JMortensen

Yes, you have the pinion flange stuff correct now. I know if you want to run U-joints, you can grab the side yokes off of your existing R200. I've done that much myself. I THINK if you want to run the CV's that the CV shafts have the side yoke part built in, so you would need both CV shafts and to bolt them to the stub axle on the wheel end, you would need the companion flange. I'm not sure if you need the stub axle AND the companion flange. I'll leave that question to someone else. Good luck with the project! Jon

I still think you're looking at the sides of the differential. I'm talking about the front of the diff where the driveshaft bolts to. There is a circular flange, some call it a yoke, some a flange, that bolts to the pinion shaft. You need to switch the pinion flange or yoke, whichever you prefer to call it. Jon

I'm not talking about the driveshaft at all. I'm talking about the yoke on the diff. The huge nut in the front of the diff holds it on. You need to take that huge nut off, pull the yoke, put it on the new diff, and put the nut back on. Lots of people will replace this nut, but I think it's OK to reuse if you torque it down hard and use loctite. I don't know the proper torque spec, but as I was informed here a couple of months ago, there is no crush sleeve in the Nissan diffs so find the right torque, hit the nut with that torque and it should be good to go. Jon

Yoke or pinion flange for the 280 driveshaft. The 300 driveshaft has a different bolt pattern. Your old one should work. Just swap them out and torque the pin nut down really tight, use a little red loctite on it. Jon

Well I am soon to be a member of Jack Stand racing I think... I've got a bunch of stuff to do to my car. I'm definitely doing this, but you all probably won't get a report from me until spring. Also, looks like I am changing out my MSA header for a Nissan Comp unit, so I probably won't have anything like verifiable results... Jon

I think that little rubber just keeps the spring from rattling. If you are going to make your own pillow ball mounts, this may help: http://sth2.com/Z-car/shocks.htm At least it may give you some ideas. Jon

Duh. Thanks for pointing out my contradictory argument. Feeling a little stupid here... The few people I've talked to that have done this have said that it works, but they have claimed 20hp. I am not expecting to get that big an improvement, my gut tells me that is a little unrealistic. I agree that this is better than routing to the intake, since you aren't sending crankcase fumes and oily crap back into the intake manifold. Especially in a case like mine when running triples, where it is a PITA to route the PCV to every runner on the manifold. Jon

Get a manual or do a search, the rear wheel bg thing has been discussed before. It's kind of hard to explain if you haven't seen it before. Cruez's idea is a good one to check too. You can check runout on the hub with a dial indicator, or take it to a shop that can do that for you. Jon

I'm guessing that BOZ moved the crossmember forward to lessen the amount of twist on the front control arm bushings. You would still need a longer TC rod if you were to move the crossmember. The stock "bucket" is pretty flexy, and if you already have an adjustable TC rod with a rod end, it should be really easy to make a stronger mount from 3/16" plate or similar. Be careful of getting the angle wrong on the mount, or you will twist the end of the TC rod where it bolts to the control arm when the suspension goes through it's travel. I would suggest that you only move the mount if you have rod ends on both the control arm and the TC rod, then you should make your bracket and tack it in place, then bolt everything up without the strut in, and make sure that the suspension doesn't bind when it goes through it's range of motion. If you already have adjustable TC rods, it kinda begs the question of why you don't just adjust caster with them. Even if you wanted to make a better mount, you could still leave it in the same place, and lengthen the TC rod to get the caster. HTH, Jon

OK, maybe it is the wheel bearing. Yes, that is the wheel weight I was talking about. I once had a situation where I did not realize that I had interference between the tie rod and the wheel weight, that's why I mentioned the weights, I thought maybe the weight was hitting your brakes or something. The rear wheel bearings are not fun to replace. Make sure you cut the peened area of the nut on the back of the stub axle ALL THE WAY OFF before you remove it. Possibly upgrade to the 280ZXT nuts to reassemble. Jon

