7mgte running too cool, thermostat help

josbeat

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Ok i have modiffied my engine to run as coolest as possible and now I have problems!!! jejeje

My mods are a double line routed from the back of the head, no turbo cooler line, inline thermostat housing with 80ºC BMW big thermostat on a upper radiator hose, Ebay bigger radiator cooler, flexalite electric fans, no thermostat on stock location, throtle body warmer lines routed to the thermostat housing, 50% wurth coolant and a cooling plate cover plus two hood vents.


the problem is .... running with the car on the higways the tempture is going up and down constantly from 86º to 70ºC , on a track I never get more than 84º which is my goal , the problems is when I am going to the track on a legal speeds.
I tryied with the stock thermostat, with the Summitracing 80ºC thermostat and now I have a modiffied BMW 80ºC thermostat.

a provisional solution is to cover the half of the front radiator .... but not the ideal

anyone have a idea of what thermostat could be good??
or what is the problem, way the thermosta can´t keep the temperature stable??

photos

here is where the second line is attached, to the thermostat cap, it have an elctric pump also to help moving the whater when the fans is runnig and also after stop the engine.

here we can see the inline thermostat
 
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Nick M

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Thermostat maintains minimum temperature. Not max. Get a higher rated unit. I didn't look at your pictures, just the comment about covering the radiator.
 

josbeat

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Thermostat maintains minimum temperature. Not max. Get a higher rated unit. I didn't look at your pictures, just the comment about covering the radiator.
yes I know , and that is the problem it can not keep the minimun temperature , look like the thermostat is closing and opening all the time....but not when racing

I have no photos with the radiator cover fitted but it simply a carbon sheet with out any hole except the hoes for the light motors actuators on the cornners, nice look!
ill try to get one tomorrow
 
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josbeat

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comparing the 7mgte cooling system with the 2jz-gte system the differences are:
no coolant line from the back of the head to the thermostat housin like in the mk3 and the by-pass line is cotroled by the thermostat so when the thermostat is open the hot water throw the by-paas line is closed
the thermostat is after the radiator not before like in the mk3
so basicly the diference is in the 2jz-gte the water is pulled by the pump thru the block and only have one exit at the head, not two like in the 7mgte but the thermostat is at the back of the water pump with a two way system thermostat compared with the on way thermostat and all time or free flow by-pass lines on the 7mgte.

in my 7mgte I have three exit on the head going to the thermostat , no by-pass lines so nice for track use but horrible for all days use.
the solution will be .... conecting the by-pass line again but with a manual tap (open on a public road and closed inside the track) instaead bloking half radiator cooler with a plain of carbon plate which was my first idea jejeje