- Tamiya TRF417 - BDCK - Very High Grip Carpet Track - 05.03.2011 -

I'm mechanic on a 417 for my son, and last week we were practicing on a very high grip carpet track - lay out very fast and open, but with some tight coners too.

At first we ran our normal setup using 2x E blocks in front and no spacers at the front wheels. At the rear standard setup XA in front and E block back. Droop was 6 mm front and 5 mm rear. 0,5 mm spacers all way round under the suspension mounts. Upper link mount was 3 mm both front and rear. At the rear uprights we had 4,5 mm spacers. Camber front 0,75 degr. rear 1 degr. Standard roll bars both front and rear. White Tamiya springs in front and blue in the rear. 450 cst oil in all suspensions.

With this setup we had some problems, that the car hooked into corners and tendend to make grip rolls. The rear was stable as usual.

For the first we changed the the droop to 7 mm in front and 6 in the rear. It helps a lot. Weight transfer as someone mentioned. Then we changed the front blocks to D+D and raised the roll center using 1 mm spacers all around under the suspension mounts. We used 0,5 mm spacers at the front wheels. Upper link mount now 4 mm in the front and 3 mm in the rear. At the rear we changed to HPI blue springs and changed to the inner hole on the lower suspension arm. Rear upright spacers changed to 3,5 mm. Camber now 1,5 mm front and rear. Still using 450 cst oil. We also lowered the car in the front to 4,5 mm and 5 mm in the rear. Still we use a PF Mazdaspeed body.


The car was very quick after the changes and had only grip roll, if he made some drastically quick steering adjustments in the high speed corners. The car was also very easy to drive.

This weekend we have a race on the track, and I think, the grip will go even higher. I will remenber some of the tricks you have mentioned here.

If I found some new tricks, I'll let you know how they works.


PS: we also run the servo link in a special way. We don't use the normal hole in the steering brace between the arms. We use a longer link from the servo and connect the link to the right arm (seen from the back). Changed the screw in the arm to a ballscrew. By using a longer servo link, the steering is not so sensibel as with the normal short link, when connected to the brace between the arms. I hope, you know what I'm trying to tell you.

Source:

RC Tech