@TRF_AK:
Spares:
- Front suspension arms (F-Parts)
- Front suspension block (J-Parts)
- Front shock tower (M-Parts)
- Front nose piece (L-Parts)
- Some screws (Hardened steel stuff, not alu, titanium or any other type of stuff), spacers (for the roll center adjustment) and nuts (wheel nuts and stuff).
Hopups:
- Ceramic Diff balls.
- Ceramic Diff thrust bearing balls.
- Reinforced Differential Gear set (black gears instead of the white ones - on the white ones some drivers had teeth break out under normal use).
- RudeBits Under-servo weight (72g).
- XA Suspension Hanger (+0.5 degree toe-in).
- Front axles for Imperial bearings (always handy, you might end up borrowing a set of front wheels/tires from someone, for example to try a tire you don't have yet).
- Associated 75T Spur gear (if bite is high you can move the motor to the front).
-
Trackstar +6mm tub. I expect the XR conversion is quite expensive (at least the MSRP is ridiculous), and you might be able to discuss with Trackstar a custom wheelbase increase. A longer wheelbase is the only hopup I mention here that I haven't tested, but from everyone I hear in general about +...mm conversions, you just can get away with more before your car becomes unstable and bites back... so it should be worth the money.
- Associated F+R spring sets. Cheap and cheerful and a good starting point being that the spring set was developed together with the B4... and let's face it, they are quite similar in the majority of the construction.
Mods/Tips:
- Tape or glue the cap of the spur gear cover, it tends to come off and get lost in crashes/knocks in-battle (I had it >5 times in one season).
- Tape the spur gear cover shut on top of the motor plate to make sure it's properly sealed. There is a hopup motor plate with an embossed edge, but I found it still doesn't keep out the dirt, ending up with a worn spur gear and pinion after only a few meetings.
- Add 2mm spacers between steering arm/knuckle and the ball connector of the tie-rod to reduce bump-steer.
- Immediately get rid of the blue alu ball connectors. Instead, replace them with fluorine coated low profile ones (you do need the low profile ones for proper clearance without mods).
- You could get the XV-01 Reinforced rear uprights/E-parts to make bigger clearance between the rear springs and turnbuckles - it also allows finer tuning options for the rear roll center.
- If you buy the J-parts, you have a spare T-plate. These don't break, so I suggest you try out this
T-Plate Mod.
- If you want to use an under-LiPo weight, make sure you use the plastic battery plate. The construction isn't really made to accept LiPos anything higher than 25mm, so it's nice to have a battery plate that can bend/flex over the battery. If you do so it may also be worthwhile using longer grub screws on which the thumb screws fit.
- Use a shorty pack and some foam spacers: it's a nice piece of weight balance adjustment, and the car felt better with one imo.
- Avoid alu mods where you can: The Tamiya plastics are pretty tough in general and I've not broken stuff like plastic rear hubs or suspension hangers... and actually, I found the alu to wear down more quickly in stuff like ball joints than the plastic parts did.