JMortensen

There was a thread about places to buy metal just a couple weeks ago, so look for that. This one is close to my house but apparently are pretty well known. http://www.onlinemetals.com

If that's mountain bike stuff you're talking about, then it sounds pretty similar to what we have here in the NW. Single track through the trees pretty much everywhere. Take off the big chainring and put on a bashguard if its the same as around here. You'll almost never break 20 mph, but there are tons of log crossings everywhere. This kind of riding is really fun though. I think I enjoy it more than the big fire roads I used to ride on in CA. I like the technical stuff even if I'm not super good at it and it's more of a challenge and more fun to have to get up a short climb with tree roots sticking out of the ground at weird angles than to climb a wide fire road with decomposed granite that just never ends. Downside is hugging trees like I did a couple years back. Smacked my head good on an endo into a tree and lost a full 3 days memory and had no and then just a little short term memory for about a month. Look out for jumps that seem tempting but land near trees...

I was at the concert at the Rose Bowl in 94. It was one of the best shows I've seen, even though the LA Times panned it in a review. I wonder if it would be as good on video though, seems like tryint to take photos of the Grand Canyon. At the Rose Bowl the sound was pretty insane. When they did Us and Them, the "Us, us, us, us, us, and them, them, them, them, them, them" was coming from different speakers all around the stadium. I expect the contact high probably helped make that effect that much more intense. It was pretty wild. The lights were fairly bitchin too, and they had giant pigs that came out of the sides of the stage and bounced up and down, then fell off at the end of one of the Animals songs. I've had the Pulse CD for 10 years, so I'm kind of surprised that they're just now releasing the DVD.

That's good news, thanks. What did you think about the gusseting info on that other page? I was curious to hear your take on that subject John.

Just ran a tape measure down the side of the car, and it looks as though you'd need about 9' of tubing to run it all the way down the rocker. Got me thinking about weight and strength. Correct me if I'm wrong in any of this, but I show: rectangle 3x1x.065 = 1.7146 lbs/ft so *9 = 15.4314 lbs 3x1x.120 = 3.0754 lbs/ft *9 = 27.6786 lbs square 2.5x2.5x.120 = 3.05 lbs/ft *9 = 27.45lbs round 1.75x.120 = 2.089 lbs/ft * 9 = 18.801 lbs 1.625x.065 = 1.0818 lbs/ft *9 = 9.7362 lbs 1.5x.095 = 1.426 lbs/ft *9 = 12.834 lbs So these are some materials that people might use to do this rocker reinforcement. I have some vague notions of strength which I'd like to put forth, hopefully if they're wrong someone will let me know. Rectangular tubing is stiffer in bending than round. Round tube is stiffer torsionally than square. DOM is stronger than ERW. Rectangular is usually (always?) ERW, but round DOM is easily found. What I don't know is which tube is the better choice for this project. Looks like you can get out of it for a pretty minimal weight penalty by going with round thin walled tubing, but the question is what strength is actually required here? Is it better to carry the extra 30 lbs, or the 9 lbs? How would the strength of the rocker compare if one uses a flanged hole section of of sheet to connect the round tube to the rocker like Mikelly did on his A pillar: http://pg.photos.yahoo.com/ph/dat74z/detail?.dir=fb30&.dnm=2465.jpg&.src=ph The one other thing I want to check is clearance to the seat. I think in my particular case that the 1x3 might just interfere with the seat sliders. Just something else to consider.

Top End Performance makes the strut tower bars, apparently they did most/all of the work on the car. http://www.racetep.com Search for them too, lots of opinions on them around here.

My bar is 1.75 x .120. I did that because the SCCA rulebook says 1.75 x .095 in one place, then in an addendum it says 1.75 x .120. I think that most guys who run 1.75 are running .095, but I just wanted to be on the safe side, and if the regulations change again I'll still be OK. If you look at this picture, from underneath, you can see that the frame rail ends before the rocker, so no, my bar doesn't attach directly to that frame rail. I had been trying to figure out a way to strengthen this area, and I think if I ran a small tube diagonally from the end of the frame rail to the rocker area that might just do it. Maybe just a simple gusset in the corner there. As it is the cage attaches to the rocker, and the wheel well, which is connected to that rail, but they are not connected directly.

