Alex
Well-known member
- Joined
- 6 Mar 2014
- Messages
- 22,080
After I fit the Powerflex gearbox mount inserts I posted about the transformation it made to the car with regards to handling and NVH and stated that after I'd been on my lads holiday I'd review them and take appropriate action. I'm back off in less than 3 week on another 2.5k trip with my good lady and the dog so wanted to be happy with them before that so yesterday I decided to remove them and do the infrasilver hack.
With regards to the performance of these up to now (after 2 months and around 3k miles) they did bed in more as time/distance went on and the NVH was reduced, but over 3k rpm there was still a considerable amount of vibration through the car and when cruising above 80mph the was quite a drone that wasn't apparent around 70mph. The handling of the car was still as good as when 1st fitted and much better and sharper than with the original old saggy bush. So with this in mind and after infrasilver commenting on his after his eurohoon it spurred me on to do it.
I took a few snaps whilst doing it so folk can see how it works, the issue with them and what the process is, etc.
I didn't have much of an issue fitting them and the carriers were a nice solid fit over the outside of the inserts. When I came to remove them yesterday, you can see patterns on them where the longitudinal carrier has clamped around the outside of the insert and started to bed in. Also bedding in pattern on the inside of them where the gearbox casting has been tight against them. At this point I realised this was most likely the problem with the NVH and needed to be removed. The top part of the insert (where infrasilver cut out the middle section) was also showing evidence of been clamped too rigid. You can see on the photos where the inserts have gone brown where they have been clamped most (as well as indentations in the rubber surface on them - harder to spot on the photos but noticeable when looking 'in the flesh').
Once the 'hack' was done, refitting was simple enough and they went in far easier than when 1st fit. Everything bolted back up, undertray fitted, then out for a blast to review the change.
Wow!! Totally different! As soon as I turned the engine over to drive the car off my ramps I noticed instantly that there was less transfer of engine/gearbox vibration into the car. Took if for a spin down the local A road and the drone above 80mph had totally gone. Turned off onto one of my local twistys an gave it some. The NVH experienced above 3k rpm also totally gone and the deceleration vibration between 4k down to 3k removed. Car still feels nice and tight and the handling just as good. Was quite pleased with the result of doing this as originally although they improved the handling of the car, the NVH was just a tad too much. Looking forward to my next trip down the SoF and will post any update after that.
Here's a few snaps of the process:
The inserts fitted before the modification.
Carriers & insert removed to expose the original bush.
Inserts after removal - notice the brown staining on the top tabs and the ring around the outside of them where the gearbox housing has pressed into the rubber.
The external faces of the inserts. Also notice the depression made by the carrier that runs (on the left one) from the full width of the aperture to the top right outer edge around the 2 o' clock position.
The Hack - I decided to trim a circular pattern that was within the circular clamp mark made be the casing of the gearbox so no transfer of vibration would occur.
Surplus to requirement - notice the indentation where the inserts has been too tight a fit.
Refitted back in position ready for the carriers to go back on.
All back together and ready for the test drive.
Now the countdown to the proper test drive in 3 weeks!! :thumbs:
With regards to the performance of these up to now (after 2 months and around 3k miles) they did bed in more as time/distance went on and the NVH was reduced, but over 3k rpm there was still a considerable amount of vibration through the car and when cruising above 80mph the was quite a drone that wasn't apparent around 70mph. The handling of the car was still as good as when 1st fitted and much better and sharper than with the original old saggy bush. So with this in mind and after infrasilver commenting on his after his eurohoon it spurred me on to do it.
I took a few snaps whilst doing it so folk can see how it works, the issue with them and what the process is, etc.
I didn't have much of an issue fitting them and the carriers were a nice solid fit over the outside of the inserts. When I came to remove them yesterday, you can see patterns on them where the longitudinal carrier has clamped around the outside of the insert and started to bed in. Also bedding in pattern on the inside of them where the gearbox casting has been tight against them. At this point I realised this was most likely the problem with the NVH and needed to be removed. The top part of the insert (where infrasilver cut out the middle section) was also showing evidence of been clamped too rigid. You can see on the photos where the inserts have gone brown where they have been clamped most (as well as indentations in the rubber surface on them - harder to spot on the photos but noticeable when looking 'in the flesh').
Once the 'hack' was done, refitting was simple enough and they went in far easier than when 1st fit. Everything bolted back up, undertray fitted, then out for a blast to review the change.
Wow!! Totally different! As soon as I turned the engine over to drive the car off my ramps I noticed instantly that there was less transfer of engine/gearbox vibration into the car. Took if for a spin down the local A road and the drone above 80mph had totally gone. Turned off onto one of my local twistys an gave it some. The NVH experienced above 3k rpm also totally gone and the deceleration vibration between 4k down to 3k removed. Car still feels nice and tight and the handling just as good. Was quite pleased with the result of doing this as originally although they improved the handling of the car, the NVH was just a tad too much. Looking forward to my next trip down the SoF and will post any update after that.
Here's a few snaps of the process:
The inserts fitted before the modification.
Carriers & insert removed to expose the original bush.
Inserts after removal - notice the brown staining on the top tabs and the ring around the outside of them where the gearbox housing has pressed into the rubber.
The external faces of the inserts. Also notice the depression made by the carrier that runs (on the left one) from the full width of the aperture to the top right outer edge around the 2 o' clock position.
The Hack - I decided to trim a circular pattern that was within the circular clamp mark made be the casing of the gearbox so no transfer of vibration would occur.
Surplus to requirement - notice the indentation where the inserts has been too tight a fit.
Refitted back in position ready for the carriers to go back on.
All back together and ready for the test drive.
Now the countdown to the proper test drive in 3 weeks!! :thumbs: