I try to share here my experience with the Astute.
Astute is a beautiful and fast car on the track but is too fragile to have a pleasant driving experience without some modification. Driving the Astute as Tamiya reference will be really frustrating due the frequent and numerous failure and breakages. I fronted this problem and made an experience to avoid the failures so will try to share them with you Astute fans.
1) Front end failure. This is the easiest and common failure. You can avoid it adding a Super Astute part, the G4 brace, to your Astute. This is a MUST have part to drive the car for more than 3 or 4 minutes (Pict 01).
02) Another solution is the Madcap front bulkhead that is a little bit stronger than Astute one. You can run it without a brace but is a lottery, you can win or you can fail. With Astute bulkhead without the brace you can only fail.
Anyway there's a brace also for the Madcap bulkhead but it's tricky to use. In fact it is designed for plastic bathtub chassis. You can mount it with a FRP plate chassis but you need a couple of aluminum columns as I did on my Madcap (picts 02, 03 and 04). You must drill two more holes on the FRP chassis to accommodate these two new columns. These new columns must be 25 mm height.
The Madcap bulkhead is not identical to Astute one. The Madcap is longer on front to accommodate larger bumper but this doesn't prevent the use of Astute smaller bumper. The other difference is the front arms offset that is more back in the Madcap. This can give some minor problems if you use dampers with bushings, no problems if you use dampers with ball connectors like Hi Cap Dampers (pict 5). Obviously the car will be some mm shorter if you use Astute uprights. To keep the same wheelbase you must use Madcap or Super Astute uprights with Madcap bulkhead. Madcap bulkhead is also lighter and doesn't need the 730 bushings or 730 ball bearings.
3) Front arms: another modification for the Astute is the front arm swap with Madcap ones. Astute and Madcap front arms are almost identical in width and length. The only good reason to swap them is the lack of Astute spares. There are only few differences between the two arms. Damper position is different. Both arms have 3 damper holes but on Madcap they are more inner so Madcap middle hole is Astute inner hole. Another difference is the offset. On the Madcap arms the damper mount is more ahead in front of Astute one to compensate the different arm offset on the bulkhead. The result is that if you mount a Madcap front arm on the Astute bulkhead the dampers will be more inclined ahead in the lower mount and the wheelbase will remain identical. If you mount a Madcap arm on the Madcap bulkhead the dampers will be not inclined but you must use the Madcap Upright also or the wheelbase will be shorter. In fact Astute Uprights have the wheel axle some millimeter back to compensate the different C-Hub offset in the Astute and keep the same wheelbase.
Super Astute arms is another thing. Astute upright have the wheel axle back like the shopping carts. This allows to keep the straight direction of the car. After the release of the Astute Tamiya made the Madcap with different bulkhead, front arms and uprights. In the Madcap the traditional Hornet uprights have the wheel axle in the same position of the steering axle. The wheelbase is equal to Astute but the geometries of front upright are different. With the Super Astute Tamiya decided to keep the Astute bulkhead and the Madcap wheel base together. A new design is for Super Astute arms, with the correct offset for the dampers and more inner holes to increase wheel travel and car height. But the SA arm curves back to obtain the same wheelbase than the Madcap. This allows to use normal uprights without wheel axle back.
In my opinion the best choice for the Astute is the Super Astute arms that are stronger and keep the normal uprights. Madcap arms are lighter than Astute ones but are softer and flex a lot so there's no vantage to mount them.
4) Front uprights and C-Hubs. As you can see in the pictures Astute front C-Hubs are crazy complicated and heavy with a total of twelve 730 ball bearings (or bushings). Madcap C-Hubs are the right solution but keep in mind that Astute upright have a different wheel offset. This is compensated by the different bulkhead in the Madcap or the different shape in the Super Astute arms if you want to maintain the same wheel base. The best solution in my opinion is Super Astute front arms and bulkhead with front brace, Madcap C-Hubs and Super Astute/Dyna Storm uprights.
Madcap C-Hubs are lighter, simpler and allow a normal upper arm with 5 mm ball connector.
Super Astute upright have the same wheel offset than Madcap but a longer arm that allows a more precise responding in the drive.
G4 part from Super Astute a MUST have.
Stronger Madcap front bulkhead but not enougth.
Madcap front brace. Needs a plastic chassis or...
Aluminum columns to adapt the brace to FRP plate.
Differences between bulkheads.
Differences between front arms.
Correct position of the arm on each own bulkhead.
Too heavy and complicated with cart style uprights
More simple but needs Madcap bulkhead and upright.
Different axle offset for the same wheelbase.
5) If you want to fit Super Astute steering arms on Madcap C-Hubs you must file the white part of the arms. Original Madcap Steering arms are 11 millimeters height, Super Astute are 13 millimeters so no direct fit. A little bit of work is needed to bring the Super Astute pieces to 11 mm.
P.S. Sorry for my bad English. If you see some error please write me in PM and I will correct it.
If you liked those pictures, you should see these...
Astute: a guide based on my experience part 02