Solid Engine mounts for 997's
12-17-2009, 04:11 PM
#1
Solid Engine mounts for 997's
Looking at putting solid engine mounts in my car for the track.
Looks like there are 2 options for 997 models:
1. WEVO Semi Solid Mounts
2. Rennline's new SOLID Mounts
Need help from you guys deciding.
Looks like there are 2 options for 997 models:
1. WEVO Semi Solid Mounts
2. Rennline's new SOLID Mounts
Need help from you guys deciding.
12-17-2009, 04:24 PM
#2
Race Car
I had Wevo's in my 996. If you use the car at all for anything outside of the track I'd go with them over the completely solid mount.
The engine vibration increased a good bit at upper RPM's even with Wevo's softer black pillow option in my car, yet did a great job of cutting down on motion of the drivetrain. At idle and low RPM's they weren't bad at all. If you're really hard cord go with their standard pillows.
Andy
The engine vibration increased a good bit at upper RPM's even with Wevo's softer black pillow option in my car, yet did a great job of cutting down on motion of the drivetrain. At idle and low RPM's they weren't bad at all. If you're really hard cord go with their standard pillows.
Andy
12-18-2009, 01:08 PM
#5
Race Car
The solids mounts do transmit alot of NVH through the body, I was looking at getting a set recently and was advised against it if the car sees any street time at all.... It will stop any movement in the engine helping with cornering etc (no weight movement at the back end) ....
12-18-2009, 01:20 PM
#6
Rennlist Member
I have Wevo w/ Black pillowing in my old 964 (which I LOVE by the way). At the time it was a tough decision and Wevo's web text for the 964 wasn't that great, making it hard to decide?
Later I saw that Wevo added/created mounts for the 997... I read the web text and immediately thought it was well written and really would have helped my purchase decision... having lived with them for a couple of months, it's exactly Wevo describes them below...
from Wevo:
The WEVO 997 SS Engine Mount is designed to offer more precise control of the drivetrain mass. Our experience with the whole family of SS Mount products has illustrated that most drivers experience the sensation of the drivetrain unit moving relative to the chassis mass. The drivetrain in a Porsche is independently suspended from the sprung mass of the car via the compliance in the engine and transmission mounts. This drivetrain assembly represents approximately 25% of the sprung weight of the car. The opportunity for forces to move the drivetrain comes from many inputs, such as the torque reaction of vehicle acceleration loads, the bumps and variations in the road surface and the lateral forces created in cornering and braking. That degree of independent movement of the drivetrain is responsible for some of the “sloppy” feeling that is evident when the performance envelope of the vehicle is explored. The higher the forces, the higher the deflections in the hydro-elastic mounts, therefore the deflections and movement of the drivetrain mass begin to operate out of phase with the movement of the car as a whole. For Racing the factory eliminate the hydro elastic mounts and install solid engine mount positions – marrying together the mass of the drivetrain and the sprung mass of the car. While solid mounts might be considered a conventional wisdom for a race car, this practice has an enormous impact on NVH (Noise Vibration Harshness) making it totally impractical for a street driven car.
The WEVO 997 SS Engine Mounts skew the performance intentions of the O.E. engine mounts and control movement by allowing smaller deflections under the same loads. Your drivetrain remains “independently suspended” but managed by a much stiffer suspension – much like stiffer dampers, anti-roll bars or springs could replace the original parts in your front and rear axle suspension configurations.
Unlike solid engine and transmission mount systems, the Semi Solid installation has no metal to metal contact and retains sufficient isolation from engine vibrations to protect your sensitive engine control electronics, sound system and instrumentation systems.
