Semi Solid Engine Mounts
#1
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Was looking at semi solid engine mounts (65 -75 shores) for 2008 car, but my tuner has discouraged. Says it can trigger knock sensors and pull timing.
65 shores would be the softest of semi-solids and I thought knock sensors would only trigger with the stiffer semi solids or solid mounts ?
65 shores would be the softest of semi-solids and I thought knock sensors would only trigger with the stiffer semi solids or solid mounts ?
#2
Racer
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Was looking at semi solid engine mounts (65 -75 shores) for 2008 car, but my tuner has discouraged. Says it can trigger knock sensors and pull timing.
65 shores would be the softest of semi-solids and I thought knock sensors would only trigger with the stiffer semi solids or solid mounts ?
65 shores would be the softest of semi-solids and I thought knock sensors would only trigger with the stiffer semi solids or solid mounts ?
#3
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Thanks, did not think of those. Have you got them and how do you find them ?
#4
Racer
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Yes, I have the basic FF stage 1 upgraded oem engine mounts on my 997.1tt 6spd. They do a very nice job of controlling engine movement, providing a "bolted down" feeling to the drive train and without any noticeable increase in nvh....perfect for my spirited street use. Having ridden in a friend's 997tt with semi- solid mounts, I didn't like the excessive nvh. It might have felt slightly tighter at 9/10s but for anything other than track or autox, they were simply unnecessarily harsh, IMO.
Bc my 14k MI 13 yr old car was still on original mounts, I also decided to replace the entire factory transmission mount adding FF stage 1 inserts. They make 2 stiffness levels, I chose the softest "stage 1" versions and it works great.
Adding the FF stage 1 engine mounts and transmission inserts along with a new oem trans/mount, made a big difference in the car....drives better, handles better, shifts better, seems to respond better....highly recommend.
TOTAL cost for all the parts was $800.
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Rig.Stunts (08-13-2020)
#6
Rennlist Member
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I think the knock sensor stuff applies to solids or maybe the hardest setting Rennline adjustables. My first mod was some Wevo semi-solids (same as RSS I believe), I highly recommend them. I've heard they wear out but I have 3 years on mine and they're still tight. It's a relatively cheap and easy mod that noticeably tightened up the rear. My originals were pretty old so they were probably due anyway. They did add a little NVH, but in a good way that I'd characterize as "rawness" - I'll never understand the people who want these cars to be luxury cocoons.
Also recommend the FF transmission mount insert.
Also recommend the FF transmission mount insert.
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Frykman_991.1 (03-24-2024)
#7
RL Community Team
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I think the knock sensor stuff applies to solids or maybe the hardest setting Rennline adjustables. My first mod was some Wevo semi-solids (same as RSS I believe), I highly recommend them. I've heard they wear out but I have 3 years on mine and they're still tight. It's a relatively cheap and easy mod that noticeably tightened up the rear. My originals were pretty old so they were probably due anyway. They did add a little NVH, but in a good way that I'd characterize as "rawness" - I'll never understand the people who want these cars to be luxury cocoons.
Also recommend the FF transmission mount insert.
Also recommend the FF transmission mount insert.
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#8
Racer
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When I was doing my research on semi-solid motor mounts one of the issues was that some of the aftmkt mounts, don't remember which ones, had a much smaller surface area where the mount seats to the frame vs stock. Some people reported issues with their particular mounts....so, I chose the FF modified design.
#9
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I also decided to replace the entire factory transmission mount adding FF stage 1 inserts. They make 2 stiffness levels, I chose the softest "stage 1" versions and it works great.
Adding the FF stage 1 engine mounts and transmission inserts along with a new oem trans/mount, made a big difference in the car....drives better, handles better, shifts better, seems to respond better....highly recommend.
Adding the FF stage 1 engine mounts and transmission inserts along with a new oem trans/mount, made a big difference in the car....drives better, handles better, shifts better, seems to respond better....highly recommend.
I figured if you reduce play at the engine mounts, then the factory gearbox mount will be subject to more forces, so would need upgrading.
What sort of power are you running ?
I am keen to stiffen the drivetrain up a bit.
But my tuner reckons if your running higher power, then pushing the motor harder relative to stock and also stiffening the mounts will send the knock sensor past a threshold and cause it to trip.
Any truth to it or just a myth ?
#10
Racer
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No idea regarding truth or myth relative to knock sensors....but I've read the comment numerous times.
I'm completely stock on the power train, but I'm OCD when comes to having a car well maintained and as fresh and perfect as possible....hence upgrading mounts due purely to age of car.
I
I'm completely stock on the power train, but I'm OCD when comes to having a car well maintained and as fresh and perfect as possible....hence upgrading mounts due purely to age of car.
I
Last edited by lflouie; 08-13-2020 at 07:45 PM.
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listnner (08-13-2020)
#11
RL Community Team
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No idea regarding truth or myth relative to knock sensors....but I've read the comment numerous times.
I'm completely stock on the power train, by I'm OCD when comes to having a car well maintained and as fresh and perfect as possible....hence upgrading mounts due purely to age of car.
I
I'm completely stock on the power train, by I'm OCD when comes to having a car well maintained and as fresh and perfect as possible....hence upgrading mounts due purely to age of car.
I
I think the knock sensor issue is a myth with regard to poly mounts.
#12
Rennlist Member
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I have these installed with the medium bushings and don’t experience any knock issues. https://www.rennline.com/Rennline-Tu...oductinfo/M18/
#14
Racer
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https://www.6speedonline.com/forums/...art-nos-2.html
Here is another solution using a Porsche part. The 964 RS motor mount is claimed to offer an noticeable upgrade and the users claim virtually no NVH differences except maybe at idle...after that no change. FYI.
Here is another solution using a Porsche part. The 964 RS motor mount is claimed to offer an noticeable upgrade and the users claim virtually no NVH differences except maybe at idle...after that no change. FYI.
#15
RL Community Team
Rennlist Member
Rennlist Member