What could cause a 'buffeting' vibration at 70mph+

Madtoady

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British Zeds
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Rochester, Kent
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Maybe a daft question but have you got a wind deflector fitted??
I do indeed but have had it fitted since I bought the car and not had this issue. Before I changed my wheels and suspension I got up to 115mph (on a private road!) without any issues. I didn't have the confidence to go faster as the tyres I had were cheap and 9 years old.
 

Sean d

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Z3 2.8
The last few weeks my 2.2 has been doing something odd on motorways and dual carriageways. ie at speed, 60+.

It's like a big gust of wind catches it from time to time. Just for a split second But it's always been calm when it happens. The car doesn't wander off and I don't need to adjust the steering.

Iv'e never had handling issues before with any of the Z3s I've driven. In fact if I'm honest I'm still not even sure what tramlining is or if this is what I'm experiencing.

This car has all new front end suspension arms, links, bushes and mounts. Though the struts/shocks were not replaced. Thinking about it, it possibly started happening when I put the 18" wheels on.

Any ideas what it is or what might solve it while we're having a handling discussion?
I used get this in my 2.0l when it was tram lining and even when sorted it still did it, more so on the inside lanes of motorways, I put it down to wear on the road surface from trucks, sometimes you can see the wear lines and know its going to happen but its still very unsettling.
 

mrscalex

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I used get this in my 2.0l when it was tram lining and even when sorted it still did it, more so on the inside lanes of motorways, I put it down to wear on the road surface from trucks, sometimes you can see the wear lines and know its going to happen but its still very unsettling.
Thanks @Sean d So I’m just describing what is good old-fashioned tramlining then? I’ll take a look at the suspension. But timing wise I suspect it’s moving to the 18” wheels. What a bl**dy shame. I love those 108s.
 

andyglym

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Thanks @Sean d So I’m just describing what is good old-fashioned tramlining then? I’ll take a look at the suspension. But timing wise I suspect it’s moving to the 18” wheels. What a bl**dy shame. I love those 108s.
I'm on 18's Robert. Since I've had my shocks, springs, top mounts and Avon's on, zero tramlining.
 

Sean d

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Thanks @Sean d So I’m just describing what is good old-fashioned tramlining then? I’ll take a look at the suspension. But timing wise I suspect it’s moving to the 18” wheels. What a bl**dy shame. I love those 108s.
My issues started when I fitted the 108s, once I got all the suspension done, it all but eliminated the problem, thats why I am sticking with 17s on the 2.8
 

mrscalex

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My issues started when I fitted the 108s, once I got all the suspension done, it all but eliminated the problem, thats why I am sticking with 17s on the 2.8
I think you are 1 step ahead of me and I'll have to follow you.
 

Bampz

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Thanks @Sean d So I’m just describing what is good old-fashioned tramlining then? I’ll take a look at the suspension. But timing wise I suspect it’s moving to the 18” wheels. What a bl**dy shame. I love those 108s.
Had issue when I first had my z she is on 17s , changed the front tyres as the originals were quite old and the tread pattern was semi directional with about 3/4 mm tread depth
New tyres with same pattern across the tyre and no more issues
 

mrscalex

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Had issue when I first had my z she is on 17s , changed the front tyres as the originals were quite old and the tread pattern was semi directional with about 3/4 mm tread depth
New tyres with same pattern across the tyre and no more issues
Cookies has done about 2,500 miles since I dropped the new engine in last summer and replaced much of the front end setup. Tons more miles than I ever expected to. And I never intended to keep her long term either.

But she’s been such a happy little car and we’ve put so much time into her we’re going to keep her long term. So she’ll come off the road for a rest at some point in the next few months (my other projects need a look in too :) )and have new shocks all round. We’ll see if that allows me to continue with the 108s.
 
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