We're having an unusually cold spring, so of course I'm thinking about how to fix my A/C. But really...it's gonna be hot before yah know it. Using the Microsquirt left me with no way to pass through the A/C signal like the OEM ECU does. The A/C System can be completely self regulating and doesn't really need the ECU to intervene in any case. So this is what I went with...
Here's the stock arrangement. Essentially, the Thermo control amplifier is a thermostat which allows or disallows a signal to the ECU depending on the temperature at the evaporator. If it gets too cold, it interrupts the signal and the ECU opens the ground to the A/C Relay. My original thought was to use the output of this thermo amp to control a relay, however I was not getting the signal I expected out of the controller. So I had to abandon that plan...
So I just needed something to control the signal based on the evaporator temperature. Enter this $12 device...
And here's how I wired it up...
If you remove the glove box you'll see the thermo control amplifier mounted on the blower box. It's the little black box on the top left here, with the brown connector...
And here's where the evaporator sits, relative to the blower box...(my spare from my coupe, as an example...)
So, I loosened the two screws there on the blower box, pried it open a bit, and shoved the thermo-couple from the new controller in front of the evaporator. The location probably isn't suuuuper critical here...I don't think...I can adjust the temperature set-point on the controller, so if its measuring a little warmer than directly in front of the coil...no big deal - We'll account for it.
Wired everything else up and stuck the board to the blower box with some good double sided tape and...Voila. It works.
Currently, I have the target temperature set to 9deg C with a 2 degree hysteresis. Now...I just need to figure out how to scale the signal down so I can send it to the Microsquirt for Idle-up compensation.
So I fiddled around with the AC Idle up features on the Microsquirt. Since Megasquirt documentation is atrocious this wasn't immediately clear...but I can use the Micro to trigger the AC relay using one of the ALED or WLED outputs. And since I'm only using one radiator fan, this should work. The benefit being, the ECU can initiate the idle up (open the IAC more) before the AC relay closes, so this should prevent a dip in RPM.
It works. Megasquirt is so stupid. I assumed the "AC Idle Up Output" was the output for the idle control channel to yah know..."idle up" the engine during AC control. The channel should be called AC relay output or something else. And of course all the documentation is shit and vague. Anyway! It works. Still needs some tuning...but these are the settings I used...
Sucks about the engine probs.. +1 here on the feels of DD'ing your project. For almost a year I was anxiously driving my car down the road constantly thinking of, "if this does this then I'll do that" or "what's that sound/smell/vibration". Helps a heap to have 200 mile towing radius on the road side policy though!!
Great work with the megasquirt though all of it is way over my head haha..
Hope a new wind blows and helps rejuvenate your love in working with something that always seems to break or cause us heartburn..
Over this past weekend I swapped out my winter tires and got my new suspension setup on. I've been waiting and waiting for the weather to turn the corner, so i'm stoked I was finally able to get this all together.
Install was a breeze. The car seems to have survived the winter with hardly any rust detectable on suspension components. Still very, very clean. 4 hours total install time including bleeding brakes.
Pretty big difference between the free length on the front springs.
New goodness...Red springs on red struts on red car.
My impression of the appearance...I love the stance. It's not super low, and it looks very purposeful, especially with the aggressive tires. The 3/8 spacers have things pretty even front to rear. I should probable measure it to confirm...but I suspect the rear is still a hair lower. Anyway, here's a before and after comparison...
I went for a drive an man...Obviously it was quite a big change from 130K mile stock L suspension. I started with the struts on 2/6 front / rear. It felt super good on a few lower speed corners. I ended up bumping the front struts to 3 and left the rears on 6. The springs feel relatively stiff, however the ride is not as bad as I thought they might be. I don't much mind a stiffly sprung car - My old STI on RCE yellows was very aggressive and bouncy. This suspension seems a bit better controlled and should be easily tolerable for daily duty. More time behind the wheel will be require to really get a feel for the new balance and grip.
Saturday was my first autocross post-swap...and with the new suspension and tires...The car felt really good. I also modified my number's since I'm not in H-Street anymore.
The bump into SM is a little tough. It's very easy to be out-gunned in that class - I was up against a number of heavily modified cars, including a 400+HP half caged WRX and fully prepared E46 M3 with aero and enormous tires. It would end up that out of 7 cars in class, those were the only two that went faster so that feels good! I also went 9th fastest overall out of 76 entries - so not bad! Ton's of fun...
Here's roughly half a run...It went between two lot's at a community college.
A bit of body roll or weight transfer isn’t necessarily a bad thing at Autocross, especially if it’s a dirty surface. I do however think that these Tanabe springs are a touch too soft. They’re a good spirited daily spring and they weren’t bad at Autocross either, but it does feel a bit soft at times. I also could have gone up on the dampers, however I wanted to concentrate on driving more than fiddling with settings.
Stock front sway bar, 20mm rear. I could probably use a stiff front sway bar just to keep the inside front tire more planted on corner exit...might help a bit with forward traction.
A few more photos taken by a Local Subie group member...
I’ve been collecting parts to complete a rear disc conversion. One of my buddies gave me a pair of hubs but I needed discs and calipers. Someone on our local Facebook Subaru group was selling a full set of WRX rotors and pads with 4400 miles and rebuilt/painted calipers, so I picked the lot of up for $120.
The front rotors are about 1.25” larger than stock. Should be a decent upgrade.
Also picked up Stoptech stainless lines and new parking brake shoes/hardware to complete the job.
Front before and after:
The rear came apart pretty well. Arizona car level of corrosion isn’t fair. The Jesus bolts just came right out. I had to cut them off the donor hubs.
Also installed new parking brake cables for the conversion. Replacing these turned out to be one of the more annoying parts of the conversion.
Parking brakes assembled...
Rotor, caliper, bracket, line all installed...voila. Disc brakes.
Finished it off with Motul RBF600 DOT4 fluid.
First impressions are...well, it’s an enormous change from the stock brakes, especially with the SS lines. The feel is all together different, but the stopping power is obviously vastly better. The stock L brakes aren’t exactly well paired for a swapped car, and it legitimately felt dangerous at times. This is much better. For a budget upgrade, I’m stoked.
i've got the same setup with the WRX stuff and the Stoptech lines. GREAT setup. especially for such light cars. the biggest difference to me was in the MC brace. try one out. you'll be pleasantly surprised.