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Madd Tyte JDM yo ®
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Discussion Starter · #1 ·
Im Going to be installing my Contour dual electric fans. There are only 2 wire hook-ups on it, + and -. i know i can simply splice the dual AC puller fan harnesses together so i can pull twice the current. There is no need to add aftermarket wiring or pull power from the fuse block or add a thermostatic switch.

The operation of the Pull-type/suction fan motors:
When the ignition switch is turned on the current flowing to the guage fuse flows to terminal 2 of the condenser fan relay -> Terminal 4 -> Terminal 1 of A/C high pressure switch -> Ground, energizing the condenser fan relay. Thus causing current to flow to terminal 1 of the relay flows to terminal 3 -> Terminal 2 of the condenser fan motor -> terminal 1 -> Ground, causing the motor to rotate. This occurs when the refrigerant pressure exceeds 220psi with the A/C high pressure sw on, or when the water temp is 100*C (212*F) or more with the A/C water temp sw no. 2 on.
When the refrigerant pressure is 178psi or less with the A/C high pressure switch off or the water temp is 95*F (203*F) or less with the water temp SW off, the motor does not rotate.


So, even with no pressure in my AC system, my AC fan wiring will be energize when my coolant temp hits 100*C. unfortunately, thats about 10* hotter than im comfortable with. id like my AC water temp sw no. 2 to close the circuit at a lower temperature.

anyone have any idea if toyota had an AC water temp switch that closes at about 202*-204*F? then i could just swap them out on my water neck, retain the factory relability of the relay/failsafe system and have my bad-ass fans work like toyota intended.
 

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Supras Invade Las Vegas
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Being in Florida you "might" get away with the elect fan. The rest of us actually have to drive up hills. :)

I would suggest that you skip the elect fans unless your cooling system is working 300% perfectly.

My cooling system works pretty damned good - 185K miles on the original motor and more than 20,000 of those are on the road to Vegas with some pretty extreme driving conditions. From the day I purchased my 89T my temp needle never moved - even sitting in rush hour traffic with the AC on full.

Only when I went to an electric setup did I see any movement.

There are far safer and better ways to recover those 5hp (est) that an electric fan will get you. I've read too many horror stories about the electic fans to even consider making this change again.
 

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flubyux2 said:
Im Going to be installing my Contour dual electric fans. There are only 2 wire hook-ups on it, + and -. i know i can simply splice the dual AC puller fan harnesses together so i can pull twice the current. There is no need to add aftermarket wiring or pull power from the fuse block or add a thermostatic switch.

The operation of the Pull-type/suction fan motors:
When the ignition switch is turned on the current flowing to the guage fuse flows to terminal 2 of the condenser fan relay -> Terminal 4 -> Terminal 1 of A/C high pressure switch -> Ground, energizing the condenser fan relay. Thus causing current to flow to terminal 1 of the relay flows to terminal 3 -> Terminal 2 of the condenser fan motor -> terminal 1 -> Ground, causing the motor to rotate. This occurs when the refrigerant pressure exceeds 220psi with the A/C high pressure sw on, or when the water temp is 100*C (212*F) or more with the A/C water temp sw no. 2 on.
When the refrigerant pressure is 178psi or less with the A/C high pressure switch off or the water temp is 95*F (203*F) or less with the water temp SW off, the motor does not rotate.


So, even with no pressure in my AC system, my AC fan wiring will be energize when my coolant temp hits 100*C. unfortunately, thats about 10* hotter than im comfortable with. id like my AC water temp sw no. 2 to close the circuit at a lower temperature.

anyone have any idea if toyota had an AC water temp switch that closes at about 202*-204*F? then i could just swap them out on my water neck, retain the factory relability of the relay/failsafe system and have my bad-ass fans work like toyota intended.
ya, i tried wiring it to the stoc a/c fans, worked like shit.
I just have my contour fans hardwired now.
But i'm going back to stock for peace of mind.

The way i see it, is with the electric fans, if it burns out or melts a wire etc far from my house, i'm stuck.
I'd rather just keep the stock, it will cool good enough
 

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Madd Tyte JDM yo ®
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Discussion Starter · #4 ·
well, if i can find a thermostatic switch that turns on at a lower temp, then itll have stock reliability and convenience. these are factory fans of a wrecked 97 contour. im not worried about contour fans not cooling enough. the integrated fan shroud on the dual fans will seal pretty well. i just dont want a clutch fan because it looks horrible, i hate the clutch fan noise, and i would hate for the clutch to stick while im revving to 7500rpm.

btw, there are 1200hp mkivs running stock radiators and water pumps w/ electric fans... i think ill be ok w/ 800rwhp on my setup. i just want to have the switch turn on at a lower temp.

i understand what you guys are saying about the electric fans failing or whatever... ive seen aftermarket fans and thermostatic switches fail. tahts why im trying to use factory quality parts... so it should be able to last for years and years with tens of thousands of miles of use.
 

