General rule of thumb is 2,000PSI clamp force for every square of part area at the parting line.
Injection pressure is totally material dependant. You need enough pressure to fill the mold and pack out the part. But not so much that you cause flashing or dieseling. Ask the material supplier.
Dieseling - dieseling makes perfect sense... must be pretty ugly when things go awry! - I've always been intrigued by Injection molding
I interviewed w/an injection molding company in Poughkeepsie NY about 18 years ago, they wanted a international field tech. It sounded fun, but I had no skill w/PLC programming or 3 phase. (tried to BS my way thru it - big mistake!)
Thank god, my current employer saw beyond my lack of knowledge (No more BS from me!) but recognized my willingness to learn.
Learning - something that never ends I hope! thanks for adding to my vocabulary, now off to google Injection molding dieseling!