A few overdue updates:
Well, I drove my car over 200 miles at the beginning of August, round trip to a family gathering, for the girlfriend.
Well, on the way there, I went to pass somebody on a two lane stretch , down shift, pull out to pass, just down shift and get into about 12 PSIG of boost, when *poompfff* all boost goes away, and the car lays down a little, still pulled, but not as hard as wehn there's boost. The Girlfriend is like "what was that?" I just looked at her and said, "It was just a coupling, just won't have boost." "Will we make it there?" she asked. "Yeah, no worries."
So we get there, I open the hood hoping that it's just the throttle body coupling, that would be easy to fix, since I had similar issues in a previous vehicle using the same TB, nope, that's not it, keep looking, nothing from the top, look under, sure enough it's the lowest coupling, directly under my oil pan, just in front of the trans. :facepalm:
So we visited for a bit, then eventually pulled my car down to the garage, jacked it up and re-installed the tube into the coupler. I decided to check the couplers near there, and tightened all of them under the car. I then decided to check all of the couplers from above, and sure enough all of them were loose. One in particular was odd, when I started tightening it, the coupler started to expand around the tube, which is not a normal thing to happen, when tightening the clamp. Sometimes, it may flare out just a tad, but not like this was. So I loosened the clamp off, slid it up and bit and tightened down the clamp, it actually tightened around the tube then. Didn't think a whole lot about it, other than I figured that could have been the cause for a sound I was hearing recently under boost. It was, the cause.
A little while later we leave, it's a gravel driveway, and road from the farm and out to the paved road. So I get out on the dirt road, get it in 2nd gear hit the gas a little and hit 5 PSIG, good, all fixed. Get down to the paved road, pull out, hit the gas, 1st gear, major boost, like 15 PSIG worth of boost, it's NEVER done that before, pull second gear, boom, another 15 PSIG reading on my gauge, hot damn, that's awesome! Get a little farther along in 4th gear, I see 20 PSIG on my gauge! I have max boost commanded as 18 PSIG, since I was trying to find a boost control problem previously, and commanded more than I wanted, just to meet target boost.
So now after tightening the clamps, and placing the one clamp properly, I now have SOLID boost in all gears, it's way too much fun when it hits these boost levels. I'm once again impressed by the L28. It seems I've had this leak for a while, since I couldn't get the variable boost (based on MPH) to work properly for a long time.
I took a friend of mine for a ride today, when he first got in the car, he knocked my emulator connection out, I have it in kind of a bad place with nothing to protect it. It pulled hard in limp home mode, only running on spring pressure, which produced about 12 PSIG. Plugged the emulator back in, and took him back the other way, for some reason boost was down a tad (He is a big guy, and could really feel that he was in the car), but 13 to 14 PSIG of boost in 5th gear is a lot of fun. Things get quite blurry.
He was thoroughly impressed with how the car performs.
So glad to finally have the boost control side sorted out. It spikes by about a PSIG, but I think that is due to too high of an initial wastegate duty cycle setting, again from trying to chase down the boost control issue previously.
Then a newer update:
Well, the I6 era for this car ended last night.
I've had a slight issue the last couple of weeks that when I would hit high boost and high RPM, it would seem like the ignition signal would go all wonky and act like I hit a fuel cut limiter. Tried changing a few things, lowered the boost level, as a temporary solution. Changed another part tonight, to try and solve the issue, went for a short drive to a local hang out spot, problem not solved, when I went to leave the engine turned about half a turn, stopped, then turned over normally, and started to run, only it ran like the fuel rail was heat soaked, but looking at the AFRs they were fine, then a cloud rolled past my window... Awww man...
It was white, and when I revved it a couple times water or coolant came out of the exhaust and landed on the asphalt.
Well that solves the mystery, headgasket.
So I dropped the car off at home, and went for a lap in my friend's car, came home, and pulled the plugs. #6 was wet, the rest were perfect.
Oh well, time for a new engine.
So I'll be selling off all of my I6 parts, anyone interested? That includes the turbo cam cover and turbo exhaust manifold, modified intake manifold, which is smoothed and modified for 14mm O-ring injectors, including the fuel rail.