Here is the cheap and most efficient way how to make it good "racing engine and transmission mounts" using Polyurethane Casting Rubber. I used Shore A70, but you can use anything between 60-85, everything below that will be too soft, and above will be too stiff...
Cut this and remove the oil from the inside...Properly clean, I used brake cleaner because it's very easy to use ...
Same for the other one...In the time you are waiting for this one to cure enough you can continue with the rest of the mount you can prepare and do another one...
Carefully mask this side.
Slowly pour the casting rubber.
When the first one is cured enough that you can handle it.Depends on the product, but mine take less than 10 minutes to dry on the touch...Take and mask this side.
Casting rubber is coming with component A and component B. How much do you need it?
For the middle part, we cut and removed oil you need around 100g for the main holes on the mounts you need around 230g for both of them... A+B=560g