StarquestRescue Posted November 9, 2008 Author Report Share Posted November 9, 2008 (edited) You can also swap in an extra spring for one of those drive plates for more clamping force (pre-load). Your talking about replacing the extra friction plate with a spring disk instead of a friction disk in the re stack? This would let one donor diff tighten up two lsd's instead of just one. Have you tried this. how does it compare? It was tricky keeping the spring plate lined up with the slots to get the diff cover back on. I cranked on the screws to hard on the first try and nicked up the housing. Some how had an extra plate in there, that didn't work out to well. Once i had the spring plate lined up on one side, i lay-ed the diff on its side and loosened the cover on the high side and taped on it. It seemed to help the spring plate line up with the slots. You can see the difference in the stack after assembly. Old stack http://i237.photobucket.com/albums/ff45/StarquestRescue/60457f49.jpg New stack http://i237.photobucket.com/albums/ff45/StarquestRescue/7b63445e.jpg Both diff housing had these were marks from the friction plates. Marks were worse in the donor diff from the car that snapped an axle. Pictures are of the donor diff housing. http://i237.photobucket.com/albums/ff45/StarquestRescue/1db73d76.jpg Edited November 9, 2008 by StarquestRescue Link to comment Share on other sites More sharing options...
Chad Posted November 9, 2008 Report Share Posted November 9, 2008 I haven't driven mine, just bench theory. I had dimples in my housings, but no where near what yours looks like. 1 Link to comment Share on other sites More sharing options...
StarquestRescue Posted November 10, 2008 Author Report Share Posted November 10, 2008 I indexed the coupler and the run out dropped to .004. The seals and cover are on. Hope to get it in the car next friday. I need to do a clutch job also so i don't think i will make it to the track next friday. There should be a special grease for the coupler i think? We had some real sticky grease at work we used on the spline drives of hydralic pto pumps. Link to comment Share on other sites More sharing options...
Chad Posted November 10, 2008 Report Share Posted November 10, 2008 I use axle greese on mine. Link to comment Share on other sites More sharing options...
Shelby Posted November 11, 2008 Report Share Posted November 11, 2008 threads like this should be clean'd up once they are done and place'd in the FAQ awaiting to hear you yes or no on how you like the gear drop , only bad thing is the real fast 1st gear , but with control'd wheel spin it shouldn't be that bad Link to comment Share on other sites More sharing options...
StarquestRescue Posted November 15, 2008 Author Report Share Posted November 15, 2008 Early on i thought the pinion depth gauge would minimize the trial and error. I had the 3.90 pinion in two different starion housings and it was telling me the 3.90 sat .035 lower than it did in the truck housing. I rolled the dice and added the .035 to the original shim. It was not even close, way to many shims. I then tried the original starion housing .065 shim (truck housing shim was .064). That was to little, went to .075,that was to much. Ended up at .069. In all 9 pinion shim changes. When i put the new bearings on and it threw of the pattern, the gauge would have given me an ideal how much, but i had not taken a reading before the change. Repeat ability with the gauge was good in the same housing. I don't know where the error came from. The original side shim pack totaled .250 between the two sides, i was able to get .255 of shims back in to tighten up the side bearing preload. I had reused the original side bearing and races, taking care not to mix the parts up from there original locations. At first i was only checking back lash at one location. This was a mistake as it varied around the gear .002 to .003. At a given pinion height there was 2 or 3 possible back lash choices. Since the 3.90 had run at .005 in the truck housing that was my target. I probably fussed over it to much, but the experience should pay off when i do the next one. I should get it in the car this weekend. Link to comment Share on other sites More sharing options...
Chad Posted November 15, 2008 Report Share Posted November 15, 2008 so when can I send you my 4.22 set and housing? Link to comment Share on other sites More sharing options...
Shelby Posted November 15, 2008 Report Share Posted November 15, 2008 :hmm3grin2orange: Link to comment Share on other sites More sharing options...
