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Old 04-10-2009, 07:35 PM   #316
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Default Lots of good info

Lots of good info here. Thanks to all who post their experience. I got a brand new TC3 a little bit ago (racer kit) and VTA caught my fancy. I started with a power train out of the parts box: older 27-turn, made three 4-cell packs out of two matched 3700 6-cells. Threw on the kit setup and went racin'. Jesus, was I slow. One of the guys lent me a "hot" 27-turn brushed and I still got smoked bad. Just installed the Novak 21.5 Havoc combo. Waiting for a Trinity 5000mah lipo and charger. Tested on the nice smooth tarmac in front of my house with a 6-cell IB4200 matched pack. Oooh yeah. Very quick with excellent acceleration. The best gear I could put together out of the toolbox is a 35/65 (48 pitch) which gives a 4.64 FDR. I'm waiting for a 60 spur to arrive which will give me 4.29.
I noticed that it took about 75-100 feet to reach top speed (just listening to the pitch of the drive train). That's longer than most of the straightaways in the area.

So the question is this: how far down the straight do you want to reach top speed? I race karts and formula ford and we would typically gear to carry redline for no more than about 5 seconds on a straight, which is more of an engine abuse issue than a speed issue. Are little cars just about the same or is there a different logic?
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Old 04-10-2009, 07:42 PM   #317
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Default Gearit for iPhone

BTW, if you have an iPhone, there is a cool app called "Gearit" which will give you FDR and rollout if you enter spur, pinion and tire diameter. It lists most touring car internal ratios by model, so it's simply a matter of picking your car and entering the numbers. I think it was 99cents. Totally worth it.

There's another called "CrossWeight" which gives you all the important weight percentages for your car. You need 4 scales to get the weights, but when you plug thme into the app, you get the F,R,L,R and cross weights and percentages. It works for all size cars. I think that one was $1.99.
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Old 04-19-2009, 08:38 PM   #318
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Default HPI Pro 4 VTA setup help

Looking for a good base set up for my HPI Pro 4... or a good recommendation from the HPI Set up sheets. I have the ability to run a front one-way, i don't have a spool.

Running outdoors on VERY smooth concrete, medium bite in the hot Florida sun. Tight, technical track.

At first i was loose upon corner exit, seemed i had too much torque and was spinning the tires. Shortened the front upper links and now i'm pushing something fierce. I'll post my complete set-up later but here's my shock set up...

Oil- AE 35 front and rear.
AE Green front springs/ AE Blue Rear springs

I tried switching these around and i also tried Blue on all four corners... the current set up feels like something i can work with.

The bad part is the basket ball court where i can practice has much better grip than concrete where we race... i can get a good set up on the basketball court but that doesn't translate to the concrete.

Thanks in advance!!
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Old 04-26-2009, 04:07 PM   #319
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Question about a Spool V.S One way. I decided to try a Spool in my VTA car but I didn't have my Oneway to compair it to. any VTA racers run a Spool? in one way it felt good on the slower turns but pushed on the High speed turn. Has anyone noticed a advantage to using a spool vs a oneway? I know the Sedan (13.5) run them but they got the power to "pull" the locked wheels. just your oppions on either staying with my one way or make the change to a spool
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Old 04-26-2009, 05:36 PM   #320
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From racing spec so long ago and VTA this once, if the fast line doesn't include any braking, choose the one way and keep the car rolling. The one way should give you the same power coming out of turns as a spool.
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Old 04-26-2009, 09:33 PM   #321
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From racing spec so long ago and VTA this once, if the fast line doesn't include any braking, choose the one way and keep the car rolling. The one way should give you the same power coming out of turns as a spool.
It sure was a intresting feal on how diffrent it handled. it felt verry fast but my lap times told a diffrent story. I think ill stay with my oneway
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Old 04-26-2009, 09:48 PM   #322
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It sure was a intresting feal on how diffrent it handled. it felt verry fast but my lap times told a diffrent story. I think ill stay with my oneway
IMO, I think it's a LOT easier to drive smoothly with a one way than a spool - smoother is usually faster regardless of how it looks. Every time I've tried the spool in my 13.5 rubber car it's like the setup is instantly way off as.
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Old 04-26-2009, 09:57 PM   #323
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Originally Posted by jhberger View Post
So the question is this: how far down the straight do you want to reach top speed? I race karts and formula ford and we would typically gear to carry redline for no more than about 5 seconds on a straight, which is more of an engine abuse issue than a speed issue. Are little cars just about the same or is there a different logic?
With the brushless setup, the major limiting factor is heat. Always check your motor temps a minute or so into testing a new gear ratio. No sense torching a nice new BL motor. I've seen 170, but 150 would be a safer limit.

