another friggin A/C question

[bmadd2402]

ok. I know this question has been asked millions of times, but no one has yet give a straight answer. the closest anyone has come was wulfgang (as far as making sense). is there a way to make the A/C work on an s13 so all you have to do is press the A/C button and crank it up??? There are always smart a$$ comments, and pics of verts with crap hanging out of them, which is very cute by the way, but no straight answers. wulfgang makes it sound easy. I looked at the diagrams, and it makes sense. but I dont want to try it if someone else tried and knows it doesn't work. lets get some good info put out here, and please keep your smart comments out of this thread.

[Sky80]

The best solution that i have found would be http://www.hotrodair.com/pg1a.cfm they make a universal kit that you could hook up, use your existing controls(but replace all the other ac components) and it would work great on your RB powered car...

[bmadd2402]

too involved. If I could spend 800 bucks on my AC, I probably wouldnt have my 240sx. the components are there, its just a question of making them get a long.

[RB20DETodd]

from what i got, wire your existing a/c harness plug from the ka to the single black wire next to the clutch on the compressor, charge and woohoo, got to get custom a/c lines though, and check for power at the old a/c plug with the a/c button in and out. Also replace the reciver dryer, evacuate system .etc

[Wulfgang]

It's a little more involved than that, but not bad. In addition to splicing in the RB's A/C clutch plug, you have to move the two A/C control wires from the KA ECU to the RB ECU.

The S13 works the same way as the S14. The only difference is that the S14 has a triple pressure switch while the S13 has a dual pressure switch. The 3rd switch on the S14 is used to control the auxilliary fan, which is unneccessary on the S13 because the fans are independently controlled. As with just about everything else, the S13 is quite a bit simpler and more straightforward than the S14.

IMHO the best system you can do is the one Nissan already set up for you. I did this on the S14, using the KA compressor with a custom bracket on the RB20 (with extended KA suction line and shortened KA discharge line). I bought a new dryer, cleaned out the whole system, replaced the compressor oil with mineral oil (much better than PAG or ester oils), and used Duracool refrigerant (better than R12). The new system works well and uses about half the horsepower of the equivalent R-134a system while cooling better. It is also very, very quiet. I think that is partly due to the reduced compressor load and partly due to the mineral oil.

So A/C is doable, but like in the other thread going right now, make very sure you have good ducting. Most people don't have the splash guard installed. Get it on.

[RB20DETodd]

It's a little more involved than that, but not bad. In addition to splicing in the RB's A/C clutch plug, you have to move the two A/C control wires from the KA ECU to the RB ECU.

The S13 works the same way as the S14. The only difference is that the S14 has a triple pressure switch while the S13 has a dual pressure switch. The 3rd switch on the S14 is used to control the auxilliary fan, which is unneccessary on the S13 because the fans are independently controlled. As with just about everything else, the S13 is quite a bit simpler and more straightforward than the S14.

IMHO the best system you can do is the one Nissan already set up for you. I did this on the S14, using the KA compressor with a custom bracket on the RB20 (with extended KA suction line and shortened KA discharge line). I bought a new dryer, cleaned out the whole system, replaced the compressor oil with mineral oil (much better than PAG or ester oils), and used Duracool refrigerant (better than R12). The new system works well and uses about half the horsepower of the equivalent R-134a system while cooling better. It is also very, very quiet. I think that is partly due to the reduced compressor load and partly due to the mineral oil.

So A/C is doable, but like in the other thread going right now, make very sure you have good ducting. Most people don't have the splash guard installed. Get it on.

Thanks wulfgang for the added info, do you know where these wires for the ecu are at? and what to splice?

thanks

[Wulfgang]

Sorry, but I no longer have the S13 FSM. But once you find the 2 wires, you can use my RB20 into S14 wiring guide for the RB20 side of things.

[RB20DETodd]

Sorry, but I no longer have the S13 FSM. But once you find the 2 wires, you can use my RB20 into S14 wiring guide for the RB20 side of things.

Cool sounds good, im thinking of bypassing the ecu totaly, for some reason im not getting power at the old a/c plug, so what i was gonna do is wire the pressure switch into my power wire to the compressor, from what i found out is that the pressure switch on the reciver dryer is a 3 position switch, 0, pressure is normaly open, and with a charge in the system it goes to normaly closed then at danger psi it goes normaly open again, turning off the a/c, that would be my saftey device.

[FAST-DATSUN]

all/most all the electircal on the S13 is in the chassis wiring. You need to use your compressor or build new lines for the JDM compressor, have it charged and your in.....S14 is much harder...............do to the different operation systems of the JDM and US computer...

[RB20DETodd]

all/most all the electircal on the S13 is in the chassis wiring. You need to use your compressor or build new lines for the JDM compressor, have it charged and your in.....S14 is much harder...............do to the different operation systems of the JDM and US computer...

I just tested my reciver dryer pressure switch and it is normaly open with 0 press and closed with a system charge and open with a over pressure woohoo! Just waiting on my bigger fans and then time for the a/c, i have custom lines to the rb compressor.