Hi,
I am very eger to build my own competitive rc car. I have purchased myself a HPI Sprint 4WD chassis from for $35. It has all of the wheels, tyres (with good tread) etc and lots of spares parts below are some pics of it:

http://www.flash-servers.co.uk/images/chassis1.jpg
http://www.flash-servers.co.uk/images/chassis2.jpg
http://www.flash-servers.co.uk/images/chassis3.jpg

I am wanting to know what parts i am needing to make this into a competitive electric RC car, i have a budget of about $100 to purchase used parts off .Please could you tell me all of the different compontents i need e.g. motors, batterys, reciever, transiver, speed controll box etc. I am wanting to set it up with mabe 2 high torque motors, will this be possible?

Thanks
Simon Tate :thumbsup:

I guess before I answer, I should ask more questions. How new to RC are you? Do you have any experience with ESC's, servo's, motor's, and reading over all the specs on them?

Do you have a local track that you wish to race at?

If your answer to my first question is that your just getting into RC and your knowledge is only just starting then you've got some reading to do. Give me an idea on your background and I'll try and supply you with some good links that will give you a nice overview on electronics, specs, tuning, and setup.

The hardest part of your question to me is that you have a roller in need of quite a bit to make it run yet your budget is $100.00 That's a very difficult thing to get done with such a small budget.

competitive.... as in racing on a track or as in outrunning the neighborhood dog?(two very different things. well not VERY, but kind of)

I wont be racing against others competiviley all im wanting to do is to have a good mess around with some mates, i am just getting into RC, i dont really have much knowledge of any of the electronics etc. I guess i could extend my budget to about $200

excellent, thats what I needed to know. What you are looking to do is I guess what most would call "bashing" as opposed to racing. Just generally getting out there and having a good time.


For some very good beginner information I recommend you take the time to read through this site.

Misbehavin RC Pit lane (http://www.misbehavin-rc.com/pit-lane/pit-lane.asp)

Read through the general RC articles as well as the General electric articles. It will give you good idea's on radio's, ESC's, motors, and basic tuning/maintenance issues.

Once you have a good understanding of the basics it will be much easier to ask questions on what your specifically looking for. With a limited budget I might also recommend you try buying some things used to offset the costs.

When you go to a used for sale forum such as hobbytalks or anyone elses always do a search on the person you are considering purchasing from. Search in the trader feedback portion of the forum. Get as much information as well as address and phone numbers. If the deal feels at all goofy back out and save yourself some headaches.

As far as directly telling you what parts you need, I'm not an on-road guy and I'm unfamiliar with your car and different gearing setups. Since you need all the electronics it might be nice to set aside specific amounts of money for each. ie: 25-40 servo, 35-50 ESC, 25-35 motor, ?? radio/rx and so on. That way you can set a value on the parts and just try and get the best you can get for your money.

As much as I hate to say it but this hobby is very difficult on a tight budget especially starting out. Don't forget about tools, batteries, chargers, etc....

Good luck and enjoy some reading. That site is easily written and well documented with pictures. Some of it may be specific to other vehicles but the principles are still the same.

ok, iv now read through all of the info related, below is a list of things ill need, please tell me if iv missed anything:

Motor
ESC
Servo
Batterys
Body Shell
Radio Gear

do you have a battery charger? Does it do nimh and nicd?

a m8 of mine has a Nicad battery charger and he says i can use his

Well iv just purchased a 10 Turn Obital Pro BB 2 Motor, a 10 Turn ESC, Im goining to be purchasing a Transiever/Reciever set with crystals, handset, reciever and 2 servo's included as a well a lamborgini shell to go with it all.

It is possible to upgrade parts on my current chassis (my HPI Spint RS) but i am little confused on what these things shall do. I can upgrade my shocks (pretty simple what they will do). And the gearing e.g. the spur gear, i currently have a standard 87 tooth woven graphite spur gear which is upgradable from 100 tooth all the way up to 122 tooth but i do not know if it will be worth doing this.

I wouldnt worry much about upgrading parts on the chassis. Unless you break a certain part often, then upgrade it to aluminum or a stronger material.

When you get the car up and running you will need to make sure to gear it right. Keep checking the motor temperature after runnig fr a few miutes. Getting a motor too hot will start to damage its magnets and brushes, which will slow it down and eventually ruin it. Over gearing will also get the speed control(esc) hot and cause damage. So you will need to read up on how gearing works to know what pinion gears to buy. Pinion gears are the one that go on the motor, in case you didnt know. Good luck!

Ok iv been reading a tutorial on how to find out what spur gears and pinion gears you need. At the moment i have a 86 tooth spur gear and i am going to get a 16 tooth pinion gear. Below is the link for the tutorial:

http://www.rcuniverse.com/magazine/article_display.cfm?article_id=506

From this tutorial i have worked out the following:

That i need a 110 tooth spur and a 16 tooth pinion gear.

If you are interested in working it out for yourself my max RPM is 41900