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1976 280Z Restoration Project

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Anyone know the correct length for the driveshaft to be cut between the second generation 5 spd and the r200 diff? I have a 280zx driveshaft with the correct splines, but I realize it may be too long and need to be shortened to fit my 280Z

Sent from Canadia

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I think that this might be backward. Don't forget that these are not "framed" cars. They are big sheet metal boxes, kind of like an old lunch pail. AKA monocoque or unibody. Best to use the welding to hold or create the shape, not bend the welding after it's done.

So I should strip the car to the shell, take it to be straightened, THEN do the floor and frame repairs? Don't I risk twisting it when I cut it all apart? Even doing one side at a time?

Sent from Canadia

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Not sure.  Many people have done what you're doing though.  Some say the box is fine without the floors, some say it's all wiggly and twisty.  There's probably a best method out there somewhere.  What I'm saying is that locking in a misalignment with new welded-in parts, then bending the box's new metal and welds to get the suspension aligned, could cause warps and bends in unwanted places.

 

My guess is that the best way to do it is in parallel.  At the same time.  Weld the parts in while controlling alignment.

 

Just bringing up a different perspective.  

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Is it possible to straighten it myself on the rotisserie then maybe? Like I said, I have all the measurements in the FSM...

 

When the floors are out, it should be fairly easy to pull and straighten with come-a-longs or a hydraulic ram.

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I have all the tools you are talking about but would never attempt to straighten my own car. The frame rack gives a great datum line to work off of and has zero flex. So when you pull or push against it the measurements are correct. The welds you put into the car to do floorboards or sheet metal repairs are harder than the original metal. It is probably best to get the car checked and straight then do one side at a time. Be sure to put the transmission crossmember in so the tunnel doesn't move on you. I commented on how I did my floor boards on another thread. When they were done they looked factory. At the moment I don't recall which thread and am too tired to figure it out... ;)

C

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The recommendation about the crossmember is good, but the later model Z's used rubber bushings on the member/body mounting points.  So it won't be rigid like an early 240Z would be.  False sense of security.  Still, you could tack in a brace or two, or drill a few holes to mount some strategic braces.

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I had noticed the bushings too. My plan was to weld in a brace temporarily. Not concerned about tacking a brace in as the whole bottom of the car is being refinished....

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See hazmat thread.

Read it, printed it, read it again...

What part are you referring too? He didn't do a complete floor pan removal.

Sent from Canadia

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Sorry, I am a bit of a dweeb when it comes to using a simple thing like a keyboard. I was referring to his back problems.

 

Mike

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New floor pans and supports arrived too! Starting to get excited for spring.

Sent from my iPizzle ringy dingy device....

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Cant wait to see some tear down pics! Have you looked under the battery tray, doglegs, frame rails, and spare tire well? These are usually hot spots for rust.

 

Anyone know the correct length for the driveshaft to be cut between the second generation 5 spd and the r200 diff? I have a 280zx driveshaft with the correct splines, but I realize it may be too long and need to be shortened to fit my 280Z


Sent from Canadia

I believe the stock 280Z shaft will work. I may be wrong though. 

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Cant wait to see some tear down pics! Have you looked under the battery tray, doglegs, frame rails, and spare tire well? These are usually hot spots for rust.

 

I believe the stock 280Z shaft will work. I may be wrong though. 

The rust looks minimal from above and the battery tray is pretty good. I know the car has been repainted several times so I am hoping that most of the rust has been treated/repaired at that time. I have not been under the car yet. I am a little scared to see the shape of things under there...!

 

There IS a ton of undercoating on the car though. The last guy COVERED the bottom of the car with the stuff and for good measure sprayed the whole engine bay and underhood with it too... FML

 

I have been trying to be patient. I really want to finish the garge before I start the tear down so I can do it properly. I want to have a clean space to start and proper shelving etc. I want to do a proper layout too (space is 24x24 dbl garge) and possibly include a paintbooth area that can be quickly setup and torn down. A friend of mine has hooked me up with a couiple industrial in-line ventilation systems and he will be building the downdraft ducting for it too. Go big or go home!

 

My next big question is: should I buy a dual media blaster kit that can blast soda as well as crushed glass etc or should I just mechanically strip everything on the body? The mess of media blasting the body (less sheet metal, possibly soda blasting those parts) is what's holding me back. Local companies start at about $1500 to blast a stripped body around here... I will be buying a proper sand blasting cabinet for the heavy duty stripping of old parts.

 

I will post a full journals worth of pics as I go. May even install a go-pro in the garage too!

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I believe the stock 280Z shaft will work. I may be wrong though. 

 

My info comes from here:

 

http://www.zcarz.us/TechnicalInformationPageTransmission.htm

 

DRIVESHAFT

 

(the tricky part in a 1st generation Z)

The Nissan T5 came with a special driveshaft to fit the 280ZX. It is stouter and fatter than other Z driveshafts, has a different spline count on the front end, and a square flange on the rear. In other words, the only driveshaft that will fit the T5 is the one that came with it. A 240/260/280 driveshaft cannot be modified to fit.

LENGTH: The T5 driveshaft is almost the same length as regular Zcar driveshaft, but the T5 transmission is a few inches longer. This means if you use a Nissan T5 trans/driveshaft in a first generation Z the driveshaft will be too long by about 2-3 inches. The solution is to have a custom driveshaft made, or have the stock one shortened. Most driveshaft shops can fabricate one if you tell them what you want, about $300. A cheaper solution for us budget ZCAR people is to have the stock one shortened and rewelded, about $100. This gets tricky because driveshafts should be shortened only at the ends for balance reasons. And for some reason Nissan T5 driveshafts neck down to smaller diameters right at the flanges. This means that after cutting, the yoke and flange ends are too small to weld up to the center tube.

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I don't have the Borg Warner 5 spd, but that might be my mistake in reading that article.... I have the "B" version (later) 5 spd. It is not clear as to whether or not my 280Z or 280ZX driveshaft will bolt up directly to the stock R200 rear end without modification.... ???

 

Can anyone clear this up for me?

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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.

Edited by Zed Head
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I have an '81 5 speed and my stock shaft bolted right up so you should be good.  :)

 

That is great news!

 

 

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.

 

 

So you are saying the 280Z shaft I have (stock) should bolt up fine to the 3.90 R200 (round flange) and the late 5 Spd transmission? If so, you have made my day... I was not looking forward to shortening a 280ZX driveshaft!

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I think the 280z drive shaft flange is square no? If so, you need to swap the companion flange from the 280z diff onto the 3.9 r200 diff. That's what I did for my car.

 

 

Also, if you are thinking about media blasting your car, you gotta be careful going too hard because it will heat and warp the sheet metal on your car.  My car had so much bondo and crap on it, they had to take the remaining material off by hand.

 

If I were to do my car again, I would get it acid dipped....

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So you are saying the 280Z shaft I have (stock) should bolt up fine to the 3.90 R200 (round flange) and the late 5 Spd transmission? If so, you have made my day... I was not looking forward to shortening a 280ZX driveshaft!

Sorry I missed this.  Yes, it should if the 3.9 came from a 280ZX NA engine.  The turbo cars with the "Borg Warner" transmission, used the 300ZX bolt pattern I believe, which won't work, but the NA pattern will.  The spline pattern and size of the slip yoke (the part that fits the trans.) is the same for all NA transmissions, way up in to the 1990 cars (71C transmissions)..

 

As I said, I have both a square and round flange differential in my garage.  One 1976, one 1978.  I've had them both in my car with the same driveshaft.

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