XRAY - Model racing cars

When using 28mm wide foam tires, most drivers like to shave off the lower outside shock mounting block on the rear arm to allow the lower shock mount to clear the foam tire rim while making use of the outside mounting position. After running this setup, there are some issues with this method.

1. As the rear suspension compresses, the inside of the rim will rub on the lower shock ball joint (308310), eventually causing it to fracture and pop off the ball universal (303240). When one of your shocks breaks free, needless to say, the car is uncontrollable - this is what prompted me to suggest this option part.

2. In mounting the lower shock this way, it also forces an exaggerated mounting angle of the shock towards the front of the car. Often you need to add spacers at the shock tower to allow the shock to pivot freely as it should.

3. To race foam tires, which is becoming more a standard at ROAR events, one shouldn't be required to dremel of a large portion off the rear arm for tires to work properly. Not to mention that if you break an arm, it requires considerable time to create the modified part.

Now, here's the problem...

If you simply move the lower shock mount to the inside position, all is well. The lower shock mount clears the 28mm tire perfectly. One can still attain the same shock incline as there are plenty of upper mounting holes available - in essence the same damping can be created.

However, even if you move the shock spring collar all the way up as far as it will go, it's almost impossible to get a ride height lower than 5.5mm - this is too high for carpet racing. Either the springs are too long or the shock tower too low - either way you have trouble getting the proper ride height.

The good news is that I think it's a simple fix...

Create a " rear foam shock tower" designed for smaller diameter and wider (28-30mm) foam tires that would move the upper shock mounting holes higher in effect allowing you a lower, proper ride height in the 4-5mm range.

This way, when you want to run foam tires, move the lower shock mount to the innermost hole and maybe the upper mount in also to maintain the same damping angle. You wouldn't have to dremel anything on the rear arm and the tires would never rub on the lower mount when the suspension compresses.

Make a companion part to the front foam shock tower - it's that simple!

Hey sounds good to me........