TA03R - RWD with 4WD brakes

[LeftyAl 164]

My interest in a RWD car with decent brakes was piqued in a thread a little while ago. After the talk about one way bearings it got me thinking about trying this out on my TA03R.

It started life out as a TA03F my mate bought nearly 20 years ago. I spend an afternoon at his house helping him built it. About 5 yrs ago he was cleaning up his study and dropped it off to me in near mint condition as it was just taking up space and not being used. Seeing as I already had a heavily modified TA03F I decided to turn this one into a TA03R. It was used a couple more times and then hung up on the wall.

Now it has been bought back to life with the purchase of a Torque Splitter part # 53279. I opened up the front gearbox and installed the unit with the bearing reversed. Just gave it a quick test run and it has all the characteristics of RWD lacking traction, but with 4WD brakes. It has gear diffs so the rear end steps out quite easily with a Tamiya 23T motor.  

Next steps are to strip the gear boxes down for a re oil/grease and put in a 3000kV motor. I have a good supply of new tyres so will also spend some time seeing what works well. Will also try putting the torque unit in the rear gearbox to see if that makes any noticeable difference.

Whilst this isn't necessarily the most exciting, original or ground breaking news, anything that helps keep an interest in a neglected chassis must be a good thing. 

[ThunderDragonCy 7886]

Great stuff. Following with interest to see how you get on with setup and tyres. 

[LeftyAl 164]

Pulled the gear boxes last night. Greased the gears and oiled all the bearings. Bolted in an 11.5T motor with the stock 14T pinion. As expected lots of over steer both on throttle and off throttle turning. But it brakes in a straight line. 

Next step is to try some foam GRP tyres and then some soft rubber tyres. After that I will try the one way on the rear counter shaft.

 

 

[LeftyAl 164]

Spent some time trying to sort the steering out. In the last drive no matter how much I trimmed the steering the car would pull right. Found the culprit to be a hit on the front right wheel had managed to damage the rear gearbox where the hinge pin goes for the lower arm. Found an old one, cleaned it up and installed it. Will drill out the old one and install a flanged tube to repair it so I will still have a spare.

Reset all the steering back to factory measurements and checked the servo for centre.

The Colt slicks I used last run are pretty hard. Good for donuts and sliding, but not much chop for decent control (probably helps to explain to hit on the front right). Put a set of Tamiya Narrows on for the next run.

Will be going down to the local netball courts on the weekend, so if i have managed to sort the steering and handling.... I will install a bigger pinion and see what sort of speed it can make.

[qatmix 794]

The TA03 is a good choice to try to make rwd. The stock car has 2deg caster and that’s a good start for rwd. 

 

You up want to up the rear toe in as high as you can go. Then look at your springs. The R version has the motor in a good place as well for stability. 

 

I personally wouldn’t go all in with a 11.5t motor until you have the car dialled with a slower motor. Most 4wd cars will oversteer if you chuck loads of power at them.

 

looking forward to seeing how you progress.

[Juls1 1661]

I did the same thing with a MF01X chassis and a Porsche RSR shell, all the spacers, TL01 driveshaft and suspension arms to complete conversion. Coincidently you use a TA03 front one way diff in it but installed backwards to get 4 wheel brakes but only RWD, of course the MF01X is rear motor so it suited my Porsche application. 

Juls

[LeftyAl 164]

Rain over the last few days has stopped any more testing. I found a yellow (soft I think) swaybar and bolted that to the front.

I'll also dial the punch down a  bit on the ESC.

[LeftyAl 164]

We got a sunny spell that dried up the ground enough to do some more testing this afternoon. The Tamiya soft narrows made a huge difference. Much more controllable and even managed to do a  few traction rolls. 

It does donuts better in reverse now . Through the week I will move the one way to the rear countershaft and see how that goes,

As I mentioned earlier, whilst the exercise is not ground breaking it is certainly entertaining enough. Thar car probably hung on the wall for the best part of 3 yrs since it was last enjoyed, The FF01 thread got me thinking about getting my FF01 off the wall....then remembered how much the new gear case was that I installed after the last run.... Might have to get an FF03.

[LeftyAl 164]

I worked out today that dampers will work much better with some oil in them!!!! That will help dial out some of the erratic changes of direction.