Rear Diff clutch plates installed incorrectly from factory
Completed this months ago, but have just now run a couple weeks on daily driving. Working on tuning to get ready for first track day since build. Don't notice any chatter, or noise, no matter how tight turning radius. Using stock fluids, and slightly over filled as per other threads.
The subtlety of this might me lost on my car as I have changed a number of things during this build, which include custom valved Bilsteins for the track, rear link bushings, RRE rear sway, and Works front camber plates (-2.8). No track time yet, but hard on/off ramp accel demonstrates a totally new car. Much more neutral and very un evo/sti like as I am used to. I suspect however its predominantly the camber plates.
The subtlety of this might me lost on my car as I have changed a number of things during this build, which include custom valved Bilsteins for the track, rear link bushings, RRE rear sway, and Works front camber plates (-2.8). No track time yet, but hard on/off ramp accel demonstrates a totally new car. Much more neutral and very un evo/sti like as I am used to. I suspect however its predominantly the camber plates.
Last edited by fireroasted; May 24, 2012 at 10:13 PM.
Re-arranged the plates in my rear diff this weekend with the help of a friend. Took us roughly 8 hours (6.5 hours after taking out a half hour lunch break and an hour break to go to the store after running out of brake cleaner).
Initial impression is that this was totally worth it. The only "test" I've done so far is getting on a 180° highway on-ramp and getting on the throttle during the turn. The car stayed noticeably more neutral than previously; feels like the rear is doing it's part to help the car rotate instead of having the fronts doing all the work.
I have a time attack event next weekend, where I'll get the chance to really see the difference.
PS no clicking or other sounds during tight turns so far. Re-filled with OEM Diaqueen.
Initial impression is that this was totally worth it. The only "test" I've done so far is getting on a 180° highway on-ramp and getting on the throttle during the turn. The car stayed noticeably more neutral than previously; feels like the rear is doing it's part to help the car rotate instead of having the fronts doing all the work.
I have a time attack event next weekend, where I'll get the chance to really see the difference.
PS no clicking or other sounds during tight turns so far. Re-filled with OEM Diaqueen.
Re-arranged the plates in my rear diff this weekend with the help of a friend. Took us roughly 8 hours (6.5 hours after taking out a half hour lunch break and an hour break to go to the store after running out of brake cleaner).
Initial impression is that this was totally worth it. The only "test" I've done so far is getting on a 180° highway on-ramp and getting on the throttle during the turn. The car stayed noticeably more neutral than previously; feels like the rear is doing it's part to help the car rotate instead of having the fronts doing all the work.
I have a time attack event next weekend, where I'll get the chance to really see the difference.
PS no clicking or other sounds during tight turns so far. Re-filled with OEM Diaqueen.
Initial impression is that this was totally worth it. The only "test" I've done so far is getting on a 180° highway on-ramp and getting on the throttle during the turn. The car stayed noticeably more neutral than previously; feels like the rear is doing it's part to help the car rotate instead of having the fronts doing all the work.
I have a time attack event next weekend, where I'll get the chance to really see the difference.
PS no clicking or other sounds during tight turns so far. Re-filled with OEM Diaqueen.
what kinds of vibrations? I get clunking/banging in tight turns, but its not vibrating or something during (cusco) - some people have noticed other stuff, not sure about the vibration
I have not noticed any vibrations or clicking/clunking. I do have trailing link bushings, which transmit road imperfections through the rear. They went in when I did this mod. I also have custom valved MR Bilsteins which are pretty hard.
I have done lots of DD miles with lots of tight round a bouts in my area, and nothing. However, I have not tracked yet (still trying to figure out how to tune this thing now).
I did overfill with stock fluid as per another thread I read, and a conversation with one of the trans shops. i forget who suggested that. Maybe Jack's. You can use a simple 10 dollar hand pump to fill and makes it super easy to just over fill a bit. You can also tilt the car a bit.
I did it on the bench before I put it in, so i could tilt almost 45 degrees. I will post my after track result if I can get a safe enough tune going by next weekend for Laguna Seca. The turn into the straight away will induce a clunk if anything will.
