Mustang5L5’s progress thread - Boom

[FastDriver]

Or overfilled, and doesn't hit the pop-limit in cold weather. Also, these liquid lines today are often not to proper spec. They are often too restrictive. Confirmed this with a couple of folks who spend a LOT of time on foxes professionally.

I'm going to address this in Black Jack, where I have a measured pressure issue that looks like a clog, even when everything was brand new, and another airflow problem in the cab. I remember black jack's system being amazing. Now, it doesn't cover it in hot weather.

 

[Mustang5L5]

But 3-4 years later? It wasn’t even that warm when this happened. I’ve driven on 95+ humid days without issue. I think it was barely 80 when this happened. I also filled by weight, and pretty sure I stayed towards the low end

Liquid line was an NOS piece. I have a 2nd NOS unit as well.

Maybe I’ll address it later this summer. I did some more driving and tuning today. Working on my startup from cold start( well 80 degrees) to hot restart. Also did some more driving and pulling fuel out of the top end of the VE table. It’s getting there. As you can imagine lots of adjustment to the top end being made.

Car drives pretty nice. Still a bit rough around the edges but it’s getting there.

 

[85GTStangGuy]

....Need to source a new blowoff valve....

This it??

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[FastDriver]

Awesome. Yeah, those are valid reasons to doubt my guesses. Glad the tuning is getting there. Wish I had a NOS liquid line.

 

[WhiteCobra95]

How does the A/C on these cars work? Is the pressure mechanically regulated or does the ECU cycle the compressor from a high pressure sensor? I've never had to work with these systems but it would be good to know. Any overview you can provide would be great. I've worked on modern cars with both variable compressors and cycling systems, but I don't know how they did it with EEC-IVs.

 

[Mustang5L5]

There is no high pressure switch. It’s a mechanical relief valve. When you get over 450psi it just vents.


However looks like the relieve is not a one-time use thing if I’m holding pressure. Need to get my gauges on it and see how much exactly

 

[FastDriver]

Definitely not one time use.

 

[Mustang5L5]

Well just to update. No pics

Been working on the tune. Having the right injector settings has made this easier I will say. But cold start is pretty sweet now. I have cold and hot starts from 80-185degrees pretty dialed in. Can't really work on 20-80 degree starts til fall/winter. I'll never drive the car in the winter, but I do have reason to start up and move it once in a while so i need to make a note to work on the tune at those temps.

Been doing short drives with auto-tune. As i suspected with the wrong injector settings, the VE table was leaner than needed at low RPM, and much higher than needed at load/higher RPM. So been slowly tweaking that. Car is pretty nice to drive. Not really much else to say. It starts up, doesn't stall, idles nicely and drives pretty smooth. Still need to tune accel enrich a tad (bucking when i jump on the gas a bit) but can't really do that until the VE table is fully dialed in, which i'm not ready to claim yet.

In other news, finally tracked down a local rear hatch glass that might have a good read defrost grid. Mine was destroyed years ago and my OCD wants an intact grid as i hate looking back and seeing the lines torn up. So if it tests out good, i'll polish it up, have it tinted (along with rear quarter windows) and slap it on.

Haven't looked at the AC yet. I've been mostly driving in the evening when it cools off anyway so hasn't been a need. I'm contemplating changing this out for R-134a if i have to discharge the system, which I think i do. I have to get a vacuum tank, pull a hard vac and reclaim my R12. Or at least that's the story i'm telling people

 

[FastDriver]

In other news, finally tracked down a local rear hatch glass that might have a good read defrost grid. Mine was destroyed years ago and my OCD wants an intact grid as i hate looking back and seeing the lines torn up. So if it tests out good, i'll polish it up, have it tinted (along with rear quarter windows) and slap it on.

Haven't looked at the AC yet. I've been mostly driving in the evening when it cools off anyway so hasn't been a need. I'm contemplating changing this out for R-134a if i have to discharge the system, which I think i do. I have to get a vacuum tank, pull a hard vac and reclaim my R12. Or at least that's the story i'm telling people

R12 was awesome. I miss it, but early on Black Jack did amazingly well with R-134 until I screwed things up trying to learn A/C.

After the pickup truck hit me and crumpled the hatch a bit, I took an insurance pay out and started looking for a replacement hatch, rather than straightening and/or paying for paint. I was so fortunate that the one I eventually found came off of a car with great tint and working defrost. Black Jack has literally never had working defrost until this hatch. As an added bonus, it came off of a late 91 car with the later hatch striker. Now, it clasps easily and has no bushings on any striker, anymore. I had to replace a few of those a year.

Glad you've got most of the tuning finally ironed out. I remember your injector settings being my biggest concern when you first started, but doing it a few times is a great way to cement the concepts and see what it looks like when things are off. I haven't spent enough time with idle in heat like this. Mine does fine when A/C is off, but surges in hot weather with A/C on. Once you learn how to tune, I wonder if you ever get to a point where you really feel like you're done. Hasn't happened to me, yet.