Can you explain what you mean? I modded my Steppy with a PRT mounted up front and had far better temperature control as seen on my Scangauge. Not high at all and I wouldn't expect a standard PRT down the front of the engine to run high temperature either. Are you sure there isn't a standard stat in the engine too? (May have missed that bit if you've already said it is removed)
The car currently runs 92-94C average.
I would like that to be around 82-88 with it closer to 82 so there is a 10C ceiling increase to give the system time to accommodate extra heat.
Currently either someone has fitted the wrong PRT or it just is a bad setup (clogged/busted PRT)
I want to remove the PRT and fit a modified 82C Stat near the radiator with a small bypass so I can run the car harder without fear of temperature spikes.
A 82degree PRT is £40+ whereas an 82 degree stat with bypass (for me) is just in the £20 mark or so.
I already have the non PRT piping so I want to make use of that.
You're right of course, you can fit a PRT up front instead but I do not have an 82C PRT, only a 92C V6 one which I want to use for other reasons.
My last 3 ZS's ran in the ~84 range, my current ZS has a stuck-open stat so runs at 74-78C almost constant, which I can live with as I know it will never overheat on long distance, which I use it for a lot in the summer.
TL;DR PRT is probably the wrong one, I want to fit a radiator stat to make the temperatures even more stable for harder driving, before I sell the car on knowing it's going to be reliable for whoever else uses it.
They are cheap for a reason.
I am perfectly happy with working on the car for what I purchased it for. It isn't costing me anything but experience points and time. Both of which I am happy to invest.
I don't want to buy a perfect car because i'd be complicit in it's reliability until it died completely because I never took it apart to see what was wrong with it.
So far none of the issues have been mind benders. They've just been a long series of troubleshooting stages that left me stumped because I didn't think to check :P
Me being less stupid in future means me wasting less time.