Engine mount inserts ... don't !

[Radman]

Originally Posted by 78F350

I didn't notice any increased vibration as compared to a new 'Lemforder' replacement bushing that I've used in the past as a replacement. Most of the engine mounts that I've replaced have been done soon after purchasing a car and the old mounts were shot. That makes it hard to do a head to head comparison, but I'm quite satisfied with the Powerflex bushing.

Pics because I like to post pics...

Thanks for the feedback. Strongly considering the Powerflex bushing myself.

[10/10ths]

....you will just lose power.

The stiffer motor mounts trigger the knock sensors and the engine management will retard ignition timing to prevent what it thinks is detonation.

I’ve seen dyno tests to prove it.

I promise you that every Porsche out there with inserts or polyurethane bushings in their motor mounts now own slower cars.

So if you want more noise/vibration/harshness AND a slower car, by all means, send your hard earned money to the aftermarket purveyors who feast on all of the uninformed new Porsche owners who are now buying these old cars because they have depreciated to the point where they are cheaper than new Corollas.

You have been warned.

Just don’t do it.

Cheers.

[78F350]

Originally Posted by 10/10ths

... I’ve seen dyno tests to prove it.

I promise you that every Porsche out there with inserts or polyurethane bushings in their motor mounts now own slower cars. ...

If that's the case - and I'm not arguing, I'm enjoying driving my slower car fast.

Are any of the dyno comparisons documented and available? I enjoy reviewing details and statistics to to learn and arrive at my own conclusion.

[GLImages]

Originally Posted by 10/10ths

....you will just lose power.



The stiffer motor mounts trigger the knock sensors and the engine management will retard ignition timing to prevent what it thinks is detonation.



I’ve seen dyno tests to prove it.



I promise you that every Porsche out there with inserts or polyurethane bushings in their motor mounts now own slower cars.



So if you want more noise/vibration/harshness AND a slower car, by all means, send your hard earned money to the aftermarket purveyors who feast on all of the uninformed new Porsche owners who are now buying these old cars because they have depreciated to the point where they are cheaper than new Corollas.



You have been warned.



Just don’t do it.



Cheers.

If you can see the effects on a dyno, I would think you would be able to see this in durametric. Should be easy to test I think. Can you see what the cams are doing live with a durametric? I don't have one, so not sure. If so the ecm should be pulling timing when detecting knock right? Drive around with durametric running, what does the timing do?

Question, do porsches of this year show 'pending' codes? My other cars do, but are newer canbus cars. I would think there would be at least a 'pending' code if it detects any knock at all, then sets a full blown code once it hits the requirements (whatever those are, detection during a certain # of drive cycles, etc).

[edc]

I'd be imlpressed if somebody has done back to back Dyno runs on the same car showing before and after a change of engine mount and has posted the plots for consumption!

[djw8282]

Originally Posted by 10/10ths

....you will just lose power.

The stiffer motor mounts trigger the knock sensors and the engine management will retard ignition timing to prevent what it thinks is detonation.

I’ve seen dyno tests to prove it.

I promise you that every Porsche out there with inserts or polyurethane bushings in their motor mounts now own slower cars.

So if you want more noise/vibration/harshness AND a slower car, by all means, send your hard earned money to the aftermarket purveyors who feast on all of the uninformed new Porsche owners who are now buying these old cars because they have depreciated to the point where they are cheaper than new Corollas.

You have been warned.

Just don’t do it.

Cheers.

Hey 10/10ths.

I will be pulling my Powerflex engine mount. The vibration is too harsh coming from this area. Question for you. When you say lost of power from engine mounts, are you saying Transmission mounts as well?? I have Rennline trans mounts and I'm not sure if I want to pull those as well.

By the way I have a Durametric. I didn't see any underlying codes. Maybe someone can direct me what to look for if theres a knock sensor issue. Thanks.

[djw8282]

Thanks JFP,

That answer my questions. I will most likely set the semi-solid trans mounts to the softest setting and take out the front engine mount. Thanks

My question is this, why do race cars have more aggressive mounts? Does it detract performance as well?

Thanks.

[djw8282]

Gotcha, thanks for the detailed explanation.