I run my 17.5 with stock mechanical timing on 24/75 gearing. I use max timing starting at lower RPMs such as #5 or #6. With this I get great low end torque due to the gearing and the high amount of timing advance extends the band width of the motor for top end. I adjust the pinion and the timing based on motor temps after run. The Havoc Pro SC has a great feature to check temps. Just tap the set button after you run and you get a reading. I keep the temps to 160 degrees.

I would say that throttle control is critical for all racing conditions. Tuning you EPA, EXP, and Throttle frequency can effect that way you control the vehicle. I always felt that my truck was more capable than my driving.

Thats really interesting the way you run that. I never thought of trying that. Im wondering what would cause more heat, smaller pinion and higher timing or bigger pinion and lower timing.

Must do some testing. I have a small heat gun that i use to check temps. I think the set button feature just shows if you are close to the temp cut off.

Just out of curiosity, what type of surface do you race on?

I run this on most track surfaces. Indoor clay this works great for me.

When you gear high it reduces low end torque and increases top speed which can be good if your trying to improve wheel spin. In the Stock class this is usually not the issue. The truck will accelerate much faster with smaller pinions so that is the driver for my gear choice. Timing helps extend the range of the motor. So Dynamic timing is the enabler to allow me to reduce my pinion for low end and even extend the top end speed. It is always a balance for sure and you have to gear to the top speed of the track.

If you play with base mechanical timing you will see that if you retard timing you will reduce top speed and run cooler. If you advance timing you will increase top end and run hotter. With Dynamic Timing you can have the low end cool running AND the high end advanced timing. I have thought about even retarding motor timing and adding it back in with dynamic timing if temps were to much. Most of the time I can find a good medium.

I know that high speeds can cause heat but that can be managed by moving the ramp point in the ESC as well as pinion and timing level.

I think i might try this again then. Do you change anything with the throttle curve or drive freq?

My thought was to gear higher and run my dynamic timing set point to a lower rpm to give me acceleration.

Also the Havoc Pro SC temp readout has 5 levels of temperatures. The Red is the one that you definitely don't want to see. The Yellow and Green are the sweet spot.

If you increase the pinion and add timing this is like increasing the pinion more. Dynamic timing was added to expand the speed range of a motor. If you just add timing to your already optimized gearing you will certainly overtemp the motor. So you can reduce the pinion gaining mechanical advantage and extend the speed range to keep your top end. Also you will not be at top speed all the time so added heat you get is offset when you run a lower speeds because you are running cooler there. It's hard to explain but my set-up has worked for me. I usually have advantages on the straights and then it is up to my driving skills on the infield.

I do cut the bumper as well. Only the sides where the circle part is, so the mud flap section is still there. That is only so the body does not get hung up on it and starts to rub the tire....You can leave a small amount of tail light section and still get away with it ;)

great info man, thanks a ton...much appreciated. So you actually run timing at max and the set point really low like 5.5-6.5k rpm, so the timing makes up for the for running a lower pinon.

If i understand this correctly, wouldnt this make it hard to get traction to the rear wheels (since you have so much torque with the small pinon and the low set point?) Or do you just loosen the slipper or adjust exp from tx?

I used to run a Novak Kinetic that had current limiting which I set very low to control the torque at very low speeds. Now with the Havoc Pro SC I have to use EXP and really just finger control after that. I try to hold a low position through corners and just squeeze slowly. Slipper matters certainly. Punch control or other radio controls help. I run the Spektrum DX3S with the DSM2 receiver (SR3520).

If I encounter temps that are too high I will dial back the timing before anything else. High ambient temps are usually the challenging time.

So you just use the expo throttle curve...nothing on the tx itself?

cant wait to test this out, put on a 25t pinon and im glad i picked up a bunch more to play with.

weight
 

How are you guys adding weight. and where at on the chassis? pics would be great.

I went to Pep boys and asked for some tire weights. I have 3 on the left side next to my reciever, 3 in the back under the battery foam and 1 on the front bumper on the top plate.

i never saw this answered a few pages ago, just wondering as i plan on getting one of them.

I just rebuilt my SC10 diff with MIP outdrives and AE everything else. Carbide diff balls and my own special diff ring treatments. Its the smoothest diff I've ever built. The light weight AE outdrives haven't lasted for me.

Don't ask about the special treatment on the diff rings. That will start a discussion that will eventually lead to JMuck talking about lapping his balls.

Actually you can search the thread and find a decent amount of discussion on diffs. I use a lapping plate of 3/8" tempered glass with different grades of sandpaper stuck to it. I use one of the previously mentioned AE lightweight outdrives to lap each diff ring up to 800 grit. I think the technique is as important as the components to a certain extent.

so go with the mip kit?