I did my rollbar similarly where it attaches to the rockers instead of a box on the floor (see pics). If I end up going with the full cage, my thought was to put in a "door bar" that is right on top of the rocker, and then attach with gussets to the rocker all the way down it's length. I think attaching the cage to the rockers gives the cage a better, stronger attachment point, but I don't know how much it does to strengthen the rocker.

Yep.

I wish I had thought of strengthening the rockers before I welded in my roll bar. In retrospect I think the rockers are more important than the SFCs. Just think, with the rocker design, Nissan put full tubular frames down both sides of the car and they attach in right at major structural spots in the front and rear. They stopped the floor rail before it got connected to the rear. It's obvious which one they thought was more important. 2.5" tubing on the SFCs is major overkill IMO. Good for front frame rails. Way overkill on the SFCs.

I'm not sure on the 280, but on the 240 there is a rear frame rail right inside the rear valance. It's not very big, but it is definitely stronger than the 240 bumper. I would assume that yours is the same. Having been rear ended in a 240Z by a newer Firebird going ~50 mph to my 0 mph, I can say that it isn't fun, but the passenger compartment actually survived the hit very well and believe it or not the gas tank didn't rupture or anything like that. The rear end frame crumpled in about to the rear strut tower though.

I was looking for a calculator to tell me how much tubing of a particular wall thickness would weigh per foot. I found this site: http://www.thefont.pwp.blueyonder.co.uk/bikes/index.htm which appears to be a DIY chopper site out of Europe. The calculator on the "Selecting Tube Sizes" page seems to work, and he gives a good demonstration of bending stiffness. I thought the page about gusseting was pretty interesting as well. I was planning on gusseting my roll bar the "wrong" way with the gusset right in the middle of the tube. At least wrong according to his article. Now I'm thinking I should do it tangentially. Anyway, I'm hoping this might spark a conversation about how to gusset and maybe tubing length and thickness as well. The guy seems to know his stuff. Heres the jacking my own thread part - My own interest in this has to do with adding onto my roll bar, and I was considering using different size tubing for the brace parts which aren't part of the traditional 6 or 8 point cage. I used 1.75 x .120 for the main hoop, and was considering 1.625 x .065 for the bracing, but could get 1.75 x .065 if necessary at about 4 times the cost of the 1.625. Still don't know what to think about those options. In reading katman's ITS article it says in a parenthetical note: However when I read the SCCA rulebook I can't seem to find any reference to cage tubing sizes other than for the basic 6 point cage and the shoulder bar. Maybe that rule has gone by the wayside, or maybe since the ITS rules don't allow the bracing that I'm going to do, they just don't have anything to say about this type of bracing. I really don't know. My car will be an autoxer and time trialer, maybe at some point might be entered in a vintage race or two. The added structure will be bracing to the front and rear strut towers, maybe down to the subframe connectors, that type of thing.

That's exactly what I was thinking. Someone has been playing a bit too much Gran Turismo or something...

I didn't really think of it, but when I was welding on the rails I was welding thicker metal to them so I would have had my settings a bit higher.

If you had a stock cam you probably would have been in the 210 range. Your bigger cam lowers the numbers for the compression test. As long as they're all even you should be fine. As for your performance at the drag strip, that does sound pretty bad. I looked it up online, and stock was apparently 16.9 according to this page: http://www.albeedigital.com/supercoupe/articles/0-60times.html so you were almost a second faster. Have you drag raced before? Might be that it just comes down to the 16.9 being done by a pro who drag races all the time vs a first timer. I'm not a drag racer, but in my kind of racing the driver makes all the difference. IIRC the ZXs with the T-tops had 3.90 gears, and the ones without had 3.54's. I'm not positive on that, so double check me, but if that is the case the 3.90 gears would certainly help with the long 3rd gear feeling.

