hey guys, i just got my b4 together and i went with a 31t pinion and a 75 spur.. does this sound about right? tekin 17.5

Could work out if you are new to 2wd. You prob wanna get some extra pinions/spurs from 32-34 and 69-72

you will get around the track, but you won't be fast. If you are racing against guys who are good stock drivers, you'll think they are cheating. There's that much of a speed difference in the setup you posted.

I say leave it be until you can go 5 min without getting marshalled. Then go 34-35 / 69

ok thanks, how big is the difference in 34 and 35?

That is going to assist you in fine tuning it to your layout, the difference between what you have now and this is huge though.

i haven't even ran my buggy yet, i just got it put together.. i dont want to say im a expert driver, but im not beginner either.. wanting to run this buggy in stock class and mod. i dont want to be poochin around the track i suppose i am going to try the 69 34 and ill get a 35 as well and see what i think.

I suggest you grab 33,34,35,36 for pinions. This covers you for different layouts, different temp days, etc.... The difference between 34 and 35 can be minor or it can be huge. There's a lot of variables.

Remember, one misconception is that 17.5 class is a 'stock or beginner' class. In fact it's a spec class. If you want to go fast, you have to get the most of your gear.

Worry about all of that AFTER you are able to run consistently without wrecking. You can have the fastest car on the track and as soon as you blow one turn, you are in last. That's the nature of spec racing. Consistent beats fast every time.

Things you can do to generate more power, but mind you, everything comes at a price. Power = heat = wear :

-Tune your motor so that it is efficient and produces power without generating heat by adjusting the timing. I had someone with a 'motor checker/dyno' help me here. Every motor is different. For example my Viper motors are happy around 45 deg timing, where others may be better around 30 or 50, depending on the motors.

-Gear up so your car is max speed 3/4 down the straight. That is a starting point... tune up or down accordingly, keeping temps down below 150. The lower the better though.

-use higher C rated batteries, 60C+

-charge at a higher amp rate. 8-10 amps

Personally I would get some smaller pinions beginning because jumping in is like suiciding unless your easy on throttle till you learn your track.

i thought in 17.5 class you couldnt have any motor timing or boost? i see what your saying now with gearing, as far as batteries go i have a fantom 50c 5000 i am running in my b4.

i also have a 6500 120c fantom that i use in my scte?

i thought you could only charge the batteries per how many mAh your battery is

for example. 5000=5A

Not having it geared correctly from the start can issues as well. Just because it undergeared doesnt mean it wont get hot. Also it can be fairly frustrating to not be able to get through certain sections of the track if your gearing is way off.

You cant have boost through the speedo. You can adjust the timing on the motor though. Charging a 5000 at 5a is considered 1c charge rate, most batteries can do a 2c charge rate, that would be 10a, check with the manufacturer for more info.

some tracks boost and some dont. It is recommended to charge at 1c. But with days packs, if you need to charge at 2c, most of the better packs will do it just fine. If you are running ebuggy and need to charge a 4s 6000 mah pack, you might want to charge at 2-3c if you only own 1 pack. Or you can buy more packs and precharge them and 1c is fine. I would check with your manufacture before trying 2+ c rated charges. Some of the promatch/smc packs are rated at 3-5c.

bah, matt. you beat me to it.

sounds good, yeah i cant handle a pooch ass car, i have more thottle control and be consistent and know that the power is there than to know that the power isnt there you know? i just want the best setup i could possibly get. ill find it eventually. is there any other spur gears i should get once i get the 69?

or do i use all the different pinions with the 69t spur? such as 25-36?

As the other guys said, there are two ways to add timing.

1. Boost - this is done via the ESC
2. Mechanical - this is done via adjusting the motor's endbell.

MOST tracks run blinky, which means no boost on your ESC (light will blink to signify, hence the name blinky). You should clarify this with the track before you do anything because that changes your gearing and everything else.

50C batteries will be fine, but keep in mind the higher the better for when you want new ones. SMC makes good packs at a good price. I prefer shortys but thats up to you and your car.

Charging rate... most guys do say 5 amps for everything. My own charger only goes to 5 amps. But if you want to get the most power, you need to be able to charge at a higher rate.