severe vibration after t5 swap

[manicmechanic007]

Damn straight, You never want poly mounts unless you are going racing and not worried about vibration
Used to run solid (steel) mounts in an old 69 Camaro. Could hardly drive the car on the street

 

[AeroCoupe]

I have urethane engine mounts, urethane transmission mount, and urethane transmission crossmember mounts and have little to no NVH in either of my cars. If it's done right i.e. balanced and aligned then you can run motor plates and drive it on the street and not have much vibration.