TurboRaider Posted November 15, 2008 Report Share Posted November 15, 2008 Two tricks come to mind for diff setup. One is to use a spare set of bearings for the setup that have been honed out and hopfully match in height to the bearings you will use for final assembly. You can use a spare polished down pinion shaft that slip fits both of them and compare them in the diff housing to be sure they match. This trick works really well. That will get you very close on gear setups, as with any gear setup that last few tenths are hard to get just right. The other method I use is to polish down the pinion that I will be using to have a very tight slip fit. I set up the diff that way get the shims just right and then use Loctite stud and bearing mount for final assembly. Its never failed me in 20 + years, although you need to use heat and a press if you ever try to take the pinion apart. Make sure you use cleaner on the parts for final assembly as well as the Loctite primer. Also on hard to set up gears where the factory shims selection is either too tall or the next shim is too thin I will take a few tenths off the tall shim using a surface plate and a piece of 600 grit abrasive paper. I set up some very used 4.62 gears with 340,000 miles and they crown on the gear teeth was worn enough that a tiny change in the pinion height moved the pattern a lot. Sure new gears would be nice but.... I set the pattern up slighly inboard so it centered under load and they are nice and quite. Tiny bit of noise under coast but I expected that when I moved the drive pattern. They are way better that how they were before I set re-set them up. Kevin C Link to comment Share on other sites More sharing options...
Shelby Posted November 19, 2008 Report Share Posted November 19, 2008 well week end is over,get to try that diff out yet Link to comment Share on other sites More sharing options...
StarquestRescue Posted November 20, 2008 Author Report Share Posted November 20, 2008 It was raining out so i had to clean up the garage to get the car in. One of the mounting ears had bad egged out threads. I ran a 1/2" fine thread tap through it (just a tad bigger than 12mm 1.25 and nearly the same thread pitch) and picked up a 1/2" NC grade 8 bolt. Maybe this friday, but sat and sunday i can't work on it. Cleaned up the old brackets. http://i237.photobucket.com/albums/ff45/StarquestRescue/2d315a97.jpg Old rear is out. http://i237.photobucket.com/albums/ff45/StarquestRescue/b9531853.jpg Link to comment Share on other sites More sharing options...
StarquestRescue Posted November 21, 2008 Author Report Share Posted November 21, 2008 (edited) Some goodies from my stash. http://i237.photobucket.com/albums/ff45/StarquestRescue/e7a441f9.jpg http://i237.photobucket.com/albums/ff45/StarquestRescue/e52eb64e.jpg This is how i pull a rear. It just needs to drop down a little so the input flange will go over the cross member. http://i237.photobucket.com/albums/ff45/StarquestRescue/33daca69.jpg http://i237.photobucket.com/albums/ff45/StarquestRescue/ebfe517b.jpg A swivel socket for the diff mounts. http://i237.photobucket.com/albums/ff45/StarquestRescue/b9c56765.jpg http://i237.photobucket.com/albums/ff45/StarquestRescue/4731f85f.jpg http://i237.photobucket.com/albums/ff45/StarquestRescue/534088e0.jpg Edited May 31, 2009 by StarquestRescue Link to comment Share on other sites More sharing options...
StarquestRescue Posted November 21, 2008 Author Report Share Posted November 21, 2008 My exhaust donut suspension mod to reduce up and down movement at the cross member bushing.. Clean the donut up than spray some silicon on them and the retainer piece. Still wheel hops some but i swear it made a difference. Back to work now. http://i237.photobucket.com/albums/ff45/StarquestRescue/6af7aece.jpg http://i237.photobucket.com/albums/ff45/StarquestRescue/8a8302ca.jpg Link to comment Share on other sites More sharing options...
StarquestRescue Posted November 27, 2008 Author Report Share Posted November 27, 2008 (edited) I road tested the 3.90 tonight. I was doing slow full lock turns in a parking lot near my house and sure as crap a cop pulls in. Eye balls the expired inspection sticker and says what are you doing? I tell him i just put the rear in and i am lubricating the LSD plates. He says if you were trying to do donuts you were doing a poor job. He lets me off on the inspection and says do what you gotta do. So i took it for a 20 mile run. :character0028: It ran good, no noise. It is a good match for my 245 50 16 drag radials. The LSD is definitely tighter. No chatter n a slow corner, but i can really feel it if i gas it a little. I was pretty gun shy about getting on it after my meeting with the cop. I hope to get to the track this weekend, i hope the cop does not see me. Rpm at 70 mph. 3.90 with 245/50/16 =3068 3.90 with 225/50/16 =3165 3.54 with 225/50/16 =2866 Edited November 27, 2008 by StarquestRescue Link to comment Share on other sites More sharing options...
Shelby Posted November 30, 2008 Report Share Posted November 30, 2008 so you want us to beleave you never once punch'd it to feel if there was a diff Link to comment Share on other sites More sharing options...
