Help with suspension problems?

[mxfive]

Hi All,

I have a red 1993 NA LE with stock suspension.

I took the car for its first long drive (well Brisbane to Toowomba, not very long but long enough) since I got it.

Car performs like a ripper except the suspension is absolute crap, every little bump in the road I just about get shot straight up and if it wasnt for the seatbelt holding me in I would have a great ejection seat system and I am not exactly a small build (well lets face it I am fat). I also have to hold on tight to the steering and correct it on every bump to keep it going straight. And then there is the almighty shudder throughout the entire car when you hit even a minor pothole or bump, its teeth grinding stuff.

So I did some research on the forums and everyone was going on about how good Tein Super Street pro kit was so I thought I would go with that and see if that fixes it.

So I took it to Fulcrum the other day and they spent an hour checking it out only to tell me it is all fine, apparently thats just how a NA handles. I am not doing racing with it so they dont recommend I get the Tein Kit as it will only make the car worse apparently but they did suggest I get bracing for the car. Just waiting on their quote.

So now I am confused, what do people recommend I do about this problem?

Any suggestions would be greatly appreciated.

Regards,

Grant

[JBT]

Get the bracing - maybe even think about buying the roll bar made by MX-5 Plus for protection and bracing.

Check your tyre pressures (they may be set to some silly cold pressure like 35-40psi). Try setting about 30 psi cold and see if that helps.

[Okibi]

Suspension and bushes might be getting close to their used by date.

[mxfive]

Thanks for that.

I already have the MX5 Plus roll bar its the twin hoop model, very happy with this purchase.

Fulcrum said the original suspension and bushes were all fine and didnt need to be replaced but they didnt do a test drive in it especially on a bumpy road.

It drives fine on smooth city roads but I have a bump at the end of Webster road at Aspley near where I live that sends me out of my seat everytime no matter how slowly I take it.

I will try changing the tire pressure and see if that helps.

For Xmas I am purchasing a new set of Michellin PP2's and a set of 16" rims instead of the 14" ones I have now that dont fill the wheel well to see if that improves the ride.

[JBT]

16" wheels will only make it worse because you'll have to use very low profile tyres to keep the rolling diameter the same. My recommendation is to not go any bigger than 15" on an NA - and then use NB wheels to keep the weight similar.

Fulcrum have a machine that shakes the car around whilst a suspension specialist visually checks what's going on with the suspension. They'd certainly try to sell you new stuff if they thought your suspension was poor.

[tbro]

mxfive,
Come for a drive to Narangba and I'll have a gander for you, then you can take my Clubby for a run and feel how a properly sorted NA should ride.
PM me for phone no and address.

Terry

[bensale]

Maybe it could be good to go for a ride in another standard Mx5 to see how it compares?

Are the shocks and springs all standard (they should both be black)

Another thing to consider is how much does the car sag when you're in it. The na has quite limited travel in the rear suspension and if the car is sitting low with you in it what you are feeling is quite likely the suspension hitting the bump stops. As my car is lower it has a set of fat cat motorsport bump stops fitted which are both shorter and progressive which means it takes more to bit them and when you do the ride is a lot less harsh as they compress rather than acting as a harsh stop straight away.

[mxfive]

Maybe it could be good to go for a ride in another standard Mx5 to see how it compares?

Are the shocks and springs all standard (they should both be black)

Another thing to consider is how much does the car sag when you're in it. The na has quite limited travel in the rear suspension and if the car is sitting low with you in it what you are feeling is quite likely the suspension hitting the bump stops. As my car is lower it has a set of fat cat motorsport bump stops fitted which are both shorter and progressive which means it takes more to bit them and when you do the ride is a lot less harsh as they compress rather than acting as a harsh stop straight away.

Here is a picture of the back wheels when I am not in it, see how far up the car is sitting at the back.



Here is a picture side on:



Don't have a picture with me in it so I couldnt say how much sag there is I did say earlier I am fat so it should be a bit.
As far as I know everything is stock 1993 vintage.
This is my first MX5 so I have never dríven in another one to compare it against. Tbro has kindly offered so I will take him up on this.
Its not hitting the bump stops as far as I can tell just the opposite the springs are so good they are sending me out of the seat instead. You can really feel the springs when you lean on the back of the car. I was even sprung off them one day that I tried that. Its either the springs doing that or the car took offence to me sitting on it like that.

[bensale]

To be honest that doesn't sound right to me. My car never sprung back like that on stock suspension. Also I'm sure that if they did that when new to the extent of throwing you out of the seat it would have been reported by journo's or owners.

Also that seems to be sitting way too high at the back. Are you certain everything is stock standard (a quick check to see if the springs and shock are black will answer that (after market is normally coloured). Although with that guard gap you would probably be able to see it in the photo if they were coloured.

As far as I understand the spring bouncing back from compression has a lot to do with the rebound dampening of the shock. To me it sounds as if there is far too much rebound for the rate of the spring...

If you do hit the the bump stops it will bounce back quite violently to the point that it will upset the balance of the car quite a lot (its not a nice feeling). The symptons still sound to me like you are hitting the bump stops but if it bounces back in the same way when you compress it with your body it's probably not the bump stops then as for it to bounce the way you describe there would have to be a bit of force involved.

Tbro's clubman is from the sound of it really well set up, having quite a nicely modified after market set up (the thread on it is quite interesting) so it wouldn't really be a fair back to back comparo. However, it would be a good way to see what is capable. Maybe you could take anouther car (ie not the mx5) down to a dealer with a na6 for sale and take it for a drive on the proviso that you're looking to buy one.

PS: The car looks great, really clean! The red and tan is a nice classic combo

[JBT]

It does look a bit high at the rear. Something ain't quite right.

[mxfive]

It does look a bit high at the rear. Something ain't quite right.

Thats what I thought but Fulcrum gave it a clean bill of health which is why I am confused as to why it gives such a poor ride on only slightly rough roads.

The road to Toowomba is not all that rough either compared to some country roads I have dríven. I wouldnt really call it a country road either as it is all bitumen unlike some I have been on i.e Between Brisbane and Cunnamulla.

It isnt even as rough as some of the concrete roads you get in New South Wales like the one near Lismore.

So if it cant handle the Toowomba road well I would hate to take it out on those.

[JBT]

It looks about right at the front. I wonder if a previous owner changed the rear springs or shocks and put the wrong ones in.

[93_Clubman]

The '93 NA6 had extra bracing over the earlier NA6, which is not to say it couldn't use more, but already having the twin hoop Torque Box rollbar will also certainly help. As the others have said something's NQR, & it does look a little higher at the rear in terms of the gap between top of the tyre & bottom of the guard when compared to standard.

[Juffa]

I have to agree that the rear ride height does look higher than normal. If you have the cars history see if there was any indication of suspension work.

Re the wheels. You have the factory fitted BBS wheels. They don't get much lighter/rarer than those on an MX-5. Get youself some decent tyres, the right air pressure and a good wheel alignment....it will do wonders for the handling, and may go some way to addressing the issue as reported.

J

[mxfive]

Took the car over to Richard Larson at MX5 Plus today and he diagnosed it as being the shock absorbers as the car has about 160,000 km on it now and these original shock absorbers have gotten too loose. He showed me what a good set should do and mine are no where near as good.

So I am still thinking of getting the Tein Super Street Pro setup after reading a write up about them in the MX5 club newsletter.

Is anyone here able to share their personal experience of these or make other recommendations on shock absorbers?