JMortensen

I'm not sure that is right. I read the SR20 forum post as saying "If you have an open diff, you need the VLSD shafts to work with the HLSD". I know that the VLSD has a higher spline count, but I don't know what it is. I thought the open diff had a 29 spline shaft and the VLSD was a 30, but I'm not positive on that.

That means the one that I linked to is no longer legal either. Don't know how much that matters seing as how he said legality isn't an issue for him. The similarity I was referring to was in the main hoop and then a smaller cowl height dash "hoop" that gets tied together with door bars and then through to the struts.

My 240Z has them. Not sure about the 280 though.

I'm still in the beginning stages of building my very first roll cage, so I'm no expert. I am trying really hard to think it through though... This might help. This the guy who bent my hoop for my cage. His Miata cage may give you a few ideas: http://www.chaserace.com/cage/cage.html

Not to mention the factory ones have the half moon shape on one side so that you can tighten from the nut side without having to hold the bolt

Well I was kind of taking that information from this part of the thread on the other forum: That seems to back my statement up, but I don't know how reliable the info is from the other site, so someone is going to have to be the guinea pig...

I believe that the 88 SS shafts for the VLSD will work with that HLSD. I know they're larger diameter shafts with a greater spline count. I think since they're Z31T shafts that modern motorsport's CV adapters will work. This thread has related info: http://www.sr20forum.com/showthread.php?t=169151 EDIT-- I see you are correct, it does look like the GKN diff, not like the older Torsen.

That link shows more of a Quaife design than the Torsen design used previously in the R200. The Torsen that they used to make for the R200 looks like this: I'd be interested to see one of the S15 diffs with the cover off...

The turbo tranny is geared lower, at least in the first three gears. It has a much wider spread between the gears than the ZX transmission. Strength is great and all, but the close ratios of the ZX box would be my preference for a NA car. This should help... http://www.geocities.com/z_design_studio/ Tom is right about searching too. This is old ground we're covering here...

Because the 280Z rear strut towers are taller and in a different location than the 240Z rear towers.

Did he mention what about the motorcycle carbs makes them more efficient? I have to imagine the sound is going to be pretty similar. 6 open holes through which you can see the intake valve either way. Not trying to bust anyone's chops, just would like to know if there is REALLY a difference, or if it just looks cool. I do think it looks cool, for what it's worth.

A cage done this way would actually be pretty similar to what you would find in a convertible race car that doesn't run a windshield (most of them), so shouldn't be giving up too much in terms of rollover protection. Usually the convertibles have a Petty bar which probably wouldn't be a good idea here if you wanted to carry passengers, but other than that should be pretty similar...

I'd take a good long look at 74_5.0L_Z's cage. He has a roll bar but no bars in front of the seat at the roofline around his head, then door bars which connect to a dash bar and that goes out to his tube frame front end. If you ignore the tube frame front end and consider running some bars from the dash bar out to the strut towers, then you'd have pretty much all of your requirements. No bars to smack your head on, significantly stiffer chassis, fairly easy to get in and out of. http://album.hybridz.org/showgallery.php?cat=500&ppuser=7833

I wanted to make the point about installing it the right way, but I suppose you're right.

I'd like to see a whale tail in there too, and you didn't mention the vortex generators. Pretty damn cool project though. I think the tough thing is going to be getting everything switched out quickly. Maybe swap the entire hatch out to change the rear spoilers. The front is going to be the interesting part. If you have time, and you might not, I'd like to see what exactly the difference is between having the huge hole in front of the airdam vs having it sealed up with aluminum like the car in your sig pic.

The newer S15 supposedly also uses that same HLSD.

Shouldn't be any harder to tune, what would be a bitch would be synchronizing them all, but even that shouldn't be too hard. As long as the linkage was solid it would be 1.5x as hard as a motorcycle.

What looks "not strong" about them? Looks like a hell of an improvement over the straight bar to me...

Add another. Do the figure 8's. When it works its way in the chatter should go away. If it doesn't, add another tube. I can't remember any diff taking more than 3 to stop chattering, so I'd imagine that should do it for you. Might ask bjhines too, he's been running the more aggressive one like you've got, so he might have some insight into how much additive you need.

Um, yeah it is...

Are you using any LSD additive? You MUST use LSD additive with these Power Brutes. You can get it from any auto parts store. They have different types, Chrysler, GM, Ford, but it's all the same stuff. I'd buy two tubes of the stuff, put one in and find a parking lot and do some figure 8's. If it doesn't go away, add the 2nd tube. Don't worry, it'll be fine.

In the future posts about parts for sale should go in the classified section. I know that there were some problems, but it appears that SuperDan has resolved them, so that is again the appropriate place to sell your wares. We'll let this one run its course.

Is there supposed to be an advantage over traditional Mikunis?

Added info on stub axle failure, spider gear failure, and Phantom Grip LSD. I could NOT find pictures of the cross pin shaft bent and broken. If anyone has pictures of that and doesn't mind, let me know!

Good point. I think I know where I might find some pics too... might be a day or two. In the meantime I added more stub axle info and some pics from http://www.zparts.com