I was curious if anyone has any tangible (or theoretical) evidence regarding the effects of running stiffer engine mounts on manifold longevity? Will the added stiffness help/hurt/not have an effect?

 

Most data will be anecdotal, but in theory it could change the resonance frequency of the manifold, for better or worse depending on the design.

 

Having stiffer mounts will affect when you have a long manifold.

We only install the side that the motor torque.



Fernando @ Kings Performance

 

^^^ any more info on this?

 

More prone to cracking? Or will the vibrations be better dispersed through the chassis?

 

I appreciate your ambiguous answer

 

I have also pondered this.


I can't imagine anything can be worse than broken stock mounts as the excess movement is translated down your exhaust, and torques on the mani.

Flex-less downpipes crack manifolds almost instantly.

I don't see why stiff mounts and a nice flex section would be any worse. Certainly interested to hear what others have to say.

 

fwiw, I do have a sidewinder manifold, but will be running an uppipe through the hood.

 

It's ambiguous because there aren't too many people that have actually done legitimate testing to see if there is a correlation between harder mounts and increased cracking etc.. I was just saying that in theory, changing a motor mount could change the frequency that the manifold would resonate at. I haven't done anything with my mounts because I like driving a car that still resembles a street car, but everyone has their own priorities when building a car.

 

It's ambiguous because there aren't too many people that have actually done legitimate testing to see if there is a correlation between harder mounts and increased cracking etc.. I was just saying that in theory, changing a motor mount could change the frequency that the manifold would resonate at. I haven't done anything with my mounts because I like driving a car that still resembles a street car, but everyone has their own priorities when build a car.
[/quote]
I definitely agree with the highlighted assertion; just wondering if the resultant change is positive or negative.