Hi.

Does anyone know if using solid engine mounts in a 996 GT3 actually does trigger the knock sensors and thus robs the car of power, or is this just a sales pitch from those selling semi-solid mounts? I have the Rennline solid mounts in my car, but I haven't done any data logging (yet) to see if the knock sensors are doing anything they shouldn't.
Anyone that have checked this first hand?

 

There are a few variables from what I understand. As the knock senor measures sound, all sounds in the engine bay could potentially trigger it. If you have a light weight fly wheel, changed exhaust, custom suspension and etc. the trigger point may happen more often. I have not been able to test on my own car, but the best thing to do is put them on and do a real world testing on your own car as each would be different.

That's what I will be doing if/when I get around to putting those parts in (i.e., LWFW, engine and transmission mounts). However, I will only go to semi solids.

 

I am interested in finding out more about this as well.. I also have a set of Rennline solid mounts but have yet to install it..

 

I will do some logging when I get the car out after the winter, but that is still a couple of weeks away.

 

Great, thanks for doing it!

 

On 996TT's and GT3s I've personally seen it trigger the knock sensors. It all depends on what "solid" is if you know what I mean. The wevo with yellow inserts are a-ok. The rss semi-solid also...

 

We are talking about the full solid, metal-to-metal Rennline unit. If that's a problem, I think we should provide the proof to Rennline...

 

I haven't seen or used those and these are all made differently so without testing it on all the cars it would be hard to say. I think we should ask them which cars they have used them on etc...

 

I have the Rennline, my car has been dyno tuned and the tuner would have seen a knock in the results. I will continue to use them.

 

That's a good point of reference

 

When mikymu had his GT3RS, he had a brief review of the Rennline's. He's not here frequently, but I'm sure he'd have additional info.

https://www.6speedonline.com/forums/...nt-review.html

 

Cars: 996 Turbo Cab and 997.1 Turbo.

Short answer: NO KNOCK SENSOR issues so far. Driven roughly 3,000 miles on the 996tt and 600 miles on the 997tt.


I Installed Rennline solid motor mounts on both my cars, these are the ( metal to metal ) mounts, no cushion whatsoever.

1. The mounts Lower the engine roughly 1/4 - 3/8 of an inch. Be careful of the exhaust tips on the 997.1 turbo, they will rub on the bottom of the frame surrounding the exhaust tips during installation, not sure if stock exhaust tips are adjustable, I have the CarGraphic exhaust and had to adjust the tips so they would not rub.
2. The hardware ( bolts, nuts and washers are included in the kit) bolts are fine, nuts and washers in the kit are useless on the 996 turbo and 997 turbo , you will need thicker/larger washers and a nuts with washer attached like the OE nut. I purchased washers and nuts from Lowes Hardware.
3. NO KNOCK SENSOR issues so far. Driven roughly 3,000 miles on the 996tt and 600 miles on the 997tt.

Impression:
Pros....
* I truly enjoy the high frequency sound of the engine now, its harmonic bliss.
* There is more vibration within the cabin, especially on cold starts. The engine is alive and you will feel it in a positive manner if searching for a race car feel.
* Revving slowly through the RPM range feels wonderful as each range brings upon a different frequency that enlightens the driving experience.
* The entire car will feel more planted and sharp, less sway at the rear.
* Downshifts are sharper.
* Engine sounds tighter.

Cons...
* -Not great for long distance daily driving. I drive my cars an aggregate of 400 miles per month, each outing is for the visceral experience, the solid mounts provide the raw, visceral experience at a high level.