LS1 swapped 89 IROC Vert running too cool
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LS1 swapped 89 IROC Vert running too cool
I found this thread but figured I would start a new one.
http://www.thirdgen.org/techboard/lt...ing-issue.html (Ls1 cooling issue?)
The swap is pretty much done. Sitting at idle the car will heat up to temp about 220 F turn the fans on and regulate temp like its suppose to. As soon as we drove it, pretty cool night, the temps went way down on the gauge. The thermostat and water pump are brand new, went in with the swap. The thermostat is made to the water neck. I took it out anyway last night and it was closed. Put it back together and filled her back up through the top radiator hose. Started the car with the rad cap off and kept filling until it would take no more, then put the cap back on. I verified the gauge on the dash while logging in HPtuners, the gauge is correct. We didn't get to drive it last night, but pretty sure everything is working like it should. Anybody else ever seen this?
Could it be that the thirdgen radiator is cooling to good? We have the heater core hooked straight to the water pump, no valves. Fan temps are stock 4th gen fbody settings.
It seems to me that the thermostat should regulate the temp no matter what. I am stumped.
http://www.thirdgen.org/techboard/lt...ing-issue.html (Ls1 cooling issue?)
The swap is pretty much done. Sitting at idle the car will heat up to temp about 220 F turn the fans on and regulate temp like its suppose to. As soon as we drove it, pretty cool night, the temps went way down on the gauge. The thermostat and water pump are brand new, went in with the swap. The thermostat is made to the water neck. I took it out anyway last night and it was closed. Put it back together and filled her back up through the top radiator hose. Started the car with the rad cap off and kept filling until it would take no more, then put the cap back on. I verified the gauge on the dash while logging in HPtuners, the gauge is correct. We didn't get to drive it last night, but pretty sure everything is working like it should. Anybody else ever seen this?
Could it be that the thirdgen radiator is cooling to good? We have the heater core hooked straight to the water pump, no valves. Fan temps are stock 4th gen fbody settings.
It seems to me that the thermostat should regulate the temp no matter what. I am stumped.
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After looking at the way the heater core is hooked up, could it be that the heater core is cooling the the car down while going down the road? Since it is hooked up behind the thermostat?
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The car regulates temp all day long sitting at idle. Stays at 220F. Temp only drops when you drive it.
Fans are connected to the PCM, just like stock. Stock Fbody temp settings. And they both work like they are suppose to.
eh thats a possibility, are your fans on a switch? or are they always on ?
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May try putting a valve in the heater core hose and see if that helps. These cars had a valve stock that blocked coolant off from going into the heater core when the selector on the dash was in the cool setting.
#11
sorry to steal your thread for a minute here but does this mean that me not running a thermostat and my engine temps staying between 170 - 185 during a sunny day and 160 - 170 at night is bad? normal operating temp is 220*, right?
engine: 2004 5.3 285lr 235/243 614/624 113 cam
engine: 2004 5.3 285lr 235/243 614/624 113 cam
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Actually, the LS1s are designed for constant flow through the heater hoses. Where a HCV is used (GTO) it a 4 port that allows circulation even when closed.
Any chance you have the wrong thermostat/housing for the pump? There are 3 styles at least. Sounds like yours could be possibly allowing it to leak through at high rpm?
Any chance you have the wrong thermostat/housing for the pump? There are 3 styles at least. Sounds like yours could be possibly allowing it to leak through at high rpm?
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Weird , 1 thing that comes to mind is those stupid hypertech t-stats , the kind that keep the temps down on purpose, are you positive that yours is stock? what kind of gauge are you running? well if hp tuners is showing it low also then i guess that rules out the gauge. I would swap out the t-stat just to make sure.
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Its and AC Delco water neck with the T stat made into it. Brand new from the dealer.
We bought a new stat from Autozone and it was the drop in style not made to the neck so we didnt swap it.
The one that is on the car has a small bypass hole to bleed air by but there is no way that is causing anything.
I did log the car the other night and the temps dropped to 190, in HPtuners. I know the thirdgen gauges are pretty crappy. The tack is way off. So maybe its not getting as cool as I think.
We bought a new stat from Autozone and it was the drop in style not made to the neck so we didnt swap it.
The one that is on the car has a small bypass hole to bleed air by but there is no way that is causing anything.
I did log the car the other night and the temps dropped to 190, in HPtuners. I know the thirdgen gauges are pretty crappy. The tack is way off. So maybe its not getting as cool as I think.
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Sounds likely in your case. Prob have a 192 degree stat?
All GM gauges suck. 195 is less than half way on my truck, got it up to 230 once and it pegged the gauge. WTF? Gauge starts at 100 degrees, but by the time it starts to move and hits the 100 mark its already about 130. Basically worthless.
All GM gauges suck. 195 is less than half way on my truck, got it up to 230 once and it pegged the gauge. WTF? Gauge starts at 100 degrees, but by the time it starts to move and hits the 100 mark its already about 130. Basically worthless.