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finallyfox075

Project 51, new bits, old bits, tech bits help please

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Hi everyone,

So 29 years after my parents purchased a Tamiya Hornet and so very badly wanting a Fox, I finally have one. Its in pretty ordinary shape, could have found a better car I'm sure but it came with the box and most of the original packaging. Now for the rebuild.

Its not destined for the shelf, its not going to be rebuilt strictly from original 1985 release parts, probably 58577 bits to be honest. I've purchased a re-re Wild One for my daughter whos shown a love for RC so It will only be a weekend runner. I dont care about breaking stuff, i'l just fix it. So, I've ordered a truck load of new parts, all tree's, parts and screw bag as well as heaps of alloy and upgrade parts such as a Thorpe ball diff.

Now for my questions, and bear with me cause its been 30 years since I played with a Tamyia. Lipo, brushless, 2.4ghz radios etc werent around in my time.

1. The upgraded Thorpe diff should handle more power but do I go with a traditional brushed motor or step up to a brushless system? and if so any recommendations on a kv? or If I stick with tradition how may turn motor? What are the better motor esc combos in both options. There's plenty of combos (motor/esc) around the $150 AUD mark but whats worthwhile and what will likely go up in smoke.

2./ A lot of esc's these days are forced cooled, any recommendations of cooling mods given the Fox's closed body design?

3./ To go lipo or not? I guess the power system needs to match the drive system. I'm chasing more torque and power increases and looking for more run-time from whatever system employed.

4./ Is there a decent charger capable of charging multiple battery types?

So in closing, I'm looking to build a quick, reliable Fox with decent run-time.

Lastly, a quality dependable radio and receiver combo. Thanks in advance guys, I'll post progression photos as parts start to arrive and its rebuilt.

Cheer Daniel.

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If that chassis is from a re-issue Nova Fox, then be prepared that the steering servo mounting holes are in a different place because of the changes to the steering servo saver. Since it's not for the shelf, you can re-drill the holes and plug the ones you are not using, or swap to the Nova Fox steering setup, so no big drama.

I would stick with the standard gear diff rather than swap in a Thorp unit. The Thorp ball diff (apart from being very expensive and rare) will actually handle less power than the stock gear diff. Use AW grease in the gear diff for a stiffer diff action.

The Fox gearbox is pretty tough, the only real problem when going for more power is the standard hexagonal drive shafts. They will wear of not properly maintained. These I do recommend swapping for Nova Fox, Thorp or Hot Trick dogbone units if you can find them. If you use the stock hegagonal ones, the boots must be in good condition and you should pack them with a hefty blob of molybdenum grease.

- James

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We run the nova fox at Boondal here in Brisbane.

We also have the original Fox's running around. The Nova is a better performer as the steering mods Tamiya did really helps and the dog bone set up is super free. If it's a runner use the new steering location on the re re chassis. There is no friction or play either as there is no long steering boss or rubber seal.

We all run the Tamiya Torque Tune motor with the biggest pinion. Standard Tamiya kit esc is used too. This combo is perfect for close fun running without being too slow on Li po's. FM ( Fox Man who has over 50 fox's ) has run a 5.5 brushles for insane speed runs on a original gearbox with no real mods at all and never had a issue. If you need to rebuild your gearbox make sure the rubber cv boots are nice and soft not hard as this is causes binding. A trick that we all did before the Nova came out is place

re re Frog boots on the shafts but to do this correctly you need to split the half shafts of their spline. FM built up a jig to do this . It really frees up the drive train

Better still come and see us at Boondal. We are running this Sat with our Fox's. Super Shots, Frog's & etc. We all run Li po's and cheap but realiable electronics. We all run Fly Sky systems for our radio and rx's are $7 a pop.

http://www.ebay.com.au/itm/FS-GT3B-2-4G-3CH-Radio-Model-Remote-Control-Transmitter-Receiver-With-LED-Screen-/161139884537?pt=AU_Toys_Hobbies_Radio_Controlled_Vehicles&hash=item2584af81f9

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Thanks I will head out and take a look. Was hooked on the Fox since the early days and running the hire Fox's at Leasuretronics Woodridge. Funny thing is a guy I know was a part owner in that franchise and states they actually ran the mabuchi 380 and a small pinion to reduce the carnage (apparently) when I stretch them mind back, its plausible given the indoor track and tight turns.

Ironically I've already spent more than the Nova fox kit already and still need a radio, battery, charger, motor and esc but badword I can at least say I owned one. My misses thinks I've left my mental faculty.

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Thanks for the heads up James. I'll use the new holes with the new servo saver set-up and save a bit of lateral load on the steering servo.

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Well I've taken a punt and ordered the business end of the parts.

http://www.speedpassion.net/au/productDetails.asp?p=SP001160&c=CMB

http://www.ebay.com.au/itm/RC-Transmitter-Flysky-FS-GT3C-3CH-2-4GHz-LCD-GT3B-Receiver-for-RC-Boat-Car-/271431865166?pt=AU_Toys_Hobbies_Radio_Controlled_Vehicles&hash=item3f3299934e&_uhb=1

Any thoughts. I'll drop back to an 18 or possibly 19t pinion for better motor gearing compatibility. 18 gives me 7.25 and 19 about 6.87 which is as close as ill get to ideal. Will also run with 2S 5000mah lipos.

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The brushless set up is a good start point - the ESC is sensored and sensorless, so if in the future you want to run adifferent motor you have the option to go sensored. I have that set-up ina Durando DEX210 and it's ample for fun running. I also have a pair in a modified Clod Buster but yet to actually run that !

I've had no issues with any of the SP units i've bought. Be aware the standard ESC software is forward only - you have to download the software from speedpassions website to reprogramme the ESC with different profiles/firmware (ignore the names, you need the crawler one to get reverse from recollection).Other programming (brajes, punch, lipo cut off etc is easily programmed via the software or programme box. Not sure why SP couldn't add an extra field for reverse on/off - would make life easier.

You can't go wrong with the radio system either - with RXs at $6 a pop its a winner with the wallet and gives more facilites than most users want to be bothered with.

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Thanks for the reverse tip, I'd had gone nuts trying to find reverse settings! Any idea how critical final ratio is for these units. Back in the day I'd run any pinion with any motor/esc combo and never had a drama. I've been advised gearing of 5.2 to 6.2 and no longer running than 5 minutes. Seems a little on the weak side if I can only run 5 mins at a time.

"This 3500KV sensorless motor is a standard 540 size motor. The shaft is 3.17mm. The motor rating is close to a 10.5R motor. Recommend Gearing is 5.2 to 6.2 for running no longer than 5 mins.

If you are thinking to install this motor to the Tamiya Fox. To prevent possible of overheating the ESC and Motor. Correct gearing is very important. Please go through the user manual and the recommend gearing ratio chart that provided in the box"

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Can't comment specifically on the Fox ratios but i'm running ca 9.05 FDR on the Durango which is a bit off the Duango recommendation of 8 for a 10.5T motor. Ideally i need to move up to a 28tooth pinion from 25tooth but its giving good acceleration at present, and thats more important to me than outright top speed. A battery battery pack lasts longer than 25 minutes and to date no heat issues

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