as always, posting clear detailed pictures of any custom mods, you do to any of your cars, from several perspective angles , along with a detailed description of what you were trying to accomplish and the theory behind any mods being done would be VERY WELCOME!
85 and 87a -> Ground
86 -> Power
30 -> Output
-30 = constant [positive (+)] power (usually wired directly to car battery)
-85 = coil ground (wired to the negative (-) battery terminal or any grounded metal panel in the car)
-86 = coil power (wired to the control source. could be a switch, or it could be the car's IGN or ACC circuit.)
-87 = switched [positive (+)] power output. (when the relay coil is powered, lead/pin 87 is connected to lead/pin 30)
-87a = [on 5 lead/pin relays only] this lead/pin is connected to lead/pin 30 when the coil is NOT powered.
BTW most early TPI corvettes had an oil cooler mounted between the engine block and oil filter that would reduce the oil temps in the engine, by circulating the engine coolant and oil thru separate,parallel passages , this had the advantage of more rapidly warming cold oil but keeping its max temp lower than without its use.
yes they work, they easily drop the oil temps 15 plus degrees F or more, by running the oil flow alongside but separated from the engine coolant. now they are NOT as effective as a aux cooler because they can,t lower temps to quite as low as engine coolant temp levels,and if you pay attention to your gauges youll generally see oil temps tend to run 15-30 degrees over coolant temps, on most engines. while if you install the AUX oil or trans fluid coolers , with the electric fans ,those can, at least in theory lower temps to outside air temps, or at least to significantly lower levels than the coolant temps. and yes that can easily be 100F LOWER. I,d also point out that a 7-8 quart baffled oil pan, the longer length oil filters and an adding an fan cooled oil cooler can reduce oil temps very rapidly , so get a few gauges installed to help verify actually operating oil temps.
http://www.griffinrad.com/load_details3.php?
PartID=441&year=1987&make=Chevrolet&model=Corvette
http://garage.grumpysperformance.co...fo-and-derale-trans-cool-pans.662/#post-89196
http://garage.grumpysperformance.com/index.php?threads/transmission-over-temp.12832/#post-78277
http://garage.grumpysperformance.co...ion-remote-filter-flow-rate.14621/#post-78250
http://garage.grumpysperformance.co...flow-rates-and-heat-transfer.9880/#post-64431
http://garage.grumpysperformance.co...n-cooler-info-and-derale-trans-cool-pans.662/
keep in mind that oil flow helps cool the engine, and having both a 7-8 quart baffled oil pan and a oil cooler with an electrical fan can significantly reduce oil temps and as a result the engine operational temps, thus lowering the heat loads on the radiator
85 and 87a -> Ground
86 -> Power
30 -> Output
-30 = constant [positive (+)] power (usually wired directly to car battery)
-85 = coil ground (wired to the negative (-) battery terminal or any grounded metal panel in the car)
-86 = coil power (wired to the control source. could be a switch, or it could be the car's IGN or ACC circuit.)
-87 = switched [positive (+)] power output. (when the relay coil is powered, lead/pin 87 is connected to lead/pin 30)
-87a = [on 5 lead/pin relays only] this lead/pin is connected to lead/pin 30 when the coil is NOT powered.
RRVETTE said:The CTS (coolant temp sensor) is located in the front of the intake manifold on the 84-91 C4's. It has two wires (yellow and black). The yellow wire might have a black stripe, it's been awhile since I looked.
84-85: The aux fan (if equpped) switch is located in the passenger side head between #6 and #8 spark plugs. It has a single green wire. If the aux fan is not equipped, the hole where the switch is will be plugged.
84-85: The coolant temp sender for the dash gauge or (IP) is located in the driver side head.between #1 and #3 spark plugs. It sends resistance signals to the dash gauge where the digital coolant display is.
86-89: The aux fan (if equipped) switch is located in the driver side head between #1 and !3 spark plugs. Single green wire.
86-91: The coolant temp sender for the dash gauge or (IP) is located in the passender side head between #6 and #8 spark plugs. It sends resistance signals to the dash gauge where the digital coolant display is.
90-91: Do not have a aux fan. They have two fans side by side..same as the 92-96. Both are controlled by the (90-92 ECM) or (94-96 PCM).
92-96: The CTS for the ECM or PCM is located in the water pump housing. This sensor sends signal to the ECM and the digital readout on the dash gauge.
Someone can correct me if wrong, but I believe the coolant temp sending unit for the analog guage is located in the driverside head between #5 and #7 spark plugs.
BTW most early TPI corvettes had an oil cooler mounted between the engine block and oil filter that would reduce the oil temps in the engine, by circulating the engine coolant and oil thru separate,parallel passages , this had the advantage of more rapidly warming cold oil but keeping its max temp lower than without its use.
yes they work, they easily drop the oil temps 15 plus degrees F or more, by running the oil flow alongside but separated from the engine coolant. now they are NOT as effective as a aux cooler because they can,t lower temps to quite as low as engine coolant temp levels,and if you pay attention to your gauges youll generally see oil temps tend to run 15-30 degrees over coolant temps, on most engines. while if you install the AUX oil or trans fluid coolers , with the electric fans ,those can, at least in theory lower temps to outside air temps, or at least to significantly lower levels than the coolant temps. and yes that can easily be 100F LOWER. I,d also point out that a 7-8 quart baffled oil pan, the longer length oil filters and an adding an fan cooled oil cooler can reduce oil temps very rapidly , so get a few gauges installed to help verify actually operating oil temps.
http://www.griffinrad.com/load_details3.php?
PartID=441&year=1987&make=Chevrolet&model=Corvette
http://garage.grumpysperformance.co...fo-and-derale-trans-cool-pans.662/#post-89196
http://garage.grumpysperformance.com/index.php?threads/transmission-over-temp.12832/#post-78277
http://garage.grumpysperformance.co...ion-remote-filter-flow-rate.14621/#post-78250
http://garage.grumpysperformance.co...flow-rates-and-heat-transfer.9880/#post-64431
http://garage.grumpysperformance.co...n-cooler-info-and-derale-trans-cool-pans.662/
keep in mind that oil flow helps cool the engine, and having both a 7-8 quart baffled oil pan and a oil cooler with an electrical fan can significantly reduce oil temps and as a result the engine operational temps, thus lowering the heat loads on the radiator
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