Not sure what you mean. If you get the .065 tube and set it up to weld the tube nicely you should do OK.

The rails aren't too thick. I'd get thin 1x1 tubing, no point in having .120 wall tubing to hold up a cell that probably won't exceed 120 lbs full. I'd use a 1x1x.065 tube in front and back, then use straps underneath. That's my plan when I get to it. I don't know what kind of welder you're using but I've been using Amp setting of 5 and wire speed of 4 on my MM135 when I've welded to or around the rails. Haven't had any trouble burning through, but it's clear that the penetration was good.

If #248 was really in good shape then it would be worth more than #25764, but what you've got there looks like it would take a pretty good effort (financial too) to get it back on the road even in stock form, then those same purists who talk about how much these cars are worth will be bitching about the originality of the car or condition or whatever else they can come up with. It's been my experience that there is a lot of TALK about how much these cars are worth, but my friend sold #472 maybe two years ago and after a bunch of hassle I think she got $7500 or so for it. It was really a solid car, needed some TLC, but I thought for sure based on threads I'd seen on classiczcars.com and IZCC that it was going to go for $15K. Had another friend try to sell #12xx and some purist jackass drove 6 hours, then picked it to pieces based on condition and offered $1000 (I think the asking price was $2500) and complained that because he had driven so far he should get a deal. My friend told him no way in hell, and he sold that car to a 17 year old kid the next weekend. Another one: I had an ebay auction for a smog rail a while back. Thing was brand new, never installed. The person who bought it complained about the condition of the zinc coating on the part. I kid you not. This part just sat in a box for 5 years then went up on ebay, and we all know what they end up looking like when the car has been driven. Apparently her idea of how to enjoy a car is to never ever start it up for fear of damaging the zinc coating on the friggin smog rail. Either that or she's going to be really upset once the thing has run for a couple hours. IME, purist = *******, and despite what they say none of them actually wants to fork over any cash, they just talk a big game. So hybridize away is my advice, although I think it's safe to say that I'm a bit jaded at this point. It's your car, do what YOU want to do with it.

Ross has a day job and does the modern motorsports thing on the side. The Z performance market isn't very big, so we should really be glad people like him do this at all. The other guy is Mike Gibson, and he used to have a link to Z and 510 racing parts off of the http://www.fonebooth.com website, I don't see it there anymore. I think his username here is scca, and I think he still pops up from time to time. Might try PM'ing him.

I believe there are some easy fixes for this, I think http://www.modern-motorsports.com sells a little adapter that will fit your cable end and the clevis on the ZX brakes. I think the fonebooth guy Mike sells them too. On my own car I used a 240SX ebrake cable. It was $10 out of the local JY and it was pretty easy to install. I removed the rear bell crank and ran the cable all the way up to the ebrake handle. It has some mounts that are integral to the cable housings, so I just pushed them up against the floor and bolted them on wherever they were out of the way. Worked great for years, then I finally took the ZX brakes off and sold all that stuff, My new new brakes won't have an ebrake function.

Correct. You won't be able to move the car with the engine with a broken halfshaft. You could if you had a Detroit Locker or a spool, but not with an open or LSD.

According to post #48 on this thread: http://forums.hybridz.org/showthread.php?t=106354&page=3 the Carreras are NLA. I'd be really tempted to try the Bilsteins without a revalve at those spring rates. If that doesn't float your boat you could do the old standard Tokico Blue or Illuminas. Regardless, that thread should help a LOT. Great info in there.

I never fully understood how that worked. All I know is it is supposed to be more rigid, and I loved the bilsteins I had on my other vehicles, although that probably had more to do with valving than the pistons. Theoretically if more of the weight was up top than the sprung weight would be increased, and the unsprung weight would be reduced.

Yeah, but the piston is twice as big. Unless the threaded section is aluminum I don't see weight savings being a real factor.