John Magnuson

I recently purchased a used set of the Advanced Design coilover system that used to be sold by M2 Performance. While I do a lot of track days I also like to drive my car on the street.

After installing the AD coilovers it became apparent that they transfered WAY too much noise into the chassis of the car for me to tolerate on the street. Although the stiff ride was tolerable the constant banging coming from the strut towers, particularly the rear, was not.

I figured one of the main culprits was probably the solid top mounts and tiny Eibach Springs. I really liked the double ajustable from the top feature of the AD shocks so I wanted to find a way to make them work with the stock rubber top mounts.

It turned out that the spring perches that came with my previous Koni shocks fit over the coil adjustable spring perches very well. I purchased some RSR Race Spring which have almost the same spring rate as the small eibach springs that came with the AD coilovers but will fit with the stock mounts. I also went ahead and used the Mazdacompetition top shock mounts (same as stock but a bit harder rubber). Put it all together and you get my hybrid coilover (pic below).

Results?

Street: Much less noise is transfered into the chassis than before. I can tolate this setup on the street but it's still much stiffer than stock.

Track: WOW! The car handles like a completely different animal. Much tighter, faster responses, increased grip. The adjustability is a great feature. Being able to quicky adjust both compression and rebound from the top is great. Just got back from Buttonwillow and my times were significantly improved. Of course everything happens faster including how quickly you lose it when you push it too hard. I found this out all too well on the last lapping session when I went into a turn too hot and spun out into a tire lines embankment. Forturtunately I wasn't going too fast and just got a couple small bruises on the fender. Sigh... sometimes I start to think I'm better driver than I really am and I pay the price (pic attached).

G's 3rd Gen

iTrader: (11)

sound like a nice set-up.. What is approximate cost of your set-up?

1234rotor

iTrader: (1)

Hmmm, so the banging was from the spring being so short( not pre-loaded ) and the lack of some spring seats I guess. I love those shocks, how much do they go for new and used? How much were the parts to hybrid the system?

ptrhahn

iTrader: (9)

Odd, because as far as i know, the upper perch on an AD coilover is a Ground Control part... my GC/M2 coilovers have a rubber mount built in.

John Magnuson

New the shocks are about $400 each from Ground Control, http://www.ground-control.com

A complete kit from Ground Control would run about $2200 which includes 2.5" Eibach Springs (mine are for sale if anyone wants them, 500lb front, 400lb rear) spring perches and top mounts.

What you need to make the system I used:

1) Advance Design Shocks (~$400 each new, ground control)
2) Adjustable threaded spring perches for shocks (not sure of price, ground control)
3) Bottom spring mount from Koni Shocks (not sure it they're available seperately or not from the Koni Shocks)
4) RSR Race Springs (~$200. available from various venders like RX7store)
5) Stock upper spring mount (reuse your own or buy new)
6) Stock upper shock mount (reause your own or buy new. I bought new Mazdacomp ones for about $40 each.)

John Magnuson

Yes, the ground control upper mount does have a piece of rubber between the spring and the top mount. But it doesn't do nearly as good a job of reducing vibration and shock as the stock mount.

Maybe I'm just a big baby but after driving one day with the solid top mount I decided it was not tolerable.

Do you have the GC top mounts with a soft spring or shock? That might make a big difference. The Advance Design system I'm using is 500lb front and 400lb rear.

ptrhahn

iTrader: (9)

Nope, mine are on Koni yellows, with 500 lb front, 400 lb rear springs... and I have 18" wheels. I honestly didn't notice that the vibration or anything was really much different from the eibach pro-kits w/ stock upper mounts that I replaced.

In fact, I thought the ride was better because the higher spring rate kept the car from crashing over undulations and bumps.

John Magnuson

Interesting... might just be that the Advance Design shock damping rate is so severe... hmmm... I'll try cranking the compression and rebound down to the minimum next time I take it out on the street and see what happens.

7Langit

I looked at your "bruised" 7. It is exactly my car in color. It was like looking at my car in pain. Too much for me to take. But, "if you're gonna play you have to pay".
Maybe it was like the good 'ol boy stock car driver said when asked why he crashed. "I just ran outta talent". Or maybe you lost your "gription".

I've decided to go with TEIN Flex coilovers and electronic adjustment on the dash.
I think they'll work for street and a few track outings and maybe a little auto cross.