Overheat when under boost
#1
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Overheat when under boost
When i run on the freeway around 75mph on a 60-70 degree day it begins to heat up rapidly, but under 70 is all right and cools it right back off. any ideas?
Ps on a 75-80+ degree day its around 65mph.
Ps on a 75-80+ degree day its around 65mph.
#3
I had the same problem, only when the AC was on. Turned out the relay was bad and the AC fan wasn't working. I'd check the fans to make sure they come on. You also want to make sure you have the undertray on, that's is pretty much going to eliminate the pressure differential across the radiator at speed which would cause it to overheat.
#11
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I had the same problem, only when the AC was on. Turned out the relay was bad and the AC fan wasn't working. I'd check the fans to make sure they come on. You also want to make sure you have the undertray on, that's is pretty much going to eliminate the pressure differential across the radiator at speed which would cause it to overheat.
#12
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that doesnt have to happen to have a blown head gasket. coolant could be leaking directly into the combustion chamber, without any loss of oil.
exploding gas and oxygen is pretty damn hot.
but your issue doesn't sound like this is the case, it would also idle like crap.
whats your cooling system like? stock? undertray removed? intercooler? whens the last time you checked your coolant levels?
exploding gas and oxygen is pretty damn hot.
but your issue doesn't sound like this is the case, it would also idle like crap.
whats your cooling system like? stock? undertray removed? intercooler? whens the last time you checked your coolant levels?
#13
Just having the under tray doesn't always do it. My car has a 3" thick ic as big as the "mouth" with ac behind that then a thick rad, while the under tray helps so does a reroute and the most helpful was the larger rad so far. I think the biggest help for me will be "mouth ducting" as mine is poor / non existent and the airflow goes out the wheel wells. My iat deltas are 1-2C so there must be some flow.
You'll need both fans wired together. I am fine temp wise until I go over 110-115kph, over 120kph (~75mph) my heat sits at 102C from the normal 93-97C.
You'll need both fans wired together. I am fine temp wise until I go over 110-115kph, over 120kph (~75mph) my heat sits at 102C from the normal 93-97C.
#15
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you shouldnt need fans at all just driving around. fans should only be coming on when you're stopped.
I have a smaller all aluminum radiator, and it's uncommon for the fan (singular) to come on. I average 185-187°F coolant temps. If I sit in traffic they can come up to 200°F where my stock fan comes on and the temps quickly drop back to 190°F where the fan shuts off and the cycle continues. If I start to drive again, temps drop back down to 185-187°F. If I do boosted pulls (fan disabled over 75% TPS) the temps will increase, but it's nothing that the fan and overall MPHs can't handle.
If you need dual fans in this situation, it seems to me that your cooling system is not up to snuff.
I have a smaller all aluminum radiator, and it's uncommon for the fan (singular) to come on. I average 185-187°F coolant temps. If I sit in traffic they can come up to 200°F where my stock fan comes on and the temps quickly drop back to 190°F where the fan shuts off and the cycle continues. If I start to drive again, temps drop back down to 185-187°F. If I do boosted pulls (fan disabled over 75% TPS) the temps will increase, but it's nothing that the fan and overall MPHs can't handle.
If you need dual fans in this situation, it seems to me that your cooling system is not up to snuff.
#16
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get high pressure water hose with 1/4" ID
get schrader valve to 1/4" barb fitting
stick hose on fitting and other end on overflow nipple
remove radiator cap and place something in the hole that allows the LARGE OD seal to seat and the smaller one NOT to seat. A bent paperclip will work.
replace radiator cap
pump up cooling system with bike pump. it should hold 20 psi almost indefinitely.
get schrader valve to 1/4" barb fitting
stick hose on fitting and other end on overflow nipple
remove radiator cap and place something in the hole that allows the LARGE OD seal to seat and the smaller one NOT to seat. A bent paperclip will work.
replace radiator cap
pump up cooling system with bike pump. it should hold 20 psi almost indefinitely.
#18
There is no way the fans should be on when driving. Fans move less air than driving at 30. Ive been testing cooling( see the humongous duct thread in race prep) and lately ive been running no fans at all. With only ducting installed. And only in front of the radiator with no vents in bonnet, running a stock radiator, i overheAt under jogging pace and i can redline it through the gears and when it gets to 100mph its cool again. Retarded timing increases exhaust temp not engine temp.
#20
There is no way the fans should be on when driving. Fans move less air than driving at 30. Ive been testing cooling( see the humongous duct thread in race prep) and lately ive been running no fans at all. With only ducting installed. And only in front of the radiator with no vents in bonnet, running a stock radiator, i overheAt under jogging pace and i can redline it through the gears and when it gets to 100mph its cool again. Retarded timing increases exhaust temp not engine temp.