Archive for the ‘Build Process’ Category

Day Seventy-eight…

Sunday, August 10th, 2008


I figured out how to get the A/C working on the Miata. I had to do some soldering in two places and added a relay to control the A/C relay.

Now, the A/C works perfectly. Got cold air now. I’m not even using the ECU to control the A/C. The reason is that my engine has so much torque at idle that it doesn’t really drop in RPMs that much when the A/C compressor is running. I just had to increase the idle to about 850-900 RPMs then when the A/C compressor kicks in, then it drops to a nice galloping 750-800 RPMs. But, when I disable the A/C by the button on the dash, the engine revs up a bit more to 850-900 RPMs. Not too bad.

When winter comes around, I’ll just leave the A/C off and adjust the throttle accordingly. Even with the large cam that my engine has, even if it dropped down to 650 RPMs, it’d still gallop nicely with the A/C enabled. The reason why I increased it is for throttle response time. If the RPMs are too low, the engine responds slowly at acceleration.

I’ll be putting up pics of how the wiring goes in on the A/C switch behind the dash. The rest is straightforward. If the A/C button is enabled, the A/C clutch and fan both disable when in START mode (cranking) and activates once again when the engine’s started. You might want to add a relay to disable the whole circuit when the engine is off so the clutch and fan are not energized when in the RUN mode while the engine is off. That’s the next thing I’m going to do. But for the meantime, I’ll just keep the A/C button off when the engine is off. The whole circuit de-energizes when in ACC or OFF mode along with the entire blower fan/cooling/heating circuit as it should.


Day Seventy-seven

Thursday, August 7th, 2008

I picked up my Miata this morning and spoke to Steve at Arizona Auto Air and he was talking about the electrical system not being complete. Turns out that I need to rewire my fans so that one fan is hooked up to the engine temperature switch and the other fan connected to the air conditioning fan circuit.

Right now both fans are connected to the engine thermostat switch. I need to take one fan off that circuit and wire it into the air conditioning fan connector and go from there. I believe that once this circuit is complete, the compressor will come online. Steve expressed urgency in the fact that if the fan don’t turn on when the compressor turns on, there could be some severe repercussions in regards to the pressure regulation. That was just some fancy babble to say “boom”.

Pictures of the AC system to come shortly.

Day Seventy-six…

Wednesday, August 6th, 2008

I called Steve at Arizona Auto Air and inquired to see if the car is done. He, with pleasure, informed me that my car was completed and ready to go. I need to do some further electronic diagnostics to make sure everything works right. He stated that his business just hooks up the A/C, charges it, and makes sure everything generally works. But for anything past that, especially in my situation of a custom installation, they are limited to the A/C system and not the electronics that is involved.

So, I’m probably going to pick up the car tomorrow after work.

Day Seventy-five…

Thursday, July 31st, 2008

I took my Miata over to the Arizona Auto Air place of business to get my A/C system hooked up. The owner, Steve, was pretty eager to take on this project.

Turns out that the project is going to need a bit of re-arranging of how components are implemented. Like for example, the drier has to be located before the compressor instead of in front of the condenser. Steve said that he needed to put in an expansion valve before the input line to the evaporator.

I was fine with that. I basically told Steve to do whatever it takes to get it to work. I mean, it’s f’ing hot here in Arizona. I’d like to enjoy the car at the hottest time of the year…

Day Seventy-four…

Tuesday, July 29th, 2008

Good news!

My carbon fiber hood from Simpson Design arrived today! I was too eager and started ripping the box open so I could get it on the Miata. Oh gosh, it looks so nice. There’s something about how real carbon fiber looks as opposed to the faux crap.

Here are some pictures:

Update: By request by a few people for me to put up pictures of the underside of my hood.

The Simpson hood requires no fiddling with it. It bolts right up onto your Miata’s existing hood mounts. This is one very impressive piece of work. The workmanship is superior. The only requirement was to have it worked on by a fiberglass body shop and have them wet-sand at 600 grits to smoothen it out and paint it with a UV protective clear-coat.