On the camber plates there is a monoball at the top which allows for the strut angle to change relative to the strut tops. I thought that the rubber performed this function in the stock unit. There is a bearing in there, but I don't think it pivots IIRC. I think if you take the rubber out you will have massive suspension bind because the top won't pivot in relation to the strut. Something has to give... This is all from memory, so I could be wrong. Just check and see if the bearing in there pivots to allow the strut angle to change. Jon

Usually a wheel bearing noise will change under side load. Go down a street and swerve hard side to side, and you should hear the noise change. Generally wheel bearing noise is a groaning type of noise. Did you pull the wheel off? Maybe you've got a wheel weight coming off or something. It doesn't sound like a wheel bearing from your description. I'd check the brakes too. Jon

I seem to vaguely remember a science project in 8th grade or so where we took a straw in a glass of water, and blew past the end of the straw with compressed air, and watched the water go up. I can't remember the name for it. I looked a bit on the internet, and the only effect I could find that I thought was even remotely similar was siphoning, but I don't think that that is the correct term for why this works. It's like the gas in a carb though. Think about your old SU's. Was there enough engine vacuum when you were driving to suck the gas out of the nozzles? If you stopped the air flow, and just put those carbs in a case filled with vacuum, would the gas fly out of them? No. What pulls the gas out of the nozzles is the air rushing by them and into the motor. There is no vacuum in your exhaust. There is velocity in the exhaust gas. It's counterintuitive, but this idea does work. I'm done trying to convince though. I'm just going to do it and let you all know what I think when its done. Probably have an update on that for everyone in the spring time when I drive the Z again. Jon

Regardless of whether there is another piston going up, can we all agree that there is pressure in a crankcase? Can we all agree that it gets higher with rpms? I would think so. Anybody else ever seen a Volvo 4 cyl in a 240 or 740 with the PCV plugged? It blows oil out the valve cover, oil cap, and anywhere else there is a gasket or seal. How about a newbie hot rodder that plugs all the PCV ports because he wants to eliminate all that smog stuff. Fire it up and it leaks immediately. With this in mind, when the piston goes down, it is still compressing the air underneath it, and that air is pressurized. It may be less pressurized because of another piston going up, but it is still pressurized. And there is still the issue of wind resistance that putting vacuum to the case would alleviate. Jon

It creates power because there is no air resistance in the crankcase. That's why I brought up the example of mile high stadium. Isn't it Sleeper that lives in Denver? What's the air pressure at 5000 ft Sleeper? Isn't it something like 12lb/in vs 14 at sea level (guessing here). And that 2lb/in means that the ball travels farther with the same effort. Less energy or hp in our case wasted to push the ball or engine internals through the air. Here's a totally different example. They say that open wheel cars use 80% of their hp in just pushing the car through the air. Take that same car and put it in a vaccum, and what's the new top speed? It's gonna be way higher. Because the resistance is not there. Take that same car and put it in a track that's inside a huge hyperbaric (sp?) chamber that's at 3 bar pressure. Top speed is going to be seriously reduced (assuming the engine isn't getting that 2 bar boost!!!). In the engine we're not talking about top speed, but the resistance to movement created by the air pressure inside the crankcase. Someone mentioned routing the PCV to a vacuum source. Only problem there is that you don't have any vacuum at WOT, or a lot less anyway, and that's on an N/A engine. So at the time when you have the most crankcase pressure, you have the least amount of vacuum trying to suck it out. But if you use the exhaust you would have more vacuum at higher RPM's, which is when you need it. But the crankcase is filling with blowby and air pressure is generated just from the crank spinning and pistons going up and down. This I think is the important part. When the piston goes down and there is pressure in the crankcase, it is forced to compress on the DOWNSTROKE as well, even if it is to a much lesser extent. Someone else mentioned hooking up a vacuum pump to the PCV. I suppose that might work, but the expense involved would be a lot more than the kit at Jegs, for sure. I imagine it would have to be a pretty big pump too to move enough volume to evacuate the crankcase. I haven't seen anyone else's setup (I wish I could though). The GN story made me think that hooking all of the PCV ports to the vacuum source may be a bit much. I'm thinking now of putting a filter on the pipe coming out of the PCV on the block, then hooking to the valve cover. If you felt like this was too large a hole, you could always put a restrictor inside the filter to get more vacuum and less fresh air coming through. Jon

