cygnusx1

Wow really nice! Just tell people that its a really, really, long two cylinder engine.

I got unlucky in that the internal OBX gears were backwards but I got lucky in that the OBX measured within 0.001 to all the width and ring gear location to the original open center. Yes the OBX needed to be coaxed into place with a mallet. There are no bolt head interferences....yet! BTW here is the McMaster Part for 12mm to 10mm bushings for the ring gear bolt adaptors. 10 needed. 6679K14 http://www.mcmaster.com/nav/enter.asp?partnum=6679K14 On another note. I had my dad apply torque to the input shaft of the diff while I tried to turn the side shafts in opposite directions. It works. I could not break the breakaway torque with two long screwdrives wedged in the stub axle studs, when my dad applied input torque. Pretty cool.

It looks like my OBX unit is going to be a drop-in with the factory shims that came out. I need to double check but so far I get about 0.005"-0.007" backlash on the ring gear. I also set the belville washers with about 10ft/lbs of initial break-away torque (preload). I just didn't feel comfortable setting zero preload for fear of gear rattles, or too much preload for fear of excessive wear, so I took a conservative approach. We will see how it works hopefully in a month or so. Snow melts.

Yup, ACT recently changed their pressure plate design when they went to in-house manufacturing, so my 5 year old pressure plate will not work with sprung-centered discs. My pressure plate will only fit the solid ACT racing discs. Here is their email: Dave, Thank you for your e-mail and support of ACT products. A few years back we started manufacturing everything in house. We have changed the design on our discs as well as the pressure plates. With the use of our current sprung centered discs, you will need to use our current pressure plate as well. Attached below is a list of kits with power ratings and breakdown of individual component part numbers. If you have any other questions, please contact us using the information below. NISSAN FLYWHEEL # KIT # TQ CL P/PL SFI DISC SFI RB PB AT 280Z, ZX 79-83 NX2-HDSS 400 42% N013 @ 3000405 @ RB016 PB1012 AT01 2+2 & Turbo NX2-HDG6 * 512 42% N013 @ 6240306 @ RB016 PB1012 AT01 240mm NX2-HDG6 * 512 42% N013 @ 6240306 @ RB016 PB1012 AT01 NX2-HDR6 * 512 42% N013 @ 6240006 @ RB016 PB1012 AT01 NX2-HDR4 * 512 42% N013 @ 4240006 @ RB016 PB1012 AT01 NX2-XTSS 490 74% N013X @ 3000405 @ RB016 PB1012 AT01 NX2-XTG6 * 630 74% N013X @ 6240306 @ RB016 PB1012 AT01 NX2-XTG4 * 630 74% N013X @ 4240206 @ RB016 PB1012 AT01 NX2-XTR6 * 630 74% N013X @ 6240006 @ RB016 PB1012 AT01 NX2-XTR4 * 630 74% N013X @ 4240006 @ RB016 PB1012 AT01 Regards, Richard Weiser Sales & Tech Support Advanced Clutch Technology, Inc. 206 East Avenue K-4 Lancaster, CA 93535 (661) 940-7555 Ext.107 http://www.advancedclutch.com

Really cool. I wish I could get on an airfield to take photos of the car with planes. Car looks awesome.

I notified OBX about this issue through their website and linked them to this thread.

Mine was stolen. Someone got a good deal on that one.

This turned into a "while I'm at it".....I will be selling my 225mm ACT Pressure Plate with 40% used solid 6-puck disc. The whole setup has less than 15K miles on it. It's in good condition. I was going to re-use it but since my new disc doesnt fit, I upped to a 240mm pressure plate which will also fit the new fidanza flywheel. This is not the for sale section and I don't have photos of it yet but I will post tonight. Price will be very reasonable. The setup was rated to about 400+ft-lbs by ACT.

I just bolted up my Fidanza flywheel and took off my 225mm ACT pressure plate and solid 6-puck disc to replace it with a sprung 6-puck disc. The new ACT disc appears to be 225mm and the ACT Pressure Plate is 225mm but the sprung center section of the disc wont fit into the pressure plate! I don't know what the deal is. I emailed ACT with all the part numbers. We will see. Worst part is that the disc is a brand new but has sat in my garage for over a year now. I don't even remember where I bought it. Frustration. To do list: -Clutch -Test fit Hokes Z32 tranny for exhaust clearance -install OBX LSD, diff seals, and shim diff -regrease 280ZX axles -find 280ZX 5-speed if Z32 wont clear. -short shift kit -install camber bushings in rear control arms -wait for ice and snow to melt, and wait for rain to wash away road salt.

It was so icy here today that I slid down my driveway backwards at a walking pace with my WRX with four Blizzaks on it. I was able to get back up, but barely.

I didn't think a P90 would fit a Mazda.

I would be into getting together somewhere in the NY area. I recently did the Grand Prix go-karts and it was really fun. We could do that and get some drinks afterwards.

