Just to add to his point, don't make both changes at once. Spend some time working with PWM and then go back to 16,000 (starting point) and then spend some time with punch. Once you get a feel for how they translate to on track performance, you can start to work with both.

I can tell you that I have always been a fan of 100% punch coupled with 16,000 mhz on medium to low bite tracks. If I am spinning the wheels too much I back down the punch 5-10% at a time until I get it right.

When grip is a bit higher, I feel as though 16,000 mhz is too soft. I will drop down to 8000-9000 mhz range while keeping 100% punch. In order for you to find your sweet spot, just start at 16,000 and 100 and then drop down one step at a time until you are happy.

Does brake Pwm have the same effect on temps as throttle Pwm?

Haha sorry for all the questions guys but looking to get rid of the temps issue then effectively power up from there, so one more:

If I find with the Lower motor timing and smaller pinion that I now have not enough speed on the straight, is one way to end up with a middle point on this to then bring in a small degree of advanced timing on the esc (say 10 degrees) to kick in at a highish rpm, so it only brings it back on the straight?

Thanks!

Very good points, thank you for the extra guidance.

Yes, the higher the PWM frequency the higher the temps will be, but the smoother/softer the brakes will feel. So far I am finding that I like lower brake PWM frequency with a lower percentage of total brake. This works to transfer weight and slow the car without being so strong as to unsettle the rear of the car in 2wd. I don't have enough time with 4wd to say if it is good yet, but I used the same brake settings as my stadium truck with my 4wd buggy and I do like it.

DaveG - the brake settings can have an effect on the esc temp but not as much on the motor temp. Motor temp is more driven by gearing, throttle settings and run time. And also on some 4wd buggies, air flow from any holes put in the body. If you are running a lower turn motor (I think I saw you post before 6.5), you might want to have a hole or two for air flow as well.

Nick is spot on with the vents and gearing. Assuming that your gearing and air flow are correct, I would try adding some top speed timing first. See how it feels and how it temps out after about 3 min. If you have the speed and the temps are good, let it cool and run for 5 min. Check again. Rinse and repeat until your temps get over 150 OR you hit 10 min run time.


The rest of my boost settings if you like.

5 deg max timing
5000 rpm start 15000 rpm finish
2 slew rate
10 deg top speed timing

I would be SUPER, SUPER careful about running boost in 4wd with a lower turn motor. It really shouldn't be needed. Go on YouTube, find the 4wd Worlds videos from last year. Lee and Travis did not run boost in 4wd mod, on that track with the long straights and jumps. Just geared it right, legal size vent holes (I think they can only be 10mm, forget).

Just trying everything basically!

I had air vents but I have slightly made them larger and also added an air guide inside the body, as the main air vent sits higher than the motor...my guide now directs it on. Having said that, the air coming through the gap,for steering licks goes straight on to the motor anyway.

Have also lowered pinion (I am now 1-2 teeth less than others running the same motor wind of 6.5) and further lowered punch and brake strength (I use brakes heavily and had them at 100). I have also lowered motor timing 10 degrees.

I also have 2 fans on order to sit alongside the motor, because unfortunately my air recents won't do much good when I can't have them at some events!!

I really want to get the temps well done before Cactus, as last year the 40 degree ambient increase compared to my previous running directly fed a 40 degree motor increase and I cooked my motor good and proper!

What I would like to do this time is find a way of being at 120-130 after 5 minutes, then instead slowly bring settings back up until I have the right temp/performance balance. I do fear my next run at motorama first practice will be like running 17.5 though haha!

Generally speaking is there a rule of thumb on how much temp difference a gearing change of just one or two teeth makes, and also for running fans?

I appreciate all the help guys!

Just want to point out I think Bob was correct about the high speed and my issues with the glitching. I had no issues tonight racing!

Thank you so much!

Ok, I checked the stock Profile #2 settings were at 100 punch and1900hz. Should I or should I not be in Blinky?

Sorry, screwed up and was in profile1the whole time! Still gettin used to this System.Lol

Glad I could help

I run blinky mode for everything 99% of the time. I prefer it over boosted setups.

100% punch and a low pwm freq should feel very snappy. If you still want more, I suggest swapping rotors to the 12.8mm rotor (not legal for 17.5 ROAR racing!) and adding the pro6 cap.

http://www.shopviperrc.com/ProductDe...ode=8VSPVSTR04
http://www.shopviperrc.com/ProductDe...ode=6VSPCAP007

Just checking how it works, if I remove 10 degrees of timing from the motor, then add 10 degrees top speed timing on the esc, that just means at top speed am I back where I started and elsewhere I am using the lower timing?

Not exactly - its not a 1:1 ratio difference, using boost/timing through the esc will generally create more energy/power, which will also create more heat. Yes, running at places like Cactus in AZ or CA in the heat does generate some extra concerns, its always a compromise to find the balance between speed, power, and heat build up.