JMortensen

I had a friend with a diesel rabbit who had a sign that said F*** YOU!!! and when he was inevitably cut off he would grab it and shove it up against the window. He was also 6'5" and about 280 had a beard and a pony tail down to his butt, so when it did come down to getting out of the car, that's all he had to do. He got out, they got back in their car and drove away. He's lucky though, because in truth I coulda kicked his butt, and I'm not a tough guy at all. He was a very imposing looking wussy though... Personally though, I just quit my damn job and started my own biz so I can work from home. You have never experienced quite such an infuriating thing as driving in Seattle. Sure there are a lot of cars, but there is just enough room on the road so that everyone SHOULD be able to keep moving. But they don't, because they're morons. AAAAAAAAARRRRRGGH!!! :twak: I think that's why my project has been moving so slowly. It's not even fun to drive around this poophole. Stupid idiots don't turn left on yellow. They merge with the brake. They drive the same speed as the slow jackass next to them on two lane roads. The semis drive in the fast lane on the freeway. The left turn lanes at stoplights are good for about 10 cars, and usually the first car takes about 7 seconds to get through the intersection, then the ones behind hit the brakes as they get to the intersection, cause hey, you wouldn't want to go around a turn at 20 mph! Did I mention AAAAAAAAAAAAAAAAAAAAAAAAAAARRRRRRRRRRRRRRRRRRRRGH!!! Yeah, so my answer is stay home...

That makes more sense... thanks.

I'm missing something. If the block would be 19mm taller, then presumaby the plate would also be 19mm tall. How are the piston rings going to pass over from the block to the plate. Seems like a recipe for ring failure. I don't think you'd want a piston with 20mm height to the first ring either, since you'd then have a really low pin height on that piston, which is also something to be avoided. What am I missing? Jon

They aren't approved for racing.

Yeah, the STOCK ones like a Toyota Camry or a Honda Accord. SHO-Z was talking about hot rod "Attack Honda" body kits and such.

I'd rather adjust camber on top and caster at the TC rod. That way you get more fine tuning of both.

I've never really noticed what people do with those huge holes on the sides, but this guy stuck a bumper on to cover it up. I always thought that was a sweet kit (only seen 2 in person, both very cool looking race cars), but it seems to me you'd want the front fender vented and the rear not, and the kit looks to be built the other way around...

I gotta go with the Mosler Twinstar. You can take down most Ferraris in a 6000 lb Caddy, at least in a straight line...

Try http://www.behrents.com. They had the best prices on everything except the calipers as I recall.

It's gotta be 87-89 turbo and not the SE model, which has a viscous LSD that won't work with your CVs. The SE models were pearl white with white wheels, so they should be easy to spot.

Those pics are GREAT Drax. I think it makes the whole thing easier to talk about. Thanks. You've made my point beautifully. The case does wear, and the LSD does require adjustment because of it. The aggressiveness of the LSD is based on how hard the gears rub on the inside of the case. Nodular iron will wear out too, as you pointed out. As to the lifetime warranty, that wasn't offered on any of the gear driven types I used to sell (the only one I can recall off the top of my head was the 2 year warranty on Tru Traks). Maybe Quaife has come up with a different material, or maybe they just factor the occasional replacement cost into the original sale price. Maybe it's like warrantying a Tokico or KYB strut. Sure the warranty is there, but how many people are smart enough to figure out that they even have a blown strut? Even if it's worn it's still going to be better than an open diff for a LONG time. Or the car changes hands and the warranty is no longer valid, can't find the original receipt, etc.

I'd keep the stock engine and swap it in every two years if mine needed smog... it's a bitch, but what other option is there? Not gonna keep it stock...

I absolutely love the current hard top version.

So where is the fuse??? Seriously, if I'm reading your description and looking at the picture right it sounds like the bearings have more to do with the side gears than the helical gears. The helical gears are what create the friction and limit the slip. That is weird though, it's the first time I've seen side gears with a bearing under the thrust washer, and I'm still not sure what the function of the bushing in the center is. Maybe the side gears move A LOT, and the bearing prevents them from binding and wearing into the case and the bushing prevents them from grinding on each other in the center???

That makes two of us, and I ain't gonna at that price!!!

