RS Motor Mounts DIY w/ Pics and Part Nos.
#16
10-07-2011, 11:32 PM
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Nice writeup.
I did the Wevo semi-solid mounts and 997T tranny mounts (found one of the original tranny mounts was actually damaged while replacing). My initial impression was that there was minimal effect on ride quality and really did like the togetherness of the whole package. At the time I was driving the car a lot less. I go through these cycles where the Porsche is more of a weekend car, and then I might drive it pretty often for a while.
Months later, specifically after taking a few long (2-3 hour) trips and generally using the car a bit more regularly, I am increasingly feeling that the engine mounts in particular have had a significant adverse effect on the "jiggliness" of the car at all speeds. I am seriously thinking about going back to stock or maybe X73 or GT mounts.
The 964 engine mounts seem to have more rubber than the Wevo and I assume better isolation.
When I think about it, the fact that Porsche has put significant R&D into developing the latest dynamic engine mounts suggests that stiffer mounts do have a significant effect on ride quality as well as precision and handling feedback. It's amazing how technology allows you to have your cake and eat it too. The latest cars have electronic shocks, engine mounts, etc... giving all models a range of settings spanning the comfort/sport zone. I can imagine cars may at some point have dynamic engine, tranny & shock mounts + suspension bushings etc...
I did the Wevo semi-solid mounts and 997T tranny mounts (found one of the original tranny mounts was actually damaged while replacing). My initial impression was that there was minimal effect on ride quality and really did like the togetherness of the whole package. At the time I was driving the car a lot less. I go through these cycles where the Porsche is more of a weekend car, and then I might drive it pretty often for a while.
Months later, specifically after taking a few long (2-3 hour) trips and generally using the car a bit more regularly, I am increasingly feeling that the engine mounts in particular have had a significant adverse effect on the "jiggliness" of the car at all speeds. I am seriously thinking about going back to stock or maybe X73 or GT mounts.
The 964 engine mounts seem to have more rubber than the Wevo and I assume better isolation.
When I think about it, the fact that Porsche has put significant R&D into developing the latest dynamic engine mounts suggests that stiffer mounts do have a significant effect on ride quality as well as precision and handling feedback. It's amazing how technology allows you to have your cake and eat it too. The latest cars have electronic shocks, engine mounts, etc... giving all models a range of settings spanning the comfort/sport zone. I can imagine cars may at some point have dynamic engine, tranny & shock mounts + suspension bushings etc...
Last edited by Turbo Fanatic; 10-07-2011 at 11:38 PM.
#18
10-10-2011, 10:43 AM
Guys can you plz tell me if the 997 GT3RS motor mounts also fit!! I have ordered them in but I need to cancel the order ASAP if its the 964RS ones i need. thanks!!
#19
10-10-2011, 10:44 AM
I had the option of dynamic mounts or normal mounts, i knew the dynamic mounts were for the new cars so opted for the normal ones. i'll check the part number.
#20
10-10-2011, 11:56 AM
Join Date: Dec 2006
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Rep Power: 68 Yeah, I'm sorry, but I don't know anything about whether the 997 gt3 RS units will fit. All I know is that the 964 RS kit is what everyone seems to use if they want a harder edge oem solution instead of going with something like the wevo line of solid or semi-solid products. Good luck!
#23
10-21-2011, 04:27 PM
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Last question and I did do a search on it but there doesn't seem to be a consistent answer. I never ever ever jack the car up by the engine case. It just seem a bit scary given there are several less expensive areas to use. However since I'm going to change the motor mounts I have no choice. So where do you guys recommend to place the jack pad and do you prefer the hockey puck or 2x4 length wise method.
#24
10-21-2011, 04:29 PM
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Transmission Carrier Mount
Code: 99737503303
per Suncoast.
Code: 99737503303
per Suncoast.
#25
10-21-2011, 05:27 PM
Last question and I did do a search on it but there doesn't seem to be a consistent answer. I never ever ever jack the car up by the engine case. It just seem a bit scary given there are several less expensive areas to use. However since I'm going to change the motor mounts I have no choice. So where do you guys recommend to place the jack pad and do you prefer the hockey puck or 2x4 length wise method.
#26
10-21-2011, 05:31 PM
Join Date: Dec 2006
Location: Phoenix, Arizona
Age: 48
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Rep Power: 68 I never jack the car up by the engine. I know guys do it but I wouldn't. Jack the car up on both sides at the factory locations ahead of the rear wheels with two low profile jacks. Then place a jack with a 2x4 length wise along the seam of the engine case right at the oil drain plug and just use the jack to support the engine in place so it doesn't drop as you remove the lower engine mount bolts. Then you can remove the old engine mounts and swap in the RS mounts. After you are done, lower the jack under the engine and then lower the jacks on both sides of the car. When I jack up the car on both sides with jacks I also place two jack stands under the main engine carrier beam just as a safety precaution. They do not support anything but prevent the car from dropping onto you in case one of the jacks failed.