I have done lots of DD miles with lots of tight round a bouts in my area, and nothing. However, I have not tracked yet (still trying to figure out how to tune this thing now).
I did overfill with stock fluid as per another thread I read, and a conversation with one of the trans shops. i forget who suggested that. Maybe Jack's. You can use a simple 10 dollar hand pump to fill and makes it super easy to just over fill a bit. You can also tilt the car a bit.
I did it on the bench before I put it in, so i could tilt almost 45 degrees. I will post my after track result if I can get a safe enough tune going by next weekend for Laguna Seca. The turn into the straight away will induce a clunk if anything will.
Last edited by fireroasted; May 30, 2012 at 06:05 PM.
Mine is slightly overfilled as well.
Went for a little drive to purposely make tight radius turns to check clicking/clunking and see if I'd get vibrations again. There was some clicking/clunking as before, but no vibrations this time.
http://www.youtube.com/watch?v=DExJl8jRg3A
Went for a little drive to purposely make tight radius turns to check clicking/clunking and see if I'd get vibrations again. There was some clicking/clunking as before, but no vibrations this time.
http://www.youtube.com/watch?v=DExJl8jRg3A
Yikes, good video to really get the experience across. I can tell you that I don't have anything remotely similar to that. I can't think of what I would have done differently in this right up. I think I put the whole plate unit in the wrong way around at first and caught that error. i think its back a few pages. But if you did that, I think your behavior is that you essentially would not have any diff locking because its the wrong way (You'd get it in reverse or something weird like that). I think the answer is back in this thread. But you clearly have it locking and binding up.
Were any of your plates worn particularly? If they were and you have faces against each other that aren't partners since being new, I suppose they could be bucking each other . Fractions of a mm make a difference here I believe.
Did you have them out long enough or dry any of them. Some posts indicate to make sure and let the fluid get back between them very well.
Were any of your plates worn particularly? If they were and you have faces against each other that aren't partners since being new, I suppose they could be bucking each other . Fractions of a mm make a difference here I believe.
Did you have them out long enough or dry any of them. Some posts indicate to make sure and let the fluid get back between them very well.
The diff is almost certainly locking the right way, I got on the throttle in a sweeping highway on-ramp and I could feel the rear tires were doing more work.
The plates seemed to be in pretty good condition. They were all sprayed down with brake cleaner and dipped in diff oil before being reinstalled.
The only thing I can think of is that there could be little grains of dirt/sand/etc that got in the diff housing while it was open. I could drain the diff and put in some fresh oil, should rule out that possibility.
The plates seemed to be in pretty good condition. They were all sprayed down with brake cleaner and dipped in diff oil before being reinstalled.
The only thing I can think of is that there could be little grains of dirt/sand/etc that got in the diff housing while it was open. I could drain the diff and put in some fresh oil, should rule out that possibility.
The only thing that jumped out at me when I read that, was that you used brake cleaner on the disks. I did not, and on purpose. brake cleaner, though it evaporates and trap in the residual oil in extreme cases, and cause the new oil not to operate as expected.
My guess at this point is that you cleaned that stuff too much, and over time the oil will penetrate in there again. I know you stated you re oiled the plates before you put them in, but this is the most logical for me.
I did not clean them at all. They were very 'clean' or oiled when I took them apart. The worst contaminant was my possibly dirty latex gloves. I had them out for days, (the car was in pieces so no rush), and no dirt got into or on them.
You would have had to drop them or something to get them dirty. Changing the fluid can't hurt, but it wouldn't get anything out between the disks. Only use could drive foreign objects out of that pressured space, or disassembly.
I would think you just are getting areas to slip on each other that don't have as much oil on the surfaces as should be, or at least, as mine has, post mod. That explains the biting clunking as its ratcheting rather then sliding during that friction.
In general I don't use brake cleaner on parts that are immersed in oil for their intended use. I use different oil, or oil under pressure to try and clean. My dad was a machinist so that is just left over from the way he showed me old school things decades ago.