OBX Mystery clunks and washer disintegration possibly solved! Time and miles will tell. Maybe I should call OBX and tell them. LOL. Look another person figured the same thing out here: http://forums.clubrsx.com/showthread.php?t=520556

Holy Hopping Snot! I swapped the positions of the helicals and the side gears left to right and now the OBX thrusts OUTWARDS during acceleration! NOW it makes sense! This way it wont bash the washers when you punch the throttle. The only thing the washers will see is pressure from heavy engine breaking. I think this is the ULTIMATE solution to make the OBX function like the Quaife. Albeit probably not as smoothly and as durable but MUCH better than when the gearsets were backwards!

Bingo...what I was saying. But can you really just flip the gears? It's like putting a propeller on the boat backwards. The boat still goes forwards? No? lol

These are the screws that came in my unit. I don't have a Quaife to study, but from all the cutaway's I see, the OBX and the Quaife work oppositely. The OBX forces the side gears toward eachother under acceleration and the Quaife forces the side gears apart during acceleration. This might have gotten them around any patents that might be involved. If my assumptions are correct, and I very well could be wrong, then OBX should have put the bellville springs outside of the side gears, forcing them inwards to take up slack. This design reversal could explain the abuse imposed upon the OBX washers and the slack felt in some peoples driveline when going from accel to decel. NOTE THE OPPOSITE ANGLE OF THE SIDE GEAR TEETH: OBX Quaife

OK I played around with the OBX on the floor of my house (too cold in the garage). This is how it works. The large side gears are splined correctly for the 280Z 280ZX inner axle stubs. When forward torque is applied to the ring gear, the left and right side gears are PULLED into eachother, towards the center of the diff. This is due to the spiral (angle) cuts in the gears. Sandwiched between them is the star shaped "clutch" that is filled with spring washers. The spring washers are compressed by the two colliding side gears as the side gears bite onto the central "star" shaped "clutch". On neutral input torque, the spring washers push the side gears back outwards, away from the central "star-clutch" and into the inner walls of the gear case. In reverse torque on the ring gear (engine braking) the side gears are forced outwards into the inner walls of the gear case. There is also friction created from all the thrusting around of the thinner spiral gears as they press into their pockets and their ends drive into the case walls under pressure. (point to note: the groove inside the side gears for the axle retainer ring is made extra wide to allow the side gears some side to side action without pulling on the axles) BOTH decel and accel will produce some level of LSD action. THE SPRING WASHERS: They are merely there to keep the outer gears from slopping around during transistions from accel to decel. If the stack is too short, you get slop and the gears rattle. If the stack is too long, you get some preload when you screw the case together and the diff will never act like a FULLY OPEN diff. The spring preload forces the side gears outwards to press against the inner case walls. NOTE: If the outermost spring washers are installed (xxxx) the end of the stub axles CAN rub into them. I reccommend installing the outermost washers like this )xxxx( I chose to assemble with one-washer-thickness of preload. Using the McMaster washers I did this: ))()()(( This makes the diff slightly preloaded with hopes of keeping the slop to a minimum when getting on and off the throttle. R200 280Z Axle Stubs:

OBX WASHERS AS THEY CAME OUT

I think you are good with the quaiffe. It's just us penny pinchers that need to be concerned about the OBX units. I began taking my OBX apart tonight for a washer change and inspection. Structurally and quality-wise, it seems quite good. The metals used seem very hard. I will check the stubs if I get time. I was told by another member that uses the OBX, that the 280Z and 280ZX inner stubs fit fine. I will double confirm when I can. Pics on the way

Bought it on ebay from "tuna-tom". It's at home today and I may open it up tonight to swap the washers and clean/debur if needed. First thing I will check is that the 280Z/ZX inner stub axles fit in it...it's an S14 unit for an R200 so they should fit. 29spline 30mm. Hopefully I have enough shims around that I can get the backlash correct.

Hmmm choices. Enjoy the steaks....I won't comment on the other decision. Happy Birthday! Many, Many, More.

I would ask Dave at Arizona Z Car about that. He has advised me well in the past. Congrats on the great choice of brakes!

OK I am going to get a little deeper here. Time is flexible. Doesn't every year seem to go faster and faster than the previous year? I think there is a connection to these feelings and the flexibility of time. I think we are either accelerating or decelerating in someones larger frame of reference. This would explain the feelings we get of years going by faster and faster. No I don't do drugs. I just think. Imagine our "outer space" along with all of our neighborhood stars and galaxies moving through a larger space? What are the odds that we are moving along at a steady rate? I say slim to none.

I always found it cool that by the same token, the faster you travel, relative to the speed of light, the slower your timespace goes. If you travel at high speeds for a while, and then come back to compare watches with a buddy that just sat on the couch, your watch would be set back from his. This has been proven via orbiting astronauts. If you travel at the speed of light, your watch stops. Faster Z makes you live longer relative to other slower people!

Based on this thread and speaking with others that have used the OBX, I ordered one. I will be putting it into my 280Z R200 next week. I will report on the installation process when I get to it.