The Green Lantern

I put a 170* in my 04 GT a couple months ago cause my gauge before would always read 3/4 hot and when i drove without the A/C on I could always feel hot air coming from below by the pedals. Here in texas its obviously gets hot so it usually stays around 180 when its hot.

I have just basic bolt ons, no cats/offroad xpipe, etc, so is there anything I should change to accommodate for the lower temp. I have a diablo tuner and its just set on the 87 performance, might start running 93 again. Other than that though can/should I change spark timing? Car has 115k on it if that matters and is a DD.

Thank You.

Sonic Mustang

What temperature is your car running at with the 170 degree thermostat? You can find out by bringing up cylinder head temperature on the gauge cluster test/trick.

http://www.mustangworld.com/ourpics/fcar/dtcodes.htm

The link at the end of the article explains what you are seeing on the display.

I am reasonably certain that cylinder head temp is actually coolant temp.

My Mach 1 has the stock thermostat and according to the Scan Gauge II plugged into my OBDII port, my coolant temperature normally runs at 190F and a little higher on hot days. The temp gauge stays in the middle.

I think 180F is too cold. I'm wondering if your gauge is off.

fastbackford351

Huh.

How about that?


That's a neat link. I'm going to give try that just for the giggles and grins.

moncherou

170 might be a little too cold and the pistons/rings might not be expanding and sealing like they should or more cold spots than normal (cold is relative). i have a 180 degree thermostat in mine and the temp ranges from 180-200 when i monitor with a tuner. i'd rather stick with stock but with the non-intercooled blower i experienced some problems on hot days which the 180degree thermostat sorta, kinda, helped with

the cylinder head temp is the coolant temp, i believe the sensor makes contact with the coolant where its at in the cylinder head

The Green Lantern

I think the gauge is messed up because when the temp is at 170(confirmed by tuner) it stays right in the middle, but then if it goes up to like 176 it will go 3/4 hot. Today I had the a/c off and the fan isn't programmed to come on till what is normal(200-210) so it got up to about 195 and the gauge still stays 3/4 hot.

Sonic Mustang

A correctly functioning temp gauge will stay in the middle at 205F or more. Put the regular thermostat back in!

LilRoush

If your coolant temp is actually lower than your dash is telling you, then you have an issue with the gauge or the coolant temp sensor.

The 170 thermostat isn't always a bad thing, it will just allow coolant to circulate to the raditator sooner. If you use it, keep your fan temp the same so it won't kick on until the 210F range.

AzPete

The thermostat also must allow the coolant to sit in the radiator long enough to actually cool down. If it opens to soon or to often, the coolant starts on a cycle of never getting cooled properly and that actually raises the operating temps of the cars. There is a balance that must be reached when switching from a stock thermostat especially on a stock car.

The Green Lantern

This might sound dumb but I feel like the car runs stronger and better now with the 170 in it then it did with the stock one. It seems the gauge is messed up but is that something worth really fixing?

Sonic Mustang

If that's the case, why not try a 160, or 150 or....?