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Nice job! Out of curiosity, how tall are you? At 6'0" I had to go without sliders to get enough headroom in my C5, and my wife is going to run some extra seat cushions to get positioned right.

Check out links 2 through 5 on this page for info about logging: http://www.romraider.com/RomRaider/IncompleteGuideToTuning Actually, I recommend the whole thing, but since you asked about logging... It was written for RomRaider users, so a few of the terms are different than what Cobb uses, but translating won't be hard. For example what RomRaider calls "Fine Learning Knock Correction" is what Cobb calls "Fine Knock Learn." About those logs: The first log shows more knock learning than I like to see. DAM is still 1.0 so it's not too bad, and there's a bit of noise in knock detection so I'd do a couple more pulls to see if that was random or repeatable. By default, fine learning will pull 1.4 degrees on each knock event, and then add 0.35 degrees at a time if the engine doesn't knock again in the same RPM/load area. It pull timing 3 times in two areas. The area where it pulled twice in the same range is the most suspect - if that happens repeatably, pull timing in that area (and smooth out nearby cells) until it only rarely pulls timing (at most once every 5 pulls through that same RPM/load area). Some notes on which columns to log / not log: AF Learning parameters change slowly enough that I never log them. I just look at them once a day or so to make sure they're not getting more than a few percent away from zero. Dynamic advance isn't useful. If you want those values (which you probably don't) you can look the up from your tune, based on RPM and load. Same with MAF voltage. If you want it you can look it up based on MAF g/s. (might not be exact due to compensations, but it'll be close enough) You'll want a wideband O2s sensor if you get further into this.

I'm pretty sure that was all just pieces of the lane-line dots.

https://giphy.com/gifs/free-shoes-while-skydiving-gdxDJB5OJd3IyJfd36

It'd be better to print the scoop vertically - rotate it back 90 degrees so the front faces up, then there won't be a need for support. I've been toying with the idea of printing something besides a scoop just to fill that spot since I've got a FMIC.

Start here: The start over so you can watch it get built:

It might be interesting to get a data log showing that stumble, with these parameters: RPM MAF Load(calculated) Final fueling base AFR (preferably wideband but the stock sensor is fine for cruise and better than nothing for WOT) Total ignition timing Fine learning knock correction Feedback knock correction Knock Sum I have a little theory that low ignition timing, caused by knock correction, is a big factor in stumble. It has been for me.

https://gfycat.com/distantincredibleeagle-pasha-petkuns

The ebay ad has photos of 2DIN installs with electronic climate control. In my 05, the climate control circuit board extends all the way up into the 2DIN opening, so you can't install a 2DIN stereo unless you're willing to cut the circuit board in half and jumper all of the connections between the two halves of the circuit board (like 20 or 30 if I remember right). Is the 08 different in that regard?

So this magician in Spain walks to the front of the stage and says... "Uno..." "Dos..." And then he disappeared, without a tres.

How to do track days in style.

Related question - does anyone make aftermarket wheel bearings for 4th-gen LGTs? SKF makes a nice upgrade for C5s, but I don't see anything with their "X-Tracker" branding for Subaru.

Cam duration and "valve events" (opening and closing of the intake and exhaust valves) are always measured in reference some particular amount of valve lift. In the Subaru world, 0.006 inches is usually the reference, for example the stock intake cam duration is 240 degrees, and BC 272 cams have 272 degrees at 0.006 inches of lift. In the GM world, 0.050 lift is more commonly used, and those same cams would be referred to as 204 degrees and 222 degrees. The difference between the .006 and .050 durations depends on the cam's ramp rate. Two cams might have the same .006 duration, but if one has a more aggressive ramp rate it will have a larger .050 duration than the other. For example... I just noticed that the stock cam in my C5 was 204 degrees at .050, which is the same as the stock 05 LGT cam, which is a funny coincidence. But the duration at .006 degrees is 270 degrees for the Corvette, vs the 05 LGT's 240 degrees. So the Corvette has a much slower ramp rate. Perhaps because it has one huge heavy intake valve rather than two small light ones? I dunno. I got information for my 05's stock cams from a page out of a factory service manual, and it's exactly the same numbers as in covertrussian's 07-09 diagram. So maybe the cams are indeed the same, and lots of overlap just works better than I thought was possible.