StarquestRescue Posted December 1, 2008 Author Report Share Posted December 1, 2008 Well i have about a 100 miles on it. So far i like it, the 19c doest feel so laggy any more. I was concerned i would not be able live with it on the street but i don't mind the extra rpm at 65 mph. Have not really cruised yet at 70 or more. The LSD re stack definitely works, i haven't seen a down side to it yet. It will fire stray rocks out the back with out even getting on it making a sharp turn at an intersection. I did a burn out at the track and it instantly when side ways. I decided to run my 245/50/16 street tires at the track. Big mistake, 30 degree track temp, street tires and 3.90's = instant wheel spin. I dilberately tried to bog it with a 2500 rpm launch and it still spun. The gear changes come up real fast and i was missing my shift points and slow on the shifts. I was skipping the burn out to keep the heat out of the dying clutch, since that was not working i did a burn out and got my best run. 14.102 @ 101.95 with a still crappy 2.237 60' at 17lbs of boost. For a good comparison to my best runs with the 3.54 i need to pull a low 2.0 60' with no bog. That will take my Mickey Thompson's and a hard launch, but the clutch is not really up to that any more. I have a used and abused act extreme pp i might try. There are 2 more saturday test and tunes. I kept thing about my friends dyno chart that shows these cars going lean in a hurry over 5000 rpm at these power levels. .I was going threw the traps at an indicated 5400 rpm. The calculator says the rpm was more like 5200. Rpm after a shift was about 4000 rpm. Here's my dyno chart at similar boost and air temp. http://i237.photobucket.com/albums/ff45/StarquestRescue/fd9e333a.jpg http://i237.photobucket.com/albums/ff45/StarquestRescue/f2229b72.jpg Link to comment Share on other sites More sharing options...
Technology Posted December 1, 2008 Report Share Posted December 1, 2008 Well, if you are reading the stock tach, I wouldn't trust it. Mine is just a lie now, might have something to do with the unsheilded signal wire. This is an awesome thread, and I really want to do the same thing you did with the clutch plates. I have a spare 88 diff sitting around, so I will probably do that. Also, I'm really surprised you aren't going faster with that 19c. I was doing 14.2 @ 100mph with the 12a at 18psi and bald street tires hopping all the way through 1st. btw, to eliminate wheel hop, drop the tire pressure. Link to comment Share on other sites More sharing options...
StarquestRescue Posted December 1, 2008 Author Report Share Posted December 1, 2008 (edited) This is an awesome thread, and I really want to do the same thing you did with the clutch plates. I have a spare 88 diff sitting around, so I will probably do that. Also, I'm really surprised you aren't going faster with that 19c. I was doing 14.2 @ 100mph with the 12a at 18psi and bald street tires hopping all the way through 1st. You can get the friction discs from a 4 bolt 85.5-87 4 bolt LSD, don't canibalize a 6 bolt if you can avoid it. I am disappointed in the 19c, maybe it would work better with mpi but i liked the 17c better. My car will go quicker when it hooks up and i get the shift timing down. :biggrinumbrella1: I know a lot of guys can out shift me and that makes a big difference. I have been stock piling automatics, but the 3.90's were a prerequisite to that. My best times to date. 14g 13.770 @ 100.98 1.987 60' 17c 13.630 @ 101.57 2.016 60' On M/T ET tires 19c 13.741 @ 102.80 2.016 60' On Nitto DR's 19lbs of boost. Edited December 1, 2008 by StarquestRescue Link to comment Share on other sites More sharing options...
Shelby Posted December 1, 2008 Report Share Posted December 1, 2008 isn't the 17c and the 19c still useing the stock mits houseing, if so they both would gain from waste gate porting increases the top end flow a bunch Link to comment Share on other sites More sharing options...
StarquestRescue Posted December 1, 2008 Author Report Share Posted December 1, 2008 isn't the 17c and the 19c still using the stock mits housing, if so they both would gain from waste gate porting increases the top end flow a bunch Both TD05h in the stock exhaust housing. The 19c has a 15 degree clip on the turbine which i believe is standard for a 19c. I am going to ask my turbo guy about the wastegate porting when i get some time and money on my hands. All of my turbos have inlet porting already. Link to comment Share on other sites More sharing options...
