For the guys that have run 13.5 4 cell and now are running 21.5 lipo what are the differences in rollout?

We are running on a 120' carpet track 4-cell/13.5 rollout 2.85-2.95
lipo/21.5 rollout 3.05-3.20

Raymond

Wow... only one response for gearing on the 21.5BL/LiPo combo???

Depends on what speed control you are using, the size of the track, the tire size, carpet or asphalt, indoor or outside, the temperature of the track if it is outside, are you using a motor cooler. There are alot of variables.

242' Concrete high banked full stagger caps 1.60-1.70 gear ratio!

if your using a motor cooler do you add more gear to it or take it away.

Here's more info for ya. http://www.hobbytalk.com/bbs1/showthread.php?t=219013

What kind of rollout for 21.5BL/LiPo (20C Orion 2400/3200) would be more applicable to 17.5BL/4-cell speeds?

Or even more in line for a "Stock/Novice" class?

This is for Rosewood (Glenn's Hobby Corner in Goldsboro NC) and it is a flat carpet oval. I am not sure of the exact size... picture of the track here --> http://www.glennshobbycorner.com/16322.html

I am just getting started in Oval and pretty darn sure I am not ready for 13.5BL speeds yet.

Tim S.

Tim.. From some that have tested so far at The Wood. There already .1 faster than 13.5 4 cells with 21.5 lipo on a green track....;)

Thanks John... that is the problem with figuring this equation out. From what I herd, they were rolling out at 3.6 at RW (but those looked to be some of the "fast guys").

But as you can see some others posting on this thread (different tracks I assume) are stating that 3.05 - 3.20 rollout is equal to their 13.5/4-cell lap times.

I won't be going back to NiMh and I guess I can hope for SMC to succeed with their single cell LiPo... I just hope that RW will have a novice pan car class where I can get some laps in without being in everyones way LOL.

To start off I guess I will just have to start out with my Orion 20C LiPo's (2400/3200) and a lower rollout than most until I can get my setup and driving decent.

What are you finding in terms of the gearing window? is it pretty small or can you "miss" a bit and not be totally off pace?

What are you finding in terms of the gearing window? is it pretty small or can you "miss" a bit and not be totally off pace?

From my experiance the 21.5/Lipo combo has a pretty wide rollout range on smaller carpet tracks, I,ve ran 3.3-3.4 second laps ( thats a fast competitive lap at this track ) with rollouts ranging from 2.50 to 3.10 range on a 120" runline carpet track with motor temps in the 120-150 range.
On the larger 200ft+ Minnregg/SnowBird tracks I,ve been rolling out at 3.8-4.0+ with motor temps under 150.

On our 140' runline track its like this - race, go home, buy bigger gear, race, go home, buy bigger gear etc. Every time I gear up, I go faster. Now in the range of 3.6, motor temp about 130-140 - and that hasn't changed since I crossed 3.3.

On a 280ft flat asphalt track I ran 4.3 with good results.

is that how big our track is? I've wondered...I was going to roll it with a wheel, but I'm too lazy

is that how big our track is? I've wondered...I was going to roll it with a wheel, but I'm too lazy

Honestly, I was taking your word for it from the About Tracks thread

"Central Coast R/C - Nipomo CA
Flat Asphalt - Perimeter 110 x 90 (Run line approx 280 ft.)
Square (INDY STYLE) corners."

Oh sure use MY words...damn I thought you found something when I wasn't looking.

Mine is just a guess using length and width of lanes. It should be close...and WOW was Bryan's car undergeared when I looked at what we ran. (I still had the gear for HAVEN on the car which is only about 180 ft)