I don't care if it's exchange rates, or labor prices or what, if I have to pay 3 times the value of any part, I'm not likely to buy it. There are plenty of quality LSD manufacturers here that could make an equal or better unit cheaper, there is just not enough demand. I'd love to have a Dana or an Eaton or a Trac-Tech positraction. Seems that those crazy bastards running those businesses would rather make 50,000 8.5 GM LSD's than 500 Nissan ones. That's where you and I disagree. I think that auto parts have a value that is not dictated by its country of manufacture, but rather by how good they are. So if there is no value gained I won't pay $50 for an Icelandic roll pin or $100 for a Siberian radiator cap, or $90 for a Ecuadorian ignition coil, or $1500 for a British LSD.

Truth be told if they were $450 and the clutch type was $500, I'd spring for the clutch type. I wasn't aware that we were getting such a "bargain". I also want cheaper gas, BTW. Maybe that's crazy too, since you pay 3 times as much for it. Doesn't make me willing to pay more. Makes me want to buy something else. I'm not after a $25K OS Giken head either... Exactly. RCNSC--relax dude. We're just arguing. No one should be getting their feelings hurt here, or getting uptight at all.

Drax, I don't know what Torsen diffs you were looking at, but you've got me confused as to how the ones that you opened up worked. You've got side gears with helical sections on the inboard side. The helical sections drive 3 long rotini pasta looking gears which sit in the middle. As you put power to the diff, the side gears want to move laterally before they actually drive the axles. When they move they drive the long gears against the inside of the case. Once they are up against the case and they cannot move anymore, then differentiation can take place. When it does take place the inside wheel must overcome the friction created by the gears rubbing against the case. The preload would be set by adjusting the side gear spacing so that the long gears are already engaged against the case. Without the preload the units spin VERY easily, at least the ones I've played with. Not sure how the TBR is adjusted other than jamming the gears against the case harder. As I said before, I know that the Gold Trak had different helical gears you could install with different pitched teeth. I assumed that this meant that they would try to walk off of the side gears quicker and hit the case harder. I've never seen the needle bearings you're referring to, so I don't know what to say about that. Seems counterproductive to the way the thing works to put a bearing on there. EDIT--Maybe the bearing is there to keep the noise to a minimum? I know the Tru-Traks are noisy, especially when changing from right hand turns to left hand turns and vice versa, like in a slalom. They make all sorts of creaking and popping noises as the helical gears get driven into the case and then overcome that friction and start turning.

That's impressive. Preload is the same thing you're adjusting in a clutch type by changing the thickness of the clutch pack, and you adjust it because of wear. But I ALWAYS hear the Quaiffe proponents talking about how it never wears, and never needs adjusting!!! Friction comes from work in the case of the ring and pinion or transmission gears, this is true. But when you are spreading the gears against the case to create the resistance instead of using the weight of the vehicle as in the ring and pinion or trans I have a harder time seeing how it is the meshing of the gears that creates the heat in the Quaiffe. There is no friction surface to increase the friction at the gear tips, so any increased friction comes from the tip of the gear digging into the case, which seems like it would be the primary heat generator. That's true, I've had my clutch style slip going into my old severely slanted driveway. But the one engineer I know who really turned me off on the Quaiffe kept breaking axles on his Midget, and didn't break them anymore when he went back to a clutch type. When I first became aware of them, I asked on the IZCC list, and several people who had switched to it had already broken stub axles. What that is worth, I don't know. Which sounds the same to me as having a worn out clutch type. Too little preload and it "goes open" and the inside tire spins. I don't see the difference. OK, so you can tune around it. I'm sure you could do the same with a worn out clutch type. If the inside tire never got light it due to less rear roll stiffness, it would be less likely to "go open" too. Also very impressive, and if it did fail they'd replace it, even if you were racing. I can't argue with that. Not sure I'm on board with this one yet. That part sounds good, except I like my car setup west coast style. About $1000 too much IMO. John's car is the fastest Z I've ever heard of, and he uses the Quaiffe. That says something for their performance. All I'm saying is that the gear units DO wear, they DO require adjustment, they do "go open" and they do cost too much. IMHO. The other question for me is that if the gear driven units are so wonderful, why are they widely considered the cheap crappy option for domestic racers? Maybe there is a design difference that makes the Quaiffe superior to the Torsen or the Tru-Trak. I can't see anything obvious in the exploded views.

