Vorshlag Tester Jerrett Jan's STS2 Miata (NA chassis)

[Fair!]

Wanted to go ahead and start this thread for JJ's Miata. He has been running the car in EStock locally for the past few years and was ready for the move up to STS2. We are working with him via our Test Program to help develop 4100 shocks for the NA/NB chassis. AST has made many sets of coilovers for these cars in the past but we here at Vorshlag have not sold them in 4100 form yet (only 4300s). Here are a few pictures of the shocks then we'll move on to the install, initial test impressions, and setup discussion.


L: Long shocks are the fronts, short are the rears. Knob is for rebound adjustment
R: Lower bushings are spherical. Upper is made to work with the stock NA/NB upper mounts


This was one of the ride height iterations, which was eventually lowered more at the rear.


Left: OEM front is 14" long and 150#/in, rear spring is 11" and 90#/in (SOFT!). We are using 7" 60mm ID Hypercos, 550 #/in front, 350#/in rear

The dyno plots of these things were beautiful. We're going to dyno the Konis that were on here before and compare. We dyno'd some Koni doubles last week that had some pretty interesting results (like "non-working adjustment knobs").


click to enlarge

Above left you can see the AST 4100 Miata rear shock being tested on our Roehrig 2VS shock dyno. Middle, you can see Hanchey making a CVP plot. Notice the large force changes over the range of rebound adjustments - this valving package can deal with a nice spread of spring rates. Right, new dyno fixtures had to be built for the lower eye mount (1.800" width) but our standard upper stem mount fixture was used for the upper mount - this was made with a VoMo camber plate, of course!

http://vorshlag.smugmug.com/gallery/6717983_45S6v = Miata 4100 Install Gallery