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Body wobble with quick direction changes

So the mount in the photo is indeed exactly the same as the original one in my car. I wrote 996 but should have said 993 (curse my clearly decaying mind!) but looking back at my old photo of the original that is precisely the same markings on the ones on my car that I replaced.

Here is my original thread on my engine mounts https://911uk.com/threads/what-engine-mounts-are-these.118313/
 
I've got the RSS Tarmac Series engine mounts in my 997 and would recommend them as adding stability - before that it felt like the engine was all over the place
 
surely that is a 993 mount??
theyre the same. 964/993/996/986/997

generally speaking the part number carries through, but the model number changes

so a 993 mount is 993.375.049.07, and the 996 version is just 996 at the start, 997 version 997 at the start etc, and the rest of the numbers are the same.
Lots of people fit pattern part 993 RS engine mounts like these which are good value and cheaper than the original mounts (with a bit of extra vibration as you would expect for a solid non hydrolastic mount)

 
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theyre the same. 964/993/996/986/997

generally speaking the part number carries through, but the model number changes

so a 993 mount is 993.375.049.07, and the 996 version is just 996 at the start, 997 version 997 at the start etc, and the rest of the numbers are the same.
Lots of people fit pattern part 993 RS engine mounts like these which are good value and cheaper than the original mounts (with a bit of extra vibration as you would expect for a solid non hydrolastic mount)

They are half the price of the 997 parts so look like a good deal!

Mine look like the original, assuming the bottom number is the date of manufacture (mine's a 2010 car).

I've tried the rev test where someone does quick revs on the engine when in neutral (PDK) and the engine doesn't visibly shift a mm, so it looks like they are perfectly fine - unless this test only works for manuals? I'm all for improving the car but not blowing the cash on something that doesn't need changing.
 

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Turn the climate off and look at the headrest of the passenger seat, or lightly put your hand on it, if it is moving at all your mounts are shot. Could well be that.



It sounds more like the geo settings to me or rear dampers are shot, but the rears tend to last years. You can also get this when the rear set up is too soft for the front.

I would get the geo looked at. Maybe ask someone local if they can look at the geo for you, say you are going to fit a few arms and want to see what it is so you have a before and after, many are happy to quickly give you a print out.

My guess is not enough rear toe in on the back.
Might have a bit too much negative camber on the front too, I know everyone loves loads, but it does make the car feel fidgety.
You could mark the three top mounts nuts with marker, undo them, slide them out as far as they will go, which will give you a smidge of negative camber on the front and see how that feels.
It makes the front end feel more planted and less floaty and stops the steering wheel constantly moving around.


I would get under the back as well and just check the rear anti roll bar, make sure there is no play at all, and the drop links if you can, it is amazing how loose this can make the car feel.

Also, don't lift off while turning, there is a lot of weight over the back, once you have committed to a change of direction lifting off, or worse, braking, will really move that back end around. Only do that if you need to turn in quicker.





One last thing. Going to ask a silly question here, and I am sure the answer will be yes, but......Have you got the same tyres fitted on the front and rear?
I have had this where the back feels like it is loose when I had PS4s on the rear and Bridgestones S-02A's on the front when they ordered the wrong size fronts. Back end kicked out slightly just over taking a car in the rain.
 
Turn the climate off and look at the headrest of the passenger seat, or lightly put your hand on it, if it is moving at all your mounts are shot. Could well be that.



It sounds more like the geo settings to me or rear dampers are shot, but the rears tend to last years. You can also get this when the rear set up is too soft for the front.

I would get the geo looked at. Maybe ask someone local if they can look at the geo for you, say you are going to fit a few arms and want to see what it is so you have a before and after, many are happy to quickly give you a print out.

My guess is not enough rear toe in on the back.
Might have a bit too much negative camber on the front too, I know everyone loves loads, but it does make the car feel fidgety.
You could mark the three top mounts nuts with marker, undo them, slide them out as far as they will go, which will give you a smidge of negative camber on the front and see how that feels.
It makes the front end feel more planted and less floaty and stops the steering wheel constantly moving around.


I would get under the back as well and just check the rear anti roll bar, make sure there is no play at all, and the drop links if you can, it is amazing how loose this can make the car feel.

Also, don't lift off while turning, there is a lot of weight over the back, once you have committed to a change of direction lifting off, or worse, braking, will really move that back end around. Only do that if you need to turn in quicker.





One last thing. Going to ask a silly question here, and I am sure the answer will be yes, but......Have you got the same tyres fitted on the front and rear?
I have had this where the back feels like it is loose when I had PS4s on the rear and Bridgestones S-02A's on the front when they ordered the wrong size fronts. Back end kicked out slightly just over taking a car in the rain.

So many good points in this post
 
Tail pipe sag can be subtle. I didn’t even notice mine until I was parked on an uphill slope. It was 12mm between old and new- I’d change the engine mounts. The handling is night and day better.
Your mounts are original as indeed the dates are the date of manufacture of the mount and after this many years they will be knackered.
 
Tail pipe sag can be subtle. I didn’t even notice mine until I was parked on an uphill slope. It was 12mm between old and new- I’d change the engine mounts. The handling is night and day better.
Your mounts are original as indeed the dates are the date of manufacture of the mount and after this many years they will be knackered.


100%.

I completely missed your post with the photo showing original mounts.
I started replying on the train and lost signal and then opened my macbook when I got in and finished my reply.

If they are originals just get them changed. Easy to do on the driveway if you have a jack and only takes 30 minutes.
 
100%.

I completely missed your post with the photo showing original mounts.
I started replying on the train and lost signal and then opened my macbook when I got in and finished my reply.

If they are originals just get them changed. Easy to do on the driveway if you have a jack and only takes 30 minutes.
Excellent points, thank you. (y)
Car booked for 993 semi-solid mounts, geo-check and extra scrutiny of front shocks, track rod and drop links.
 
+1 for the 993 RS mounts. For me, they provided more stability in direction changes, acceleration and gearchanges.

Good luck with the Geo and Suspension Inspection, hopefully they get to the root cause of your handling issues. Copse Automotive in Knaphill (Woking) completed a Fast-Road Geo on mine and in combination with DSC Controller dialed out a lot of the handling feelings you describe.

The standard car felt like the rear was going to lift the rear of the car in faster corners (>70mph) and aggressive overtakes. It felt scary to drive fast
 
Turn the climate off and look at the headrest of the passenger seat, or lightly put your hand on it, if it is moving at all your mounts are shot. Could well be that.
I just did this, not visibly moving but can feel the seat vibrate... So I assume it should feel solid?

Also, these look cheap for OEM engine mounts? https://www.amazon.co.uk/febi-bilstein-34849-engine-mounting/dp/B006DHVLRA/

Is the 993 RS mounts the "best" route for control and without any more NVH?
 
Just replace with Porsche ones from OPC.
I'm not 100% on the seat thing.
Agree. I felt an immediate improvement with new direct-replacement Porsche mounts and temporarily some slight increase in NVH. I can only assume that NVH would increase with solid/semi-solid mounts over the standard ones.
 
Agree. I felt an immediate improvement with new direct-replacement Porsche mounts and temporarily some slight increase in NVH. I can only assume that NVH would increase with solid/semi-solid mounts over the standard ones.
It does. I've got RSS and there is a little bit extra at 2.5k rpm but on balance a small sacrifice for the other benefits imo.
 

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