Beyond temp, I usually look to top out about 3/4 down the straight. Then I will evaluate the slowest corners to see if gearing down a bit would provide better lap times.

If your track offers practice times, they'll become your best tuning instrument. The clock never lies!
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Old 04-29-2009, 09:46 AM   #324
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With the brushless setup, the major limiting factor is heat. Always check your motor temps a minute or so into testing a new gear ratio. No sense torching a nice new BL motor. I've seen 170, but 150 would be a safer limit.

Beyond temp, I usually look to top out about 3/4 down the straight. Then I will evaluate the slowest corners to see if gearing down a bit would provide better lap times.

If your track offers practice times, they'll become your best tuning instrument. The clock never lies!
Roger that. I went out and raced last weekend, brought my temp gun and got hip to the concept. Running a new Novak 21.5 and new lipo at 4.64FDR, I barely saw 125 on the heat gun. Ran in RCGT for the first time with a brushed 27 and 6-cell, ran a 5.31 FDR with that and got a 2nd degree burn when I picked the car up (about 185). The 21.5 seems to be all torque and it surprises me that it's so quick off the corner with such a tall gear. Thanks for the tip.
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Old 05-03-2009, 03:55 PM   #325
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Spool all the way. Most of the faster guys use the spool only because of the braking power. The brakes allow you to go hotter into a corner and stick your nose into the corner first when passing.

The "no brakes" one-ways also seem to encourage drivers to blast guys ahead of them when entering a corner because they can't adjust for the speed change. Because of this, I've seen many conversations about banning one-ways to minimize the "accidental" PIT maneuver.
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Old 05-03-2009, 07:08 PM   #326
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Spool all the way. Most of the faster guys use the spool only because of the braking power. The brakes allow you to go hotter into a corner and stick your nose into the corner first when passing.

The "no brakes" one-ways also seem to encourage drivers to blast guys ahead of them when entering a corner because they can't adjust for the speed change. Because of this, I've seen many conversations about banning one-ways to minimize the "accidental" PIT maneuver.
Ill admit I did that with my oneway just blast into the turn because you know you don't have brakes and you end up takeing out the outside driver in the process. obviously with a Spool its a completely diffrent driving style the fact that you got no "corner enter speed" hasn't hit me yet you almost have to use the brakes now
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Old 05-03-2009, 10:41 PM   #327
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When I switched to the spool from a one-way I had to re-work my car to compensate for the lack of initial turn in. You just can't plug-n-play.

With the spool, you do have to drive more agressively with the throttle. I almost never coast. Had to replace coasting with 25% throttle to help the steering.
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Old 05-04-2009, 09:02 AM   #328
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got 2 spools on order for my tc4s. I've just been running my front diffs tight in the mean time which as really helped on power steering.
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Old 05-04-2009, 10:11 AM   #329
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Ill admit I did that with my oneway just blast into the turn because you know you don't have brakes and you end up takeing out the outside driver in the process.
So you admit to being a Hacker?
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Old 05-04-2009, 03:27 PM   #330
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So you admit to being a Hacker?
Hello my name is Chris and I had a hacking problem it's always the "it looks like I can make it move" and if im geting it right with a spool you can't lift all the way going into a turn? like you always have to be on power for it to turn? I haven't had much time to test it and see what I have to do diffrent to drive it right
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