My guess at this point is that you cleaned that stuff too much, and over time the oil will penetrate in there again. I know you stated you re oiled the plates before you put them in, but this is the most logical for me.
I did not clean them at all. They were very 'clean' or oiled when I took them apart. The worst contaminant was my possibly dirty latex gloves. I had them out for days, (the car was in pieces so no rush), and no dirt got into or on them.
You would have had to drop them or something to get them dirty. Changing the fluid can't hurt, but it wouldn't get anything out between the disks. Only use could drive foreign objects out of that pressured space, or disassembly.
I would think you just are getting areas to slip on each other that don't have as much oil on the surfaces as should be, or at least, as mine has, post mod. That explains the biting clunking as its ratcheting rather then sliding during that friction.
In general I don't use brake cleaner on parts that are immersed in oil for their intended use. I use different oil, or oil under pressure to try and clean. My dad was a machinist so that is just left over from the way he showed me old school things decades ago.
The only thing that jumped out at me when I read that, was that you used brake cleaner on the disks. I did not, and on purpose. brake cleaner, though it evaporates and trap in the residual oil in extreme cases, and cause the new oil not to operate as expected.
My guess at this point is that you cleaned that stuff too much, and over time the oil will penetrate in there again. I know you stated you re oiled the plates before you put them in, but this is the most logical for me.
I did not clean them at all. They were very 'clean' or oiled when I took them apart. The worst contaminant was my possibly dirty latex gloves. I had them out for days, (the car was in pieces so no rush), and no dirt got into or on them.
You would have had to drop them or something to get them dirty. Changing the fluid can't hurt, but it wouldn't get anything out between the disks. Only use could drive foreign objects out of that pressured space, or disassembly.
I would think you just are getting areas to slip on each other that don't have as much oil on the surfaces as should be, or at least, as mine has, post mod. That explains the biting clunking as its ratcheting rather then sliding during that friction.
In general I don't use brake cleaner on parts that are immersed in oil for their intended use. I use different oil, or oil under pressure to try and clean. My dad was a machinist so that is just left over from the way he showed me old school things decades ago.
My guess at this point is that you cleaned that stuff too much, and over time the oil will penetrate in there again. I know you stated you re oiled the plates before you put them in, but this is the most logical for me.
I did not clean them at all. They were very 'clean' or oiled when I took them apart. The worst contaminant was my possibly dirty latex gloves. I had them out for days, (the car was in pieces so no rush), and no dirt got into or on them.
You would have had to drop them or something to get them dirty. Changing the fluid can't hurt, but it wouldn't get anything out between the disks. Only use could drive foreign objects out of that pressured space, or disassembly.
I would think you just are getting areas to slip on each other that don't have as much oil on the surfaces as should be, or at least, as mine has, post mod. That explains the biting clunking as its ratcheting rather then sliding during that friction.
In general I don't use brake cleaner on parts that are immersed in oil for their intended use. I use different oil, or oil under pressure to try and clean. My dad was a machinist so that is just left over from the way he showed me old school things decades ago.
The track will also heat them up real good, so the oil with thin and penetrate more easily. Let us know about the balance, and if the clunking continuous the days after the track. Good Luck!
Had a chance to take put he rearranged diff through its paces yesterday during Time Attack. It did not dissapoint. Helped me shave almost a second off my previous best lap time. (Went from 1:02.5 to 1:01.6).
The biggest noticeable difference was in a sweeping 180° third gear double apex corner. I could get on the throttle much sooner and harder and the car would continue on it's intended path rather than push wide. There's still more time to shave off, as even in my last session of the day whe nI was starting to get used to the diff I still found myself coming out of that corner thinking "yep, could've floored it a bit sooner".
Totally worth the hassle in my case.
The biggest noticeable difference was in a sweeping 180° third gear double apex corner. I could get on the throttle much sooner and harder and the car would continue on it's intended path rather than push wide. There's still more time to shave off, as even in my last session of the day whe nI was starting to get used to the diff I still found myself coming out of that corner thinking "yep, could've floored it a bit sooner".
Totally worth the hassle in my case.