Zed Head

Figuring out how the loads get distributed can be hard to do. Under lateral loads, like cornering, you could imagine that the highest loads are at the two inner attachment points of the control arm (transverse link in Datsun-speak), Which transfers in to the links that drop down from the body, and the diff mount/crossmember. The top of the strut only sees the weight of the car, essentially, as you describe, in-line. At first glance, it looks like the tops of the towers are important load-transfer points of a triangular structure. But because of the shocks and springs, and the flexible hinge at the hub, they really only see changes in "weight" of the car. It's interesting to look at because you can imagine a much weaker strut tube than is used. The double wall nature of the strut tube with a shock tube inside is really much stronger than it needs to be. So it leaves up-and-down as the force at the top of the tower, coming from the suspension. Which should really only be unusually high if you bottom out the shocks. So, in travelling over uneven bumps like a driveway entrance, you're probably really combating flex from twisting of the whole metal box/body. Which seems to me like it would a blend of fore and aft, and lateral, a diagonal flex. My 280 creaks the most when a front and rear wheel on opposite sides (diagonal) are unloaded at the same time. Like a driveway entrance. That's just one pass through the brain. Something new pops up every time I think about it.

This gets discussed quite a bit on various forums. To John C's point, the towers are already braced for lateral motion,under the vinyl. To Mark M's point, maybe bracing forward and backward (what a roll cage would do in addition to lateral) would be more helpful. Also, the 240Z is known to be flimsier than the 280Z so what helps on a 240 may not help so much on a 280. The use as a cargo barrier/holder though has obvious value. Maybe that's enough. It may also help in an accident, basically inert metal until needed. From what I've picked up, if I remember right, a triangular brace from the firewall to the front towers is the simplest bolt-on brace that you can add. It addresses fore and aft, and lateral, motion. Here's an example - http://www.racetep.com/zfront.html

Did you mean 280ZX 3.9 long-nose? That's the typical diff for the 280ZX. The 300ZX NA's came with 3.7, typical, and have a different flange pattern. More work, to swap the flange so a 280Z or 240Z propeller shaft can be used.

My understanding is that the main difference, and maybe the only one, is that the bottom portion of the automatic plate is removable so that the torque converter bolts can be installed and torqued. The plate is actually just a dust and water shield so that makes sense.

They're called "hog-rings" and they're the stiff pieces of wire crimped around the edges of the material and the wires and the springs to hold everything in place. Search hog-ring on the net and you'll find a bunch. They were/are crimped in to the noses of hogs so that they can be controlled. Actually, (edit, I'd forgotten) so they don't root around. They make different sizes for different noses, from little piggies to big hogs. How to ring a pig's nose (noise alert!) -

Actually, I was kind of lazy in my response. The ratios are listed for the 5 speed in the FSM. 5th is not direct. The "mysterious" 5 speed I was referring to is commonly called the direct-drive 5 speed dogleg "comp" box. Comp for competition. I think it was an option from Nissan at some time. Anyway, even if there was a list of codes for the transmissions, with the interchangeable parts you'd still have to do some calculations or open it up to know what you had. From the 1972 FSM. Note that the ratios do seem backward, compared to the ratios of the transmissions. The 5 speed needs the 3.9, and the 4 speed, the 3.36.

Is this the mysterious "dogleg" 5 speed, that sometimes has a flange on the output shaft? 1:1 (direct) 5th gear?

Kameari has a solution to avoid the little click, but their product is a little pricey. A handy person could probably copy the concept to modify the stock parts. http://www.kameariusa.com/l6-adjustable-timing-chain-tensioner/

Man, I really appreciate the way you keep going once you get started. I've had a few start at 10 am, WTF it's 1 am days myself. I hate to leave things undone. I didn't even know about the "little click" until now.

How about some of these - http://www.traxxion.com/Shock-Spring-Torrington-Bearing-Kit-by-Traxxion-Dynamics-0/ I don't think the people that designed the urethane bushings put a ton of design effort in to them. They're just stiffer and cheaper than the stock rubber parts. Same durometer urethane compound, a bunch of different shaped molds. Easy money.

Assistant associate watercock ****-a-doodle-doo Dickinson damnation Edited out a word - just in case. Although it looks like the software completely removes/changes the word once you save the post. Gone forever. Edit - looks like he's working on it. Sorry for the last word Mike, I was ready to edit it out.

Many people have tried to correlate the numbers on the transmissions with some basic qualities of the unit. But there doesn't seem to be any correlation, even though there are Nissan documents that show where the numbers are. But no charts indicating what the numbers mean. A 300ZX 5 speed will not fit correctly because the VG30E (V6) engine used a tilted bolt pattern. It will bolt up but it the shift lever will be at an angle.

The bolt patterns and centering/locating ring sizes are the same for the 240Z - 280ZX NA cars (non-FS5R90A transmission). Sometimes there is confusion about square versus round flanges but Nissan made both with the same pattern and size for the 280Z's. I have one of each. I also have differentials from 1976 up to 1983. I have a 1983 diff in my 1976 car with 1980 NA transmission right now, with a 1978 propeller shaft.The shape of the flange does NOT indicate the pattern and locating ring size. 300ZX's are different size but came with a square flange also. On the length: the propeller shaft lengths are shown in the PD (Propeller shaft and differential) chapters of the FSM's. I'd use those numbers over anybody's well-intentioned efforts with a tape measure. But for the cost of shortening a 280ZX propeller shaft you could probably find a 280Z shaft somewhere. Maybe even two or three. They last a long time.