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i've never really heard a mk3 clutch fan sticking when reving to 7500rpm. But then again, not too many mk3's reving that i personally know of.

But i wish you the best in your hunt.
 

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Madd Tyte JDM yo ®
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Discussion Starter · #6 ·
thanks man... maybe ill just install an aftermarket adjustable thermostatic switch and wire it into the stock AC temp theromoswitch harness. so the signal will be sent by the aftermarket unit into the stock wire harness... as far as the car knows, its turning on at 100*C, when the new unit is actually turning it on at ~198*F... start the cooling a little earlier. ;)

i dont know if the stock clutch fan will stick DUE to the high revving, but i think that a clutch fan that is starting to stick may cause problems later on if it happens to stick while im at high rpm.
 

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92 TURBO
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flubyux2 said:
...........

The operation of the Pull-type/suction fan motors:
When the ignition switch is turned on the current flowing to the guage fuse flows to terminal 2 of the condenser fan relay -> Terminal 4 -> Terminal 1 of A/C high pressure switch -> Ground, energizing the condenser fan relay. Thus causing current to flow to terminal 1 of the relay flows to terminal 3 -> Terminal 2 of the condenser fan motor -> terminal 1 -> Ground, causing the motor to rotate. This occurs when the refrigerant pressure exceeds 220psi with the A/C high pressure sw on, or when the water temp is 100*C (212*F) or more with the A/C water temp sw no. 2 on.
When the refrigerant pressure is 178psi or less with the A/C high pressure switch off or the water temp is 95*F (203*F) or less with the water temp SW off, the motor does not rotate.


So, even with no pressure in my AC system, my AC fan wiring will be energize when my coolant temp hits 100*C. unfortunately, thats about 10* hotter than im comfortable with. id like my AC water temp sw no. 2 to close the circuit at a lower temperature.

anyone have any idea if toyota had an AC water temp switch that closes at about 202*-204*F? then i could just swap them out on my water neck, retain the factory relability of the relay/failsafe system and have my bad-ass fans work like toyota intended.
^ 212 F is the maximum ON temp. of the switch and that is the temp. at the hottest sensing point on the engine, top of engine right out to your radiator. If you tested a few of these Toyota switches, I'll know you'll find one that closes around 205F.
You could get one for an Integra w/ A/C that closes at 194F (191-197 spec.) and opens at 185F. It's threaded like our stock one BUT the connector will be different. Cut the 2 wires & connector from a junked one. Also, an oil temp. sensor switch from a 95 Legend closes at 198F (192-203 spec.) and opens at 175F which is the one I threaded into the pass. side of my oil pan to turn on the relay for the electric pump for my oil cooler modification on my 92t.

Mike
 

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Madd Tyte JDM yo ®
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Discussion Starter · #8 ·
thanks for the input mike. thats a great help. ive got a butt-load of honda kids in my town, so ONE Of these jabroni's has to have a switch off a Teg.

i know the bung on the side of the oil pan is 12mm x 1.25 pitch, but i dont think tahts what the thread dia/pitch is on our stock ac temp switch. do you have any oil temps vs. observed coolant temps? id be curious to know how hot the oil is in relation to the coolant at any given time.

btw, what oil cooler did you set up on your 92 car?

thanks
chris
 

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92 TURBO
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^ I'm using the stock oil cooler with this 12 volt 2 gpm pump that's rated for oil temps up to 240F :
http://www.pegasusautoracing.com/productdetails.asp?RecId=156

I had a 16mm tapped plate welded in my oil pan on the pass. side along with a 1/2" tapped plate near the oil drain plug for oil out to the pump's intake, out of pump thru stock cooler and back into the stock return fitting on the pass. side of the pan. I'm thinking of adding a remote oil filter set-up in the line after the cooler and before the pan's return.
The oil temp switch I used is for a 95 Legend. I installed it in the new 16 mm hole with a copper crush washer and a friend of mine who works at a junk yard got me the 2 wire connector plug with wires from a Legend. The switch closes at approx. 195F which takes about 15-20 minutes of driving. This provides the negative feed to the coil of an added relay along with a 3rd possible negative feed to the stock relay for the 2 electric condenser fans. The relay's contact closes which turns on the pump and the 2 fans to provide for cooling air thru the stock cooler. I also added a time delay on break module to the circuit which allows the fans and pump to run for up to 10 minutes if needed with the engine & ignition off to cool down the oil. It works well as it does cycles on & off while driving as I have added a green light that tells me when it's on.
BTW, I don't think oil temp. goes too much higher than coolant temp. I'm holding mine between 175-195F
Mike
 

