2 laps faster.
 

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Discussion Starter #7
Stoneman,

Are you guys receptive to the LIPO battery deal? If you are, when we are finished with what we are looking for we're hoping for equal speed to stock - maybe just a very slight tick slower by out test guys...because we KNOW setup and experience WILL make them faster..so we don't want to kick it off as a faster class...

I do think the 17.5 would probably be just about right as a 4 cell stock replacement other than the low rpms which would make some people cringe.
 

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swtour said:
Stoneman,

Are you guys receptive to the LIPO battery deal? If you are, when we are finished with what we are looking for we're hoping for equal speed to stock - maybe just a very slight tick slower by out test guys...because we KNOW setup and experience WILL make them faster..so we don't want to kick it off as a faster class...

I do think the 17.5 would probably be just about right as a 4 cell stock replacement other than the low rpms which would make some people cringe.
I don't think we are even close to lipo here in FLA.But we are hoping to change one day.

When you test it with four cell please post what your findings are. inquiring minds want to know.
 

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Stoneman, If I am misunderstandy you just say so, but there is no such thing as a "4 cell" LiPo pack. the closest there is is a 7.4 volt pack (two cells). That is why we are working with the "motor" to find one that will react as close as we can to the Stock times you run today.

Once this motor is found, it will only work well with the LiPo pack so I hope that you guys will be open to giving all this new stuff a try.
 
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