I have had a wheel spacer fail, and I have heard of one other failing. That being said, I wouldn't hesitate to use them, and have some on my Z right now. The reason for the failure in my case, and I suspect in both cases, was the failure to check that the wheel spacer fit properly. Both were Mr Gasket cheesy auto parts store spacers, and mine failed because the inside hole was about .005" too small. It looked as if it sat flat against the hub, but in fact it was tweaked between the hub and the wheel. I fought what I thought was a tire balance problem for over a year. I couldn't figure it out, neither could the tire shops and alignment shops I took the car to, neither could any of my racer/mechanic buddies. I finally figured it out when the spacer cracked. It didn't fall out luckily for me, just cracked. I replaced them with a set of billet spacers from Coleman, and machined the front spacers so that they were lug centered, not hub centered. For this reason I recommend a lug centered spacer and not a hub centric spacer, unless the hub centric is made for your car, and I mean FOR YOUR CAR, not for a Z, or a Mustang or whatever. IME as a Porsche wrench, I saw many factory and race modified Porsches running THICK spacers. None were bolt on, all were slip ons, and judging by the looks of the material all were cast aluminum. Never saw one fail. The only warning I would give with spacers is that you should have a GOOD set of wheel studs. Aside from that I've seen 500 hp roadrace 911's with 335/35/18 slicks not break a 1 1/2" spacer. Jon

I agree with Mat. No one complains when Aux posts pictures of women on mopeds with their helmets on backwards, or a Donald Duck ride. This is the non tech board. If you don't want to look at it, don't look at it. Jon

It's kinda funny Bastaad, but I've been rolling that one around in the back of my head for about 10 years or so, and I just found the kit on Jeg's website like 2 weeks ago. But the idea is sound, so don't let anyone talk you out of it for that reason. There may be other complications like the rear main thing, but the idea is a good one. Jon

I had an idea. Maybe leave the PCV vent open, with a filter on the tube, then route the vacuum off the valve cover. It might prevent the system from drawing too much vacuum, and still use the exhaust to at least reduce the pressure inside the crankcase. Still want to try this... Jon

You might want to consider the weight of a good wire wheel. Seems kinda backwards to put a really heavy wheel on then spend big $$$ for racy tires. All that rotating and unsprung weight isn't going to help your handling or performance. Jon

I suppose that depends on how you combine the two. Jon

The Z mechanic guy I talked to mounted it just after the collector. The higher the exhaust velocity the more suction, so the GN guy may have had too much vacuum. You would think that it would only suck oil if the PCV was really low on the block. Maybe it would be possible to get around that by plugging the block PCV and connecting to the top of the valve cover, which has that baffle built in. I can only assume that you'd still be able to pull the pressure out of the block, but I suppose it would have to be tried to see if it really worked. I know it works, drag racers have been doing it for many years. I just don't know how well it works, and I've always wanted to try it. Jon

The crankshaft is pushing around through pressurized air, which is harder to do than in a vacuum. Think of how many home runs you get at Mile High Stadium, and that's only a few in/lbs less pressure, not a vacuum. So if you run a vacuum in the crankcase, the internals can spin easier. In the How to Hotrod book they say not to put too much vacuum to the crankcase, because the rear main seal will start to suck in and create a huge oil leak. I know one Z mechanic who was claiming 20 hp on a really crazy NA buildup (don't know if I believe him), and I was considering trying this myself, and he said he never had a prob with the rear main. In fact, here's a kit: http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=1783&prmenbr=361 If you're serious about trying it, I'll go halvsies with you on it since theres 2 in the kit. I'll buy it and sell you the other half and we can split shipping. Only thing I would be concerned about in your case is the turbo. I don't know what effect that has on this. Jon

I've always loved that green... Jon

http://auto.howstuffworks.com/differential.htm They've got 'em all. Jon