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Madd Tyte JDM yo ®
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Discussion Starter · #10 ·
Hey mike, thats quite an elaborate setup youve got there. i like how your oil cooler setup doesnt pose an impedance to the oil delivery to the rest of the block. did you not want to put a metric-to-AN adaptor on the drain plug of the pan because youd idnt want to have to remove the line for every oil change? what might be cool is to convert the drain plug to -8 or -10 and then have a ball-valve on a Tee right after the pump... so you could pump out the pan for oil changes with the greatest of ease ;) i might go along w/ that filter idea for the oil cooler setup... i would probably put it BEFORE the pump if its possible. is your pump rated for suction? ive never thought about plumbing a filter before an electric pump. the check valve in the filters might create a good deal of restriction on the suction side.

my friend has a coolant temp switch off his 96 D16 single cam civic motor. he said itd be the same as the integra AC switch. i guess ill see how that works out. ill extend the harnesses from the stock AC fans to my contour fans... its only 2 wires on the contour setup.

i still have to figure out how im going to mount my FC oil cooler... you think i should do a v mount w/ the fc cooler mounted horizontally in front of the lower end tank? im not sure which would get better airflow; horizontally w/ a scoop facing forward (Grand national style) or reverse, to pull air thru the V-mount orientation.
 

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92 TURBO
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flubyux2 said:
Hey mike, ....... did you not want to put a metric-to-AN adaptor on the drain plug of the pan because youd idnt want to have to remove the line for every oil change?

^EXACTLY, I had the pan off anyway so I figured it would better to make a new hole in the pan on the same side as the drain plug but a litlle higher up for the oil out to the pumps suction side. I installed a small ball valve right after the 90 elbow just incase I developed a leak on the road.

...... i might go along w/ that filter idea for the oil cooler setup... i would probably put it BEFORE the pump if its possible. is your pump rated for suction?

^ I thought of installing it before the pump to protect the pump BUT it's harder to suck thru an oil filter than to push pressure thru it. This pump will develop a maximum pressure of 60 psi @1.3 gpm with 10 psi @ 2 gpm. I wanted the gpms. I figure I'm circulating all the oil in the pan every 30- 45 seconds. Also the spec sheet that came with the pump says it can handle small " foreign objects" because it's a diaphragm type with 2 pistons. It's rated for constant fluid temps. up to 265F plus it's self priming up to 8 ft vertical height. It really moved gpm when I used it to pump all the old gas out of my tank after I finished my complete engine, brake/suspension rebuild. < 14 months in the garage up on stands. I also used the pump to flush out my stock oil cooler and lines with mineral spirits before re-mounting it.

..... never thought about plumbing a filter before an electric pump. the check valve in the filters might create a good deal of restriction on the suction side.

^ That's what I thought too! I figured it would lower my gpm.

my friend has a coolant temp switch off his 96 D16 single cam civic motor. he said itd be the same as the integra AC switch. i guess ill see how that works out. ill extend the harnesses from the stock AC fans to my contour fans... its only 2 wires on the contour setup.

i still have to figure out how im going to mount my FC oil cooler... you think i should do a v mount w/ the fc cooler mounted horizontally in front of the lower end tank? im not sure which would get better airflow; horizontally w/ a scoop facing forward (Grand national style) or reverse, to pull air thru the V-mount orientation.
^ I do it horizontally w/scoop.
Just my 2 cents
 

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Madd Tyte JDM yo ®
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Discussion Starter · #12 ·
horizontally, v-mount style... with scoop facing forward like a GN to pull air thru the cooler and then thru the IC, or facing backwards to pull air away from the high pressure area in the V of the IC and cooler? maybe GN-style facing forward would be better, eh? add more air pressure between the IC and cooler to "force" air thru the IC.
 

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Madd Tyte JDM yo ®
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Discussion Starter · #13 ·
hey, just a quick update... i grabbed a D-series coolant temp switch and the threads are TOO big of a diameter to fit in the stock toyota AC no.2 switch hole. so either the D-series and B-series switches are different... or the B-series integra switch doesnt fit either.

but, my oil cooler is also installed, V-mount style. i think right now, itll catch the air between the fmic and the cooler and go down and under the car since that should be a lower pressuer area under the car than in the mouth of the V-mount.
 
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