running warm; not sure why

I've had my tc a couple of months now, during which I have done a few mods. When I got the car it had a cone filter and manual boost controller. Since then I've replaced the timing belt and upgraded the exhaust to a Magna flow straight muffler dumped at rear tire. A couple of days ago it started running warmer. It notoriously has ran with the needle pointed between the R and M on the gauge unless I was under boost a lot. It now is hovering around the middle of O. I'm not sure the temp rage for the gauges so it's hard to say what the current or previous temps are. Fan is operating and no changes have mean made preceding the sudden change. Any thoughts?

My guess would be that your fine. The factory gauge is not very accurate. I would recommend installing aftermarket water temperature and maybe oil pressure too.

Pick up a infared thermometer and you can just point and shoot to see what the temp is. Yes the factory gauges are not very trust worthy.

I have this problem even worse in this desert heat .... My problem is the stock fan switch not coming on till 220 +

is your AC on? Just for G&G (Grins and Giggles), drive along with it off till it's warmed up good then turn it on and see what the temp difference is. When it's 90+ degrees outside here mine gets between the N and the O pretty quickly and stays there. If it's below 85 or so it stays about on the M.

My car runs great at highway speeds...I figure that if the temp is in the normal range nothing is going to get hurt. It idles better when the temp gauge is pointing at the R or above.

My fans are both hard wired on from the PO, one of my goals in life is to make them work like they should.

Also, my radiator has a decent amount of scale buildup in it which may affect things.

That was with both AC on and off (however AC doesn't work). It did go back down to its previous normal temp last night so I'm thinking perhaps the thermostat got stuck half open or some debris was blocking a port somewhere. I think I'm going to replace the thermostat just to be safe.

Short of a warmer engine being a bit more prone to knocking if you're running more-than-stock boost and the factory IC...and then the sensor yanking timing and power falling flat.....nothing is harmed. The factory tune was designed for longevity, efficiency and emissions.....a modern EFI engine just runs better at 200-220 than 180. Sure, you lose a couple horsepower, but fuel economy and engine life are extended....

As long as both fans work and the factory relay and everything are in good shape, leave it alone. If the thermostat hasn't been done in a while, maybe replace it with a new one....but make sure it's the factory spec'd temp! Maybe flush the cooling system, do the water pump and clean or replace the radiator, if you're REALLY worried....but don't muck about with what the engineers did unless you think you know what's better, or you truly value a few peak horsepower over longevity and efficiency...