Correct engine coolant temperature

[Tyler Townsley]

Originally Posted by QB93Z

My next research attempt is going to be replacing the thermostat (which also has the bypass flow valve built into it. I may even try to block off all the low rpm bypass flow just to see what happens.

Jim

You will blow your head gaskets! The thermo temp spring opening depends on the hot water coming down the bypass to see opening temerature. No hot water, no open, blow head gasket.

You can cut the thermo pill spring and block the bypass, this will result in the coolest operating temps.

http://www.deliquescence.net/~tyler/misc1/Thermo.jpg

Tyler

[USAFPILOT]

At what temp would damage to the engine occur? That seems to be more important than who's car runs the coolest and why?

[Tyler Townsley]

Originally Posted by USAFPILOT

At what temp would damage to the engine occur? That seems to be more important than who's car runs the coolest and why?

You get over 260 for any length of time and depending on the age/miles of the engine bad things begin to happen. The location of the water temp pickup can result in a misleading temp on the guage if there is low water in the motor. It is one of the first locations to see steam vic water which results lower temp reading. You need to watch oil temperature reading too.

Tyler

[tomtom72]

Jim thanks for the recco on Mr Haibeck's chip....I've been willing to live with it till now. It's just no fun any longer having to stop playing when the temps start to rise and wait for the stock programming on the fans to do it's cooling job. I get really paranoid when the oil temp gauge gets to 1/2 way and the water temp gauge stays at 3/4 or more! It just scares the chit outta me. I swear I can't get my head around when my C5 & C6 buddies push it till the DIC tells them "reduced power mode/ temp warning"....I'd have had two heart attacks by that time!

I guess I'll ask Mr. Haibeck if I could buy a prom with the fan programming changed to what he says it should be.

[8upZR1]

QB,
96-2000 Ford Mustang 4.6L uses the same style t-stat with bypass valve but it doesnt have the cutouts. I used one for a while and didnt notice any difference. If you get rid of the bypass you wont have coolant flowing through the block when the t-stat is closed.

[QB93Z]

Thanks 8upZR1. I will get one of those without the notches and drill a hole to keep the temperatures equalized. Then I should be able to reduce the bypass flow at low enginr rpm.

Bob, Regarding the question of maintaining low engine temperature at idle, my 1993 will do that. I never could leave the car idling before I replaced the radiator. Now I can. Coolant temp stays at 198. I guess the engine heat load at idle is enough lower than the engine heat load at 1600 rpm and 50 mph that the limited radiator flow can keep the coolant temp down at idle.

Tyler, Thanks for the input. Do you think that a small hole drilled in the body of the thermostat would allow enough flow to ensure that the thermostat does respond to coolant temp?

Jim

[jonszr1]

you might try drilling 2 1/16 in holes along the edge of the thermastat just inside the rubber seal. it takes the car longer to heat up. i did this with the 92 and the car with a 180 stat runs 182-184. i tried 3 holes but the car wanted to run below 180 which i didnt want on an alluminum engine

[rkreigh]

I have a 165 thermostate (zr-1 speciality products) if anyone needs it $100

reprogram the fans, or you can install a switch to control it manually.

I have the big ron davis rad, and the only time I run hot is with the ac on creeping along for 30 min in traffic in 90 deg weather

revving the car up helps, or turning off the ac

pete did an interesting thing and went to an electric pump

not as much flow and not a mod for racing but it increases flow at idle and seems to keep the car cool under normal driving

with the big radiators they "recover" much quicker once you get moving, but they don't work well at low speeds because the fans have a hard time pulling the air throught the much thicker cooling stack

anyone know of bigger better fan setup??

[Kb7tif]

Originally Posted by rkreigh

I have a 165 thermostate (zr-1 speciality products) if anyone needs it $100

reprogram the fans, or you can install a switch to control it manually.

I have the big ron davis rad, and the only time I run hot is with the ac on creeping along for 30 min in traffic in 90 deg weather

revving the car up helps, or turning off the ac

pete did an interesting thing and went to an electric pump

not as much flow and not a mod for racing but it increases flow at idle and seems to keep the car cool under normal driving

with the big radiators they "recover" much quicker once you get moving, but they don't work well at low speeds because the fans have a hard time pulling the air throught the much thicker cooling stack

anyone know of bigger better fan setup??

Interesting. Thanks

[gbrtng]

Originally Posted by salvatore1

my A/C definitely comes on cold. I did notice the drivers side fan was hard to turn with my hand, then it felt like it broke loose and I could turn it again. I see two relay looking things together on the left side of the fan shroud - are these the two relays?

There was probably a rock between the fan and the housing which will stall the fan motor and blow the fusible link at the connector at the rear of the battery.
Replace the link with the correct gauge wire or an in-line fuse - a 30 amp fuse will do the job. And yes, those are the two fan relays.