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NSFW

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Everything posted by NSFW

  1. Yes, that's working well for me. Give it a shot and report back. I think it makes for a smoother transition between engine braking and cruising, and when getting back on the throttle after a shift. I barely messed with AVCS tuning over the years, partly because valve timing seemed too mysterious and partly because I was satisfied with how my car was running... Ironically what finally got me to study up on valve timing was buying a 2002 Corvette (Z06, whee!) which does not have variable valve timing. But that makes it even more important to pick the right camshaft, so I have been reading everything I can find, and I started experimenting with my Subaru. I'm still not very clear on how timing should vary with load, so I have more experimenting to do there. Making every column the same has worked out pretty well for cruise and low boost. I haven't paid attention to how it is affecting high boost yet but of course I'm getting curious. The main insights that led me to try the table I'm using now: * Of all of the valve events (intake open, intake close, exhaust open, exhaust close), the intake valve close (IVC) is the most important. * GM truck cams have the intake valve close at about 33 degrees after bottom dead center * Aftermarket Corvette cams mostly have an IVC around 45 degrees ABDC. ("Close" is measured at 0.050 lift, which is kind of a lie, but that's the convention.) I don't have specs for stock cams, but for the BC 272s that I'm using, 30 degrees of intake advance puts the IVC at 31 degrees. 2009 LGTs used 40 degrees advance for a small part of the AVCS table, and had about 20 degrees less duration (10 less on the open side, 10 less on the closing side), so I'm guessing that my IVC timing with 30 degrees of advance probably matches the stock cam at 40 advance. (That's assuming that my BC272s have the same the intake lobe centerline as stock cams. BC says the 272s have a 130 degree intake lobe center, but I don't know what the stock centerline is. If anyone does know, please share. I'm curious about the stock exhaust centerline too.) And then I take out 20 degrees of advance at high RPM for an IVC of 51, because the GM aftermarket sees fit to use 45 in cams that are optimized for high RPM... and I bet they would go further if they didn't have to worry about the effect on low RPM. That's sheer speculation that really needs to be tested, though... The car seems plenty strong this way but I haven't done any performance measurements yet. The stock AVCS table drops to zero before 5000 so I'm really curious which approach makes more power.
  2. You might notice that the far-left column in that table has 20 degrees of advance where the rest of the columns have 30. That's because the stock table used less advance at low load... but I just changed that column to match the others and I like the results. I think I'm also getting fewer knock-sum increments in cruise and during shifts now, but that's only based on 5-10 minutes of paying attention to knock-sum. I need to watch it more to see if that's for real or just chance.
  3. I didn't realize they had a performance shop, that's good news. The people at their maintenance shop in Kirkland are great. Details for anyone else who hadn't heard: https://www.driveautosports.com/
  4. I've been tinkering with AVCS for the last few days and I've all but eliminated the stumble. It's gone during cruise on level ground and there's just a hint of it in top gear going uphill. Basically, look at the load/RPM region where you get stumble, and add AVCS advance to that area (about 5 degrees), and blend it smoothly with the neighboring cells, and then test-drive... If it helped, or add a few more degrees (or extend your changes into wider load or RPM ranges) and test again. Also try going up and down mild hills to see what load you're running if/when the stumble happens. Try higher and lower RPM as well. For me the stumble was worst around 0.75 load and 2500 RPM, so I started adding more AVCS advance in that area, up to 30 degrees, and gradually expanding the region that uses 30 degrees, and eventually came up with the table shown below. I tested it earlier tonight, and so far it seems to work really well. The shape of this table is obviously a lot simpler than stock, and it might be too simple... I've not been trying to measure power output or anything else, so I imagine this will change as I do more tuning. I got about 5 iterations into the process I described above before deciding that more advance was helping so much that I was ready to scrap the old table and start over with something that has a much simpler shape to it. That may or may not have been wise, but I like the results so far. Two disclaimers: I have aftermarket cams (BC 272) and exhaust AVCS (08 STI heads) so 30 degrees might not be ideal for you. Heck, it's probably not even ideal for me, I'm still testing stuff. If more works better for you, use more. Or if you reach a point where adding advance makes the car run rougher, just take a few degrees back out. Don't copy the bottom few rows of this table - I am also experimenting with AVCS at higher RPM and I make no claim about this being useful. The stock AVCS table ramps down to zero at about 4500 RPM, and yours probably should too. (And no, I don't rev to 9000. I just wanted fewer cells to edit, so I made the last row unreachable.)
  5. My trans and diff are both from an 04/05 STI but I had Rallispec put Spec B 5th/6th gears into the trans. I think mine is the same as what they now call the DccdPro universal. It has two modes - in one mode, the knob adjusts the power to the center diff clutch pack, in the other mode the power is some magical function of throttle pedal (you have to tap into a wire near the ECU) and accelerometers, and the knob adjusts the overall strength. I honestly couldn't tell the difference on the road, and I never tracked the car with the 6MT setup. For either mode, I just turned it up until it started binding in tight turns (like parking lots) and then backed it down until it stopped doing that. Either way the main thing I noticed was that I couldn't spin the rear tires, which is reasonable, but less fun, so I mostly just turned it off. If I drove in snow a lot, or on steep snowy hills ever, I'd keep the DCCD controller. But it wasn't bad in snow with DCCD off. Mountain passes were just fine, it still drove like AWD. I was on snow tires though, might have felt differently using all-seasons on snow. (I later switched to an Outback for snowboarding trips, mostly just because I saw too many accidents on the pass. The Outback is near stock and therefore easily replaced. The Legacy is nowhere near stock I have spent tons of hours tinkering with it.) Adjustable torque split is a very misleading term, at least for every center diff I know of. Really what gets adjusted is the amount of slip that's allowed between the front and rear axles. Limited slip is better from a safety standpoint, but unlimited slip is more fun.
  6. There used to be two 6MT swap threads... mine got merged into that one. My recipe was copy-pasted into the first post though. I don't really know what the 6MT's limits are, but I'm pretty sure it's well over 500whp. DCCD is over-rated IMO. I'm running a DCCD trans without a DCCD controller and I'm perfectly happy with it that way. If I was racing I might feel differently about it, but I'm not. I had a DccdPro but generally ran with it disabled because spinning the rear tires is kind of fun now and then. So one day while screwing with wiring under the dash I removed it to get it out of the way... and didn't put it back... maybe one day, but probably not. I think I found a stronger gear set for the 5MT back in the day, but it cost about the same as a 6MT, so it wasn't very appealing. I don't remember any specifics but you might try PPG's web site. I know they make 6MT gear sets (for 15 or 20 grand).
  7. Also, part of the reason I went with that turbo was that I figured it was the biggest I could go without needing trans/diff/axle upgrades. And then a few months after I got it, two people here with about the same amount of power blew 3rd gear. LittleBlueGT was one, I forgot who the other was. So I went 6MT. I've you've over 400 your 5MT is probably not going to last forever. I have no idea how much "blast plates" will help, but it's an interesting idea. I don't remember those being an option back then.
  8. For comparison, my GT3076 made 377whp at 22 or 23psi. I'm guessing you'll be at the upper end of 'medium' or the low end of 'high' boost.
  9. NSFW