StarquestRescue Posted December 7, 2008 Author Report Share Posted December 7, 2008 (edited) I got to the track today. One friend donated a used ACT extreme pressure plate and another a dykum disk slightly better than mime. It is not quite fully disengageing and i think that slowed my shifts a little. I ran my 26" MT ET street tires. Still having trouble with late 1/2 shifts, especially if i pedal it due to tire spin or wheel hop. Air temps were in the low to mid 30's. The air could have been dryer, there was a front moving in and it started to snow after i got home. http://i237.photobucket.com/albums/ff45/StarquestRescue/th_abf00397.jpg Dec 6 08. 3.90 gears in my car. My best 5 out of 9 runs. I also wasted a 1.871 60' and a good 1 to 2 shift when i missed third gear. I got a new personal best mph, 60' (the 1.871 i wasted) and i think my fourth best ET. 13.783 @ 103.32 1.980 60' 13.951 @ 101.97 2.118 60' 14.061 @ 102.79 2.014 60' 14.017 @ 102.96 2.060 60' 14.122 @ 103.65 2.053 60' By comparison my friend Chris. A 17c car with better exhaust and a few other things that dynoed 25 hp more than mine.He was having trouble with wheel spin. He can also out shift me. I am sure he had more 13'teens but these are from the runs we were paired up. He probably made 15 runs. 13.857 @ 102.80 2.126 60' 13.909 @ 102.43 2.164 60' 13.952 @ 103.51 2.188 60' So far i like the gears on street, but haven't seen a big difference at the track. But i know lazy or late shifts hurt some of my times. After i zinged the motor on the missed shift (after the 13.78 run), i was a little conservative on my shifts and my et's were a little slow for the 60' and mph after that. I will say that first gear did not need to be any shorter. Edited December 7, 2008 by StarquestRescue Link to comment Share on other sites More sharing options...
Shelby Posted December 7, 2008 Report Share Posted December 7, 2008 (edited) what was that ,, a turkey gobble on the 2-3 shift ? no bov ? over all a nice days work the 100's of a sec at harder to drop after 14 sec Edited December 7, 2008 by Shelby Link to comment Share on other sites More sharing options...
Technology Posted December 7, 2008 Report Share Posted December 7, 2008 "that impala looks like one'a them big GMC trucks" Your videographer friend knows a lot about cars, doesn't he? Link to comment Share on other sites More sharing options...
StarquestRescue Posted December 7, 2008 Author Report Share Posted December 7, 2008 (edited) what was that ,, a turkey gobble on the 2-3 shift ? no bov ? over all a nice days work the 100's of a sec are harder to drop after 14 sec Yes i heard that also. The blow off sounds different since i put on the 52mm TB. I did not realize it was a problem till now, i need to look into that. "that impala looks like one'a them big GMC trucks It was "cop car day" There were 4 impala ss and or former cop cars there and one Merc marauder. Some off them were flying. There is a lot to be learned from vidio. Next time i will ask him to shoot from more locations. I would like to get a better ideal where on the track my gear changes are at. A camera mount inside the car would be neat also. I don't know who was talking on the vidio. I do want to thank the guy that shot the vidio and also drove the support truck with our drag tires,jack and tools. Edited December 7, 2008 by StarquestRescue Link to comment Share on other sites More sharing options...
StarquestRescue Posted December 7, 2008 Author Report Share Posted December 7, 2008 (edited) More vidios 1 vidio and time slips added 12/18/08 Cop car whoops my friend. http://i237.photobucket.com/albums/ff45/StarquestRescue/th_753510e0.jpg 13.81 http://i237.photobucket.com/albums/ff45/StarquestRescue/th_184eabce.jpg Heads up http://i237.photobucket.com/albums/ff45/StarquestRescue/th_a6e722b5.jpghttp://i237.photobucket.com/albums/ff45/StarquestRescue/983bec13.jpg Heads up again http://i237.photobucket.com/albums/ff45/StarquestRescue/th_74fb9199.jpghttp://i237.photobucket.com/albums/ff45/StarquestRescue/6d19abbd.jpg 103.51 mph Edit, i lifted when the engine stuttered in 4th gear http://i237.photobucket.com/albums/ff45/StarquestRescue/th_9f5941c0.jpghttp://i237.photobucket.com/albums/ff45/StarquestRescue/1b208573.jpg 103.65 vs 102.80 http://i237.photobucket.com/albums/ff45/StarquestRescue/th_b764d06f.jpghttp://i237.photobucket.com/albums/ff45/StarquestRescue/5f8491b7.jpg Edited December 19, 2008 by StarquestRescue Link to comment Share on other sites More sharing options...
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