Definately an option. Ironically, I'm told the only component that could conceivably be damaged by repeated jacking from the engine is, in fact, the motor mounts! I've jacked this way for years on several 9x6 porsches, and never had a problem, but as I mentioned above, It would not hurt to do it by jacking from the sides.
#27
11-05-2011, 03:30 PM
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Thanks again for the DYI on this. The only thing easier that this is putting gas in the thing. Due to spider monkey arms and a prehensile tail I was able to do this without help of the wifey.
Last edited by Duane996tt; 04-06-2012 at 09:04 PM.
#29
05-14-2013, 10:25 AM
Interesting. I did not recieve any instructions from Suncoast, nor did I ask. I will note that the illustration you attached appears to have a different engine carrier than the 996tt (it looks like a 964/993 carrier to me, but I could be wrong), so I would question whether that illustration is truly representative of the 996tt installation, or simply an illustration of the 993/964 application. I got my "stack" information from Kevin at UMW who assembles these kits for use on our cars. In any event, I can't imagine using that waster will hurt anything because it will not change the "stack height" of the mount relative to the engine/engine carrier. All the insertion of that washer will do is reduce the number of threads on the mount bolt that extend below the engine carrier (which isn't a big deal at all becaues there is more than enough thread on the end of the longer 996tt bolts to permit full installation of the bottom nut). My take is that you could probably use the washer with no ill effects, but I left it off since Kevin said it was not needed, and from my inspection of the interface between the large gold washer and the head of the through bolt, there is absolutely no need for a washer there (but that's just a guess).
One other clarification....in the attached illustration it indicates the use of a small washer for each of the bolts (two per mount) that hold the mount to the chassis. I would not use those because upon examination, you might not get good thread penetration into the chasssis with those washers installed (not that these bolts thread directly into the aluminum "spacer" that sits in the engine compartment, there is no nut that secures the mount to the chassis). After all, the bolt hole "flange" at this location for the rs mount is approximately the same thickness of the oem bolt hole flange, and the 996tt manual shows that no washers are used at this location and the rs mount kit bolts are the same lenght as the oem bolts, suggesting to me a risk of insufficient thread penetration if you use washers in conjunction with those bolts. Hope that makes sense (it probably will make more sense after you remove the oem mount and compare its shape to the rs mount).
Thanks for adding to the thread! (P.S. For reference I've added a pic I found on another forum that was taken by Kevin (I hope he doesn't mind) that clearly shows his installation, and that the two side bolt washers and the silver washer atop the gold curved washer are not installed).
One other clarification....in the attached illustration it indicates the use of a small washer for each of the bolts (two per mount) that hold the mount to the chassis. I would not use those because upon examination, you might not get good thread penetration into the chasssis with those washers installed (not that these bolts thread directly into the aluminum "spacer" that sits in the engine compartment, there is no nut that secures the mount to the chassis). After all, the bolt hole "flange" at this location for the rs mount is approximately the same thickness of the oem bolt hole flange, and the 996tt manual shows that no washers are used at this location and the rs mount kit bolts are the same lenght as the oem bolts, suggesting to me a risk of insufficient thread penetration if you use washers in conjunction with those bolts. Hope that makes sense (it probably will make more sense after you remove the oem mount and compare its shape to the rs mount).
Thanks for adding to the thread! (P.S. For reference I've added a pic I found on another forum that was taken by Kevin (I hope he doesn't mind) that clearly shows his installation, and that the two side bolt washers and the silver washer atop the gold curved washer are not installed).
Sort of a blast from the past but I just wanted to do a quick update regarding these RS mounts. I have had them in for about a year now and absolutely love them, great product. There was a discussion in post #6 of this thread regarding the requirement (or lack thereof) of the thick silver washer to be used in the installation of these mounts. I know the OP did not install these based on someones recommendation as can be seen in the picture of post #6.
Well, I can tell you with certainty that the thick silver washers are an absolute must unless you want the large gold washers to deform over time and cause the mounts to sag. You can see the picture below how the two washers on the left (the ones I removed from my mount) have deformed in the center from the load of the bolt head being concentrated on such a small area. The new washer is on the right. The function of the thick silver washers is to distribute the load over a larger area of the gold washer so that it does not distort and cause the mounts to sag.
So, if you are running these mounts without the silver washers, check them and install them before the gold washers fail. The second picture is of the mount properly installed with both the silver and gold washers in place.
RS engine mount washers by pwdrhound1, on Flickr
RS engine mount in 996tt by pwdrhound1, on Flickr
#30
05-14-2013, 10:34 AM
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WOW! I just checked my gold washers and there indeed appears to be a bit of deflection (not a lot, but definitely there). I'm going to order new gold washers and install my silver washers. Thanks so much for the update!