Joshboody

Had Mr. Gasket and now LPE... each only lasted about 5 track days and then seized up (tested in water pot).
Any others have this experience?
2004 pump design.

Think need to go back to stock 190deg, cause this is annoying.

ooldguy93

the following with 160's :

3 seasons in an '02 Z28

3 seasons in an '96 LT4

3 seasons in an '03 Z06

1 season ( so far ) with a 5.3L Miata

all no issues, all from various suppliers

froggy47

10 years with a Lingenfilter no issues.

When you test are they sticking OPEN or CLOSED?

What is your symptom overheating or not warming up?

Bill Dearborn

Stock thermostat will provide plenty of cooling on the track. All the thermostat does is set a floor temp doesn't do a damn thing to keep the engine cooler. If your on track coolant temp is 200 deg it doesn't really matter whether or not you have a 160 or the stock 186.

Bill

NemesisC5

I don't remember all the details but have been told that when using a thermostat you can bypass at higher rpms/higher pressure and some coolant will not flow through your main radiator. An engineer at Evans Cooling advised that summer track events are best without a thermostat at all. I remember Anthony from LG saying they race their cars without thermostats. Maybe someone can chime in with explanation regarding the bypass.

froggy47

It's not bypass so much as a restriction. Even a wide open thermostat (of any set temperature) is something of a RESTRICTION to the overall flow of coolant, pull one out and take a look at it and then take a look at the hole it sits in. So take the whole thing out (for racing) and you get better overall flow (gallons per min.) Of course for non race/winter/etc. you want one to warm up the coolant and keep it at optimum temp.

NemesisC5

Froggy, I did not explain clearly what the engineer at Evans Cooling stated. His point was that at higher rpm's the fluid pressure pushes against the thermostat and moves it mechanism and diverts coolant into one of the passages in the pump itself. He said for track applications they can block off the passage on their pump before shipment. He also stated that Evans new LS water pumps are now coming with a thicker back cover that will not flex due to higher pressures at high rpms. He stated a factory LS pump can begin cavitation between 5-6k rpms while their unit will not until almost 8k.

Their waterless coolant is also designed around this principal as well preventing air bubbles from cavitation. The flow of coolant without air bubbles around the combustion area carries away more heat than coolant with air pockets. Although the engine coolant gauge may read the same, lower oil temps will reveal that your engine is more efficiently cooled.

Although not explained by me with much detail I'm sure you get the picture.

NemesisC5

Here is a discussion from LS1Tech. If you read down just a few posts the discussion opens up and a few members describe this in detail. Anyone tracking a new C7Z could benefit from this if the coolant system is designed like C5/C6.

http://ls1tech.com/forums/advanced-e...hermostat.html

Joshboody

Thanks for responses... seems not a reg issue. Just unlucky.

They seize closed, so car runs hot but surprisingly doesn't overheat... well 245 on track which is too high.

sccaGT1racer

You can remove your thermostat but you will need a restrictor in its place. If the coolant has no restriction it will not be able to transfer heat from the engine to the radiator.

NemesisC5

Actually in the link it suggests to block off the passage under the thermostat and that removing the thermostat without doing so will indeed result in running hot or over heating.

I copied and pasted the below from the link above.

"After a cold-start, coolant is pulled through this bottom (bypass) passage which includes the heater-core feed line as well. When the tstat is closed, the bypass valve (extra thing hanging off the bottom of the tstat) is wide open. With the bypass open the pump will be recirculating the coolant from the block right back into the block to speed up the warm-up cycle.

As the tstat opens, the bypass valve closes off the bypass passage. The heater-core feed still gets hot coolant from the block which makes its way through the heater core. Everything else (coolant) from the block must get pumped through the radiator before getting back to the tstat housing and being pumped back into the block again.

Key point here AGAIN:
If you remove the tstat, you are also removing the bypass-valve which leaves the bypass passage WIDE open. This will allow at least 30% of your coolant to get pumped back into the block without ever seeing the radiator. This WILL make you run hotter.

For those of you that removed the tstat and/or tried a restrictor, try again!

This time block the bypass passage so you don't overheat.

What you will find is that you will run MUCH cooler than you did with a tstat in place.
You can start a 1/4 mile pass at 150*F and end your pass at 150*F, NOT at 200*F like the tstat will force. It will make your cool-down cycle MUCH quicker too."

froggy47

I would do the boiling water test again & then (carefully with gloves) examine the stuck stat and see exactly where/why it does not open.

Here is another test.


BTW my 10 year old stat is a HYPERTECH PowerStat 160, sorry for the mistake in earlier post.

chetly

So with a stock radiator, the thermostat removed and the bypass blocked, would that still cool as well as thermostat installed with an aftermarket radiator(your choice)?

Joshboody

I thought the restrictor is more for pump head pressure than coolant flow.

Which maybe enough restriction is created by blocking the bypass... but seems somewhat involved to block it.

froggy47

I don't think anyone is saying that. If it's true then boy, are we a bunch of idiots for putting $1000 radiators in the cars.

chetly

That's why I asked the question...

NemesisC5

With the bypass blocked you will move 100% coolant through radiator. With thermostat in place and open I was told we only move ~70% of coolant through radiator. To answer your question best I can, I don't know but it's a good bet your cooling would improve a noteworthy amount. Of course that will have drawbacks in cold weather getting car up to operating temps and your heater not getting as hot or hot as quickly as before.

NemesisC5

Pressure and flow are two separate variables. Water expands with heat and even with engine not running pressure remains until your coolant falls to a certain temp somewhat influenced by ratio of ethylene glycol / water mixture.

Flow is how much volume your water pump moves coolant mixture through your entire system. Head pressure will decrease flow.