Like all deviations from the original design, there is some compromise. In this case the compromise is the potential for extra noise and vibration to heard and felt in the passenger compartment. Our testing has indicated that the change in NVH is a fair exchange for the performance improvement. A tighter feeling chassis, one with quicker left- right response, more predictable gear change precision and stability under braking. In essence, if you have modified your car in any way, loud exhaust, aftermarket suspension, lightweight seats, lightweight interior….any of these systems are just as likely to have increased the NVH quota for your car and the WEVO 997 SS Engine Mounts might be a somewhat transparent addition to your tuning regiment in terms of NVH.
Later I saw that Wevo added/created mounts for the 997... I read the web text and immediately thought it was well written and really would have helped my purchase decision... having lived with them for a couple of months, it's exactly Wevo describes them below...
from Wevo:
The WEVO 997 SS Engine Mount is designed to offer more precise control of the drivetrain mass. Our experience with the whole family of SS Mount products has illustrated that most drivers experience the sensation of the drivetrain unit moving relative to the chassis mass. The drivetrain in a Porsche is independently suspended from the sprung mass of the car via the compliance in the engine and transmission mounts. This drivetrain assembly represents approximately 25% of the sprung weight of the car. The opportunity for forces to move the drivetrain comes from many inputs, such as the torque reaction of vehicle acceleration loads, the bumps and variations in the road surface and the lateral forces created in cornering and braking. That degree of independent movement of the drivetrain is responsible for some of the “sloppy” feeling that is evident when the performance envelope of the vehicle is explored. The higher the forces, the higher the deflections in the hydro-elastic mounts, therefore the deflections and movement of the drivetrain mass begin to operate out of phase with the movement of the car as a whole. For Racing the factory eliminate the hydro elastic mounts and install solid engine mount positions – marrying together the mass of the drivetrain and the sprung mass of the car. While solid mounts might be considered a conventional wisdom for a race car, this practice has an enormous impact on NVH (Noise Vibration Harshness) making it totally impractical for a street driven car.
The WEVO 997 SS Engine Mounts skew the performance intentions of the O.E. engine mounts and control movement by allowing smaller deflections under the same loads. Your drivetrain remains “independently suspended” but managed by a much stiffer suspension – much like stiffer dampers, anti-roll bars or springs could replace the original parts in your front and rear axle suspension configurations.
Unlike solid engine and transmission mount systems, the Semi Solid installation has no metal to metal contact and retains sufficient isolation from engine vibrations to protect your sensitive engine control electronics, sound system and instrumentation systems.
Like all deviations from the original design, there is some compromise. In this case the compromise is the potential for extra noise and vibration to heard and felt in the passenger compartment. Our testing has indicated that the change in NVH is a fair exchange for the performance improvement. A tighter feeling chassis, one with quicker left- right response, more predictable gear change precision and stability under braking. In essence, if you have modified your car in any way, loud exhaust, aftermarket suspension, lightweight seats, lightweight interior….any of these systems are just as likely to have increased the NVH quota for your car and the WEVO 997 SS Engine Mounts might be a somewhat transparent addition to your tuning regiment in terms of NVH.
12-18-2009, 02:42 PM
#7
Rennlist Member
Join Date: May 2006
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I have the WEVO 997 SS mounts with the yellow pillow in my '03 996C2 which sees every type of usage from city streets and instructor-level track duty & time trials. The semi solid mounts seem to eliminate all the negative aspects of the liquidy stock mounts (as far as I can tell) with only a moderate compromise in NVH refinement. I have never tried completely solid mounts, but just thinking about them conceptually they seem grossly overkill on anything but a race car. Solid mounts might give you an extra 10% more driveline stiffness, but in exchange you would probably suffer a 90% increase in NVH harshness. If you drive on the street at all, what would be the point of going full-solid when such a good alternative exists?
BTW: If you do a search in the Racing & DE forum for “WEVO mount” you will find my post on the installation of the mounts, including pictures, as well as a lot of other peoples’ posts on the subject
BTW: If you do a search in the Racing & DE forum for “WEVO mount” you will find my post on the installation of the mounts, including pictures, as well as a lot of other peoples’ posts on the subject