I've made a lot of progress with my 05 but it still isn't quite as smooth as my wife's 09, especially after a cold start. So it finally occurred to me that I should compare the "Timing Compensation (ECT)" tables in both... They are both zero from 140-194F, but at lower temperatures the 09 ramps up gradually whereas the 05 stays zero until 50F and doesn't ramp up quite as much. So I re-did the 50-120F cells in my 05 based on the 09 table. I have about 1.5 degrees additional advance after a cold start at 50F (which is about what the temperature is out here), and as the engine warms up the advance tapers slowly rather than just going to zero at 68F. I've only done two cold starts so far (both today) but I think the extra advance is a win.

I can see how that would help, but 26 degrees of overlap at .050 is still hard for me to believe. Regardless of how nicely atomized the fuel is, random nontrivial amounts of it would be getting blown out the exhaust port at low RPM. Apparently with LS1s (not apples to apples but the cylinders are only slightly larger) you can't pass tailpipe emissions tests with any overlap at .050. Mine has 9 degrees, and it's prone to surging at low RPM (like 1500 RPM in parking lots). With 3x the overlap I'd expect the surging to continue into higher RPM.

I have chattering noise when there's zero load on the drivetrain, that's been there since day one. There's a mild descent that leads to my neighborhood that's just right for it. Otherwise it's pretty quiet.

Sorry to hear about your 2nd gear. I don't recall how long its been since mine went in but I think it's approaching a decade now. 35k miles, no issues.

Did you check for binding of the TIRE against the inside of the wheel well?

This issue with running smoother with 10-15 degrees of AVCS makes me think that Subaru must have changed the cam specs between the 05 and 09 years - presumably at the same time as the facelift. My wife's 09 is super smooth and it uses 40 degrees of cam advance. According to the specs I found for my 05 (here), that would mean 26 degrees of overlap at .050 lift, which seems like an unreasonably large amount. However, 10-15 degrees of advance would leave -4 to +1 degree of overlap at .050, which is totally reasonable. For comparison, my car (with BC272s and dual AVCS) is running -4 of overlap (maybe "4 degrees of separation" would be a better way to put it) and it's pretty smooth. Not as smooth as my wife's 09, but better than my 05 when it was stock.

If it were a locking center diff I'd expect the tires to scrub on the pavement at both ends of the car during turns. Nothing locks up, the fronts just scrub a little because they're not turning fast enough, and the rears scrub a little because they're trying to turn a little too fast. I've experienced this in 3 different cars - one with a bad center diff, one with no center diff, one with (aftermarket) DCCD. In all cases, the effect was small in slight turns and got progressively worse as I turned tighter. The car with the bad center diff wouldn't actually skid much at all unless traction was low, it just lugged the engine down because it needed extra torque to get the center diff's output shafts to move at different rates. If your car is fine until you turn the wheel past a certain point, and then that outer wheel locks up, that sounds to me like the center diff is fine and something is binding. And I'm guessing the binding comes from the inside shoulder of the tire colliding with the the wheel well, probably in front of the control arm and a little bit above it. There probably is a maximum front/rear difference but if the tires are less than 1% different the that's probably not the issue. Code has a good question regarding tire models though, if they're different then the tire dimensions can't really be compared, you'd have to measure to really know the difference between them.

The circumference will always be off by the same percentage as the diameter. Either way, his are off by 0.4% so I'm guessing his center diff is in no real danger.

The fact that a single wheel is locking up makes me think that's not really a center diff issue. I'd pull the front wheels off and look for signs of rubbing. 275 is a lot of extra width, so I wouldn't be surprised if the shoulder of the tire was just binding up against the wheel well. Or maybe it's the wheel binding against the control arm. Look at everything. I bet you'll see something. And/or... you could just pay very close attention to how much you can turn the wheel before you hear or feel any drag. Then don't turn the wheel that far anymore. And then keep us posted about how long your center diff lasts. My guess is that your tire diameters are close enough that it won't actually be a problem, but it's just a guess.

This is great. My favorite bit:

What changes have you made to the suspension?