BEAVIS

SUSPENSION BUSHES

The second part of todays fun is an upgrade to my suspension bushes.
The existing bushes had spent their entire life over the last 6yrs (or more) in 2 separate track cars, AND I was suffering from a failed bush in a front upper control arm, so things were due for replacement/upgrade.

I opted for the SadFab delrin bush kit (with poly+bronze sleeves in certain locations to ensure suspension doesn’t bind). I was happy to justify the slight premium cost of this over something like one of the off the shelf poly kits as this SadFab kit had all the right answers to maintain free suspension movement and avoid the binding issues of typical poly bushes.

Naturally, this is a fairly extensive job. Obviously including the removal of all the suspension arms, so it took me a good couple of days over a weekend. I am lucky in that I’ve had the suspension apart before, and I live in an area where corrosion isn’t a huge concern, so all of my cars undercarriage comes apart quite nicely.

Bush removal and installation is more or less as per any bushing replacement. Although the delrin bush needs to be reamed after install into the arm as it may deform slightly and this reaming ensures that the supplied sleeve fits perfectly with just the right amount of freedom of movement. Also, because the MX-5 has cam adjustment bolts for the lower suspension arms, this means that the bushes may not always be perfectly square, as such there are certain locations that require a poly bush (rather than 100% delrin). To alleviate the negatives of poly, the kit includes a kind of “double sleeve” (a sleeve with a bronze insert) for the poly bushes to maintain the free movement and avoid the dreaded binding issues. Installation of the poly is much the same, but without the reaming step.

If you are curious on the "proposed benefits" of this kit, I suggest a read of the Bushing Mega thread on the MiataTurbo forum, here: https://www.miataturbo.net/
In terms of performance, I took the car out on track at Winton after these bushes were installed. There was no perceivable change to the ride quality, a mildy sharper and more distinct feel to the suspension, but not a night and day change that I can detect.

I think for the price/performance of the delrin solution, it's not the kit of choice for an every day street car, and really it's targeting the track oriented/enthusiast MX-5er more than anything.






Thanks for reading!

BEAVIS

I'd hoped I would get a chance to take the Turbo NB MX-5 to Phillip Island before year end, thankfully I just got an entry into the December event with the Alfa club.
It was a slightly frustrating day with a LOT of slower traffic on track with me which made it hard to get a comfortable lap, but I ended up with a PB of 1:41.9
I discovered that the car suffers from some fuel surge under the very long left hand corners of 2 & 12, so I needed to keep the tank over half full to alleviate that.
Sadly my GPS wasn't working properly so the data and laptimer isn't perfect in the video, but the official track-supplied timer verified the time.
As usual, some light homework to do and things to tweak before the next event.

And excitingly, now the fastest an MX-5 has ever been around PI.

Video of the day:

You Tube

Midtenn

iTrader: (15)

Surge tank all the high grip Miatas!

BEAVIS

I'm crossing my fingers that keeping the tank above half will sort me out for now. Surge tanks add cost and complexity that I'm not ready for.

A few images from Phillip Island 2 weeks ago thanks to a fellow MX-5er.