Building a NASA NP01 Prototype the Right Way with Stoptech! Part 2


Like the front shocks the rear MCS shocks are a monotube double adjustable design. The shocks are adjustable in compression and rebound.
Although the rear suspension is very much like the front, there is no antisway bar in the rear.

The rear suspension has control arms that are adjustable in profile by the use of different mounting points on the transaxle case, meaning that the antisquat, roll center and camber curve in the suspension geometry can be adjusted.  This is typical of a purpose-built racecar. The standard setting from Elan is 20%.

The control arms are long and the inner pivots are not that offset meaning both the front and rear suspensions have gentle camber curves compared to a production car at .5 degree of camber gain per inch of bump.  For a car with limited body roll like a purpose built race car this is a common design practice.


The rear brakes use the same Stoptech AeroRotor as the front brakes.  This helps reduce the number of spares a club racer must own. The hubs used are the same on all 4 wheels and are a common GM part that is both cheap and strong. This is another example of reducing the amount of spares needed.
The rear StopTech calipers are the same as the front with the exception of having a leading or trailing fluid crossover tube which can be switched around for quick track repairs. All bias control is in the master cylinder sizing and the balance bar.

The rear calipers are mounted towards the front of the car so they can get more cooling air flow and for a lower polar moment of inertia. The calipers are plumbed to the dual master cylinders with Teflon lined braided steel hoses. One master cylinder is for the front brakes and the other is for the rear.

The brake pedal is moved back and forth between the two master cylinders on a threaded balance bar that has the push rods for both master cylinders on either end.  The position of the brake pedal on the balance bar controls the mechanical brake bias as it affects the amount of leverage the brake pedal has on either master cylinder.


The StopTech NP01 is starting to look like a racecar now!

The Stoptech NP01 is nearing completion and we will be starting to do the final touches on the chassis and fitting the body next.  Stay tuned for the completion of the affordable Prototype and in the meantime be sure to catch up on the first part of our NP01 build and our test drive analysis.

Building the NASA NP01 Prototype – Part 1NASA NP01 Test Drive Analysis

Check out our driving impressions of the NP01 press car.

To read about how the build of our car started check this out!

Part two of putting it all together look at this!

Part Three is here!

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