Frog Transmission & Diff Upgrades...etc

[GriffithBuilt]

Hello,

I'm new here and just dug my old Tamiya Frog out of the box it has been living in for the last 10-15 years as I was contemplating buying a new nitro stadium truck and decided instead to play with the car that I have had for so long.  Of course, I took it out, jumped it about 30 times over a small incline and busted the shock mount on the rear control arm.  So I got it apart and have some new parts on the way and I got to thinking....what could I do to turn this thing into a monster without sacrificing the parts that I have that are the most prone to damage. 

I've got a 15 turn Venom electric motor for this car and I know it will grenade the transmission/diff in no time so I have been contemplating designing a variable ratio (swapping cogs out - preferably from below for quick change) mini-gilmer belt drive gearbox and differential for it, but I'm still trying to figure out what parts of the transmission are the most prone to failure with copious amounts of extra power. 

And in the meantime I'm seeing what I can do about designing a new adjustable front damper system that will allow quick changes of the spring rate and/or ride height of the front end.  I'm far better suited to getting something done on this front in a short period of time so I thought I would begin there, and move to the drivetrain (as my current motor & trans/diff is in very good shape).

Any thoughts?  With moderate to radical modification a possibility, what differentials can I look into for a decent fit to a dog bone style IRS?  I do have access to some high end cnc machines including a wire edm, cnc mill & a manual lathe.

Thanks,

Jason

[DJTheo]

The re-released Frog uses dogbones, you coud use those parts although the other problem of Frog tranny which is bending gearbox plates and causing diff slip seems unsolved, another option would the King Blackfoot rear end. In the end a ST made from a Frog will cost more then a modern used ST and it will never be as good but if you enjoy buidling and experimenting why not?

Cheers

[TAZ-NZ]

Start with oldfrogshot's drive cup screw mod, links below.

http://www.tamiyaclub.com/showroom_model.a...74&sid=3142

http://www.tamiyaclub.com/xforum/topic.asp?TOPIC_ID=8104

It work great, I got a full set of the custom axles and modified TA04 cups with the screw mod & set of dog bones from oldfrogshot, and installed them on my Mudblaster. It's running a Kyosho Magnetc Mayhem 22x1 turn 550 motor, running off a 8.4v battery, so a lot of stress is being put of the drive train, and I'm yet to have an issue with this setup.

I've got a full set of the new re-release Frog dog bones & axles coming, and I plan to do the screw mod of the drive cups and them mount them in the Blackfoot I'm restoring.

You should also of course ball race the whole transmission and axle assembly.

Also see if you can hunt down a set of CRP Diff. Bearing Supports (1608)

http://www.rcchopshop.com/images/crp/crp1608b.JPG

And a CRP Adjustable motor mounting kit (2107)

http://www.rcchopshop.com/images/crp/crp2107.jpg

Both can be found of ebay from time to time.

Make sure your transmission side plates a dead flat, if not dump them and get another set off ebay cheap. Also as long as you have your spur gear is ball raced, glue the B1 parts to the transmission side plates to stop them spinning and wearing out, and creating play in the transmission, if they are worn dump them too.

You may also want to get a set of Thorp aluminum wheel hubs or look into getting some aluminum hexs and set of after market wheels.

I've also thought of looking into the possibility of  making a belt driven ball-bearing diff transmission, using the parts from a TLT-1 transmission, but I've never had all the parts in front of me at the same to work it out.

Hope some of this helps.

TAZ-NZ

 

 

 

 

[DJTheo]

Now also original Tamiya hop ups for it! [][H]

http://tamiyaclub.com/CS/forums/ShowThread...D=159728#159728

Cheers