    Quotes???

    I think that might be backward, but let's see if we can get a consensus...
  10. It might be the front/rear torque split. Some cars were 35/65, others were 40/60, and if I remember right the rear diffs had different ratios that went hand-in-hand with that. So if you swap the center diff you'd also want to swap the rear diff at the same time.
  11. ...and about a thousand horsepower? #lifegoals ?
  12. I think it was also $1500ish when Rallispec did mine. I plan on keeping the car a long time so it seemed like a reasonable investment. I certainly like the results, but only you can decide whether you'd rather have $$ or low RPM.
  13. I joined at the end of 2005, bought my wagon in 2006, still have it. It had about 25k when I bought it, and about 85k miles on it now. I put fewer miles on it after I bought an Xterra for snowboarding trips, and fewer still after I broke the motor and spent a couple years trying to make up my mind about how to rebuild, but it's running again. When I joined, my girlfriend was driving an Audi, but we got married so now she has an 09 LGT sedan. And the Xterra got replaced with an 05 OBXT wagon for dirty work. And I bought a C5 Z06 a few months ago. According to the dyno sheets, it is just 6whp shy of my wagon.
  14. Left-lane-camping brake-checking genius... [ame=http://www.youtube.com/watch?v=9JrEf3-O2s8]Brake checking a cop... - YouTube[/ame]
  15. 9mm singlestack for the XC trails and .45 doublestack for DH...
  16. https://www.seattletimes.com/seattle-news/eastside/1-dead-1-injured-in-cougar-attack-on-eastside/ Really sad story. In hopefully never-related-news, a bunch of new trails just opened up a few miles from there. It's been almost 100 years since the last cougar attack in Washington State, but... still...
  17. Do vegans detest meteors?
  18. Oh, I'm with you. I still have the same bike, and no plans to replace it. And my everything-but-DH bike came as 27.5 and I'm riding it with 26ers. It has a flip-chip for shorter chainstays, but the difference is pretty subtle. Really it's just 26 for spite.
  19. $2500 for a carbon-framed bike seems like a pretty good deal. And you definitely save a lot buying a complete bike. I built a DH bike from parts in 2011 and while it was kinda fun, the depreciation is ridiculous... plus it's a 26" and those are totally out of fashion now. FWIW, the reach and stack measurements on that bike in size large are both about 1cm longer than the large NS Soda Evo Air that I bought a couple years ago. I'm 6'0" and I think my bike fits me perfectly.
  20. You can't call it a murder of crows unless you have probable caws. (Seen on facebook earlier today.)
  21. My 1x6 has 34 teeth on the biggest cog, and 11 on the smallest, so the range is about the same as an early 1x9 setup, before everybody went all crazy with the big cogs. I had a 3x9 setup where I eventually realized that the granny gear was more trouble than it was worth. Standing up and pedaling hard was more fun than sitting and spinning, and that got me thinking that I could live without really low gears. And then I replaced the biggest sprocket with a bash ring. Then I went to an off-the-shelf 11-36 1x9 setup and was perfectly content. Then I saw the thread about 11-34 with 1x6, and saw it as a fun project and an upraised middle finger to the bike industry. How could I pass that up? It does help that I don't have any long steep climbs where I ride.
  22. 1x10 has been around forever now. Like five years probably, which is two eternities in mountain bike time. The cool kids are rocking 1x12 now, with cogs the size of dinner plates. Seriously: I was content with 36 teeth on the biggest cog, so I didn't see much point in 1x11 or 1x12. And then I saw this thread on mtbr... http://forums.mtbr.com/29er-bikes/6-speed-cassette-ss-hub-please-post-your-setup-573783.html ...so now I'm rocking 1x6 with an 11-34 cassette on a Hope "single speed" hub (which oddly enough has room for 6 cogs). It took some experimenting to find parts to make it work, but it's been solid and I really like it.
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