Suspension Updates 1/4/18

Over the winter, I wanted to make some suspension updates.

Front Lower Arms

I bought these front lower arms a couple of years ago from someone on the V8 Miata board.  I had already installed my stock

Billit lower arms.

arms, so I put these on the shelf.   Now was a good time to install them.   They fit really well, and are lighter than the stock arms.   It would be really easy to adjust them for some pretty radical camber.

Springs

Bump Stops, even after cutting them in half.

It was clear that the spring rates were not high enough.   The bump stop were jammed up into the top of the shock hats.  I tried raising the ride height up more than I really wanted it, and cutting the bump stop in half.  But I was still down on the bump stops.   When that happens, you’r not really using the suspension any more, and it all becomes solid.

So, I went to a higher rate all around.  I added 50# to each corner.

Ride Height

There’s been a lot of talk about ride height on the Facebook page.  Finally, some Miata experts have been taking a close look at the Exocet, and making some recommendations.

I set the front at 5.5″.  Because of how the rear subframe mounts in the Exocet frame, it was recommended that the rear be a little bit lower.  That actually sets the Miata subframes pretty square.  I set the rear ride height at 5.25″

Alignment

After installing the new bushings, I needed to do a new alignment.   I used a lot of the data I gathered from the last two seasons to set the new alignment specs.   You need to keep in mind that there is very little body roll in the Exocet.  You don’t need a lot camber, front or rear.   2 years ago, I started out with the recommended race settings for a Miata.  Based on tire temps, and gradually decreased those radical camber settings.  As I did that, the tire temps looked better and better, and lap times got faster and faster.

Front:  Camber -1.25*  Caster 5*, Toe out 1/32″   Rear: Camber -1*, Toe in 1/32″

With the new springs and bushings, we’ll see how these settings actually work.

While I was at it, I replaced all the concentric bolts with the updated version, and used the new Paco Motorsports eccentric locks.  Why?  Because it made me feel warm and fuzzy inside.  🙂

Paco Motorsports Eccentric Locks
4 wheel alignment

 

 

 

 

 

Corner Weight

Now that all this is done, the final step is setting corner weight.  There are lots of articles on the web on how to do that, so I won’t go in to a lot of details here.   Essentially, I wanted to adjust the corner weights to get them as even as possible.  The weights are with a full tank of fuel, and me in the drivers seat.

Cross Weight. Full tank of fuel, me in the drivers seat. 12/17.