Pretty cool. I wonder if the AFM that system used had the idle air bypass port. Goes to show another way for the cat-skinner. Has anybody ever seen a cat skin or a skinned cat? Who started that saying?

Some people are converting more modern systems to their old Z's. Make the car do what you want it to do.

You must be talking about the manual air vents. I've wondered about those. I have the AC system and all of the external air comes though the central heating/cooling system, through the cowl supply, described in the FSM chapter. I've never seen a good description of the vents with the manual pull knobs, which, I assume, only came with AC-delete cars. I have pondered adding them to my car, since the combinations offered with the AC system are kind of strange, with the Bilevel and the Fresh and the Defrost.

Are you using stock suspension bushings or aftermarket urethane? Looks like a fun car but the important details are sparse, re your problem. And springs don't care if they're upside down or downside up, it doesn't matter, unless the perches match the ends (which would be unusual). If you meant front to back backwards, that's a whole different thing, since they're different rates.

The Mallory is a complete distributor designed for the Mallory module. I don't think that points will drop in there. Or a Pertronix unit (now I see what you meant in your first post. I don't think that's an option). I may be wrong. The Pertronix is a points replacement product, used in the stock distributor. Points will drop back in there.

From certain angles a recent Mercedes seems to have some Z car design elements. http://commons.wikimedia.org/wiki/File:Mercedes-Benz_SLS_AMG_in_New_York_City.jpg And the new designs seem to be following the same path the Z car design did. http://www.telegraph.co.uk/cars/mercedes/amg-gt/

Also note that all of these old hot rod brands are now under the name of Accel Performance Group. They're just names now. Prestolite, Accel, Mallory, etc. Click through from a Mallory page and you'll end up on a variety of different pages with those names. Got carried away and found out the modules are out of stock also. So, basically, any parts you find are just leftover from the last big manufacturing run. If the demand is't high enough "out-of-stock" will change to "discontinued". They won't make any more. http://info.mallory-ignition.com/support/faq.html http://mallory-ignition.com/catalogsearch/result/?q=605+module (out-of-stock) http://mallory-ignition.com/catalogsearch/result/?q=6100m+module (out-of-stock)

You can't go wrong using the coil resistance specified for your 240Z and its ballast resistor. It will be an old "low energy" ignition system though. About the same overall effect as installing a Pertronix unit in the stock distributor. And you'll want to think about your timing advance curves, to get best performance. The Mallory site says MAL-4563901 is out-of-stock also. So if the module does get damaged, you may not be able to get replacement parts. More buzz-kill. It's a dilemma. There aren't many ways to spend your way up to higher quality any more. I get the idea but, from what I see, Mallory seems like a product on its way out. Out-of-stock x 3. If you have one, keep running it until it dies, but if not, another option might be a better starting point. The ZX distributors, or 280Z with a high-energy module (HEI or MSD), seem well-supported, and easy to wire. Not sure where 123 is business-wise, but they've been around with other car brands for many years so odds are they're safe.

If you post the part number of the Mallory unit you're planning to install people can offer more advice. I think that the fragility of the Unilite module was addressed by Mallory quite a while ago. It may not be an issue any more. Maybe that's what the "power filter" is for. Both Unilite and the Datsun-focused Pertronix parts are old technology that has been farmed out to cheap manufacturers and is barely supported anymore by anyone, from what I've seen. That's why parts are "out of stock". The name still holds sway, but the product is not "high-tech" anymore. I could be wrong but that's the impression I get. Low volume product just doesn't get the company support that the money-making stuff does. Not to harsh your mellow but something to think about. http://mallory-ignition.com/mmy/results/index/?top=%E2%A4%B7+Distributors+and+Components&top-val=%E2%A4%B7+Distributors+and+Components&year=1970&year-val=1970&make=NISSAN&make-val=NISSAN&model=240Z+L6+2.4+LITER&model-val=240Z+L6+2.4+LITER&engine=Engine&engine-val=&trans=Transmission&trans-val=&brand=Mallory&brand-val=Mallory&mmy-sku= https://prestoliteperformance.com/media/instructions/mallory/Mallory_Instructions_unilite_distributor_wiring_diagram_test_procedure_1214M_0000.pdf

"Unilite" refers to the triggering mechanism for spark. You shouldn't need any Pertronix parts. Pertronix uses magnets, Unilite uses LED light. It should install just like the 2363901, except that there will be no place to attach a vacuum advance hose.

Another one I came across. Who knows? But they don't have a physical address so still sketchy. I sent an e-mail asking for a quote. http://www.gearheadengines.com/products/showPart?year=1978&make=Nissan&model=280z&part_num=321&id_num=86612&selector=gasEngine

Here's an informative link - http://www.thezstore.com/page/TZS/CTGY/classic12c Seems like there's an opportunity here for somebody. If only I had taken a different path when younger...