Thermostat & Cooling System: Reische Performance

Well honestly your cooling system in it's stock form is not really adequate to handle the heat generated by open tracking. Folks who do it regularly have found it necessary to cut vents into the hood or box in the radiator to increase airflow. Airflow is the key to improving your heat extraction capabilities.

Your thermostat does not keep going bad, the dealer is just applying the simplest solution to the problem. Likely a combination of one or both of these things is happening. First of all if your engine ever overheats and pukes out coolant it MUST be refilled properly every time, procedure here: Ford 4.6L DOHC Coolant Refill & Burp Procedure by Reische Performance Products Otherwise there will be air trapped in the system and you will overheat again shortly, as you've noticed. When the dealer swaps out the thermostat they also burp the system when they refill it which is probably what actually solves the problem.

Second issue is there could be air getting into the system at the cap/reservoir seal. If you've puked out coolant numerous times the cap definitely needs to be replaced but possibly even the whole reservoir bottle. Very hot coolant puking out the overflow around the cap has been known to warp the threads and may prevent the cap from sealing properly over time.

My thermostat may keep the car cooler the first few laps but will not solve your problem because it does not increase the system's maximum heat extraction capability. Replace the cap and reservoir to be safe and running the coolant a bit on the low side to allow additional coolant expansion is actually not a bad idea. Become familiar with the refill procedure and use it if you ever overheat again. You might consider a bit less boost for the track and also run very conservative timing in order to safely deal with the elevated temps. Your only other option is to find ways to increase airflow if you plan to track the car often.

 

This is not a step in my own procedure. It is probably an attempt to move air through the system towards the reservoir, at best it will probably just overfill the reservoir. At worst- if you don't close the cap fast enough you may pull more air back into the crossover. At any rate it is not necessary, you can use the procedure here on my website: Ford 4.6L DOHC Coolant Refill & Burp Procedure by Reische Performance Products

 

That's correct. This happens when there is not enough gas in the reservoir to buffer the hot coolant expansion. The cap releases pressure to a channel around the reservoir threads and excessive coolant will run down the side of the reservoir. A bit unusual as most overflow setups use a hose to neatly dispel excessive gas/coolant to the ground.

Regardless your coolant will level itself properly after several heat cycles.

 

I think there is a temporary issue with Lethal's website. I'll follow up with this to see what's going on. In the mean time you can just call your order in: 877-253-8425

EDIT 7/13/12: Fixed! The thermostats are back on the site.

 

Don't sweat it... sometimes the two halves just pop apart once the housing is opened. Likely it was functioning properly before you removed.

 

No problem... and thank you for following up :thumbsup:

 

Fan settings vary slightly depending upon the programmer you're using, here are the settings for the Terminator:

SCT XCal
Low Fan Speed: 186° (shuts off @178°)
High Fan Speed: 190°

DiabloSport Predator
Fan ECT1 High On: 190°
Fan ECT2 High On: 190°
Fan High Off: 186°
Fan Low Off: 182° (shuts off @180°)
Fan Low On: 184°

Generally your cooling fan should turn on between 184-190° and shut off between 176-182° and proper fan function should confirmed after reflashing your tune.

 

I don't see any changes happening to the 4D model anytime soon so yes, perfection has been achieved... LOL