How about "cubic bucks beats cubic inches"

RCNSC--have you seen the California Z kit? What you've done kinda reminds me of that kit. Looks good! I like that hood idea. Always wanted to vent my hood like that, even before I saw Terry's car. The only issue I would have is why have the back of the fender vented in front of the door and also have a big vent in the side. Seems like the side vent is unneccessary. Regardless, you need to start playing around with fiberglass!

I'd always heard they used the gear type. Plus, it's hard to equate anything we're buying for a couple hundred bucks to something in an F1 car. My experience has been that with one wheel off the ground you can spin the lifted side tire with one finger. In fact, this is the circle track cheater diff because it acts really open until you put power to it, so you can get through tech and they'll think it is open. I sold quite a few to dirt trackers for just that reason. I suppose you could adjust the TBR by shimming, but then you're going to wear the case that much faster. Ford had a different (possibly better) way of adjusting the bias on their Gold-Trak (I think?) with a differently cut set of helical gears. They were cut at a different pitch for different ratios. The Tru-Traks that I've seen have a block with a bolt and it's been a while, but I think they pull the side gears together or push them farther apart to adjust.

Auburns don't wear out clutches, they wear out the case itself. Kinda like the gear driven LSDs. They are not rebuildable, so as they wear they get less effective and eventually you just take them out and throw them away. They also chatter really bad, especially the Pro series. Viscous is reactive, not active. I've never heard a serious racer say they wanted to install a viscous LSD. I've heard people talk about changing the fluid to make it more aggressive. Maybe I just wasn't informed... I'll stick with my torque sensitive clutch style LSD, myself. Never heard that complaint about them not holding 300 ft lbs before. Good thing I don't make that much torque... Jon

The Quaiffe is a gear driven unit. People think that there is some magical gear in there that doesn't want to turn, and that's what limits the slip. This is just not the case. I'm more familiar with the Torsen, I've had a few apart, so I'm going to use that as my example. The way it works is the spider gears spread 3 long helical gears against the inside of the case. These gears need to turn in order for the wheel speed to differentiate, so they are forced to turn while rubbing on the side of the case. So the friction of the "toe" of the helical gears against the case is what limits the slip. You can "adjust" the preload by using a bolt to spread the gears against the case. Problems with this diff are: 1. They DO wear out. 2. They DO need to be readjusted from time to time. 3. They generate LOTS of heat since there is no friction surface, just metal on metal. 4. When a tire comes off the ground the gear type will transfer ALL of the power to that wheel instantaneously, in a Z this is bad because when that wheel comes down you've now broken a stub axle. Clutch style doesn't do that. 5. They slip! John Coffey has said on a few occasions that he's had problems with them slipping in high speed corners. He's also said that Quaiffe couldn't fix them. He did have another place to send them to that could get them to not slip anymore (EMI?) I've heard this same complaint from other racers now too. 6. Although I have to admit I haven't heard it in regards to the Quaiffe, I would estimate that I used to get 15-20 calls PER WEEK from Camaro owners with gear driven units that had just done their best grenade impression when I was selling diff parts. When I worked for a diff parts supplier we sold hundreds of Eaton clutch style posis (the good one not the Gov-Lock POS that comes in GMs) to people who had destroyed their gear type LSDs, and we had 20 Zexel Torsens on the shelf priced at $135 and we couldn't get rid of them. That's right... $135!!! Why is the Quaiffe $1200 when a Torsen is $135? I don't know. I've looked at a diagram of the Quaiffe and they appear to be very similar. Even a Tru-Trac is only $350. Domestic clutch types are in the high $300 range just for price comparison. To me the only advantage to the Quaiffe is smoothness and its low breakaway pressure. With such a low breakaway it doesn't tend to affect the turn in as much as a clutch style LSD. And you can use it as a cheater diff if you're in a class of racing that doesn't allow LSD. The advantages of a clutch style are price, consistency, durability, adjustability, and rebuildability. I know I stand in the minority on this one, but I have enough experience to feel that my opinion is warranted. Jon