Z Car weights

[rturbo 930]

I can tell you that the reinforcement in the doors adds 10lbs per door. I'm not sure that the bumper reinforcement stuff weights quite that much, based on a rough estimate of the square inches of metal, and the weight per square inch based on the thickness of the metal. I'd guess more like 15-20lbs per end. Could be wrong.

 

Other areas of the chassis where early 280Zs have extra weight are the front frame rails, which, IIRC, have a reinforcement on the inside, the lower rad support, the rear strut towers, subframes under the floor, lower rear quarters, various bracketry, and likely a handful of places where you can't see that something's been added. Later 280Zs have even more reinforcement, notably in the door jamb area, and the spare tire well/gas tank area. John C has a few posts on the differences, and I believe he mentioned some additional metal in the roof structure as well, although I'm not sure if that was all 280Zs or just later ones.

 

The series one shells do use thinner metal, I checked a few areas with a micrometer, and compared between my early '71 and '76 280z, as well as a few pieces from a '72 240z. the early '71 sheet metal came in around 0.9mm, whereas the later sheet metal came in slightly thicker at about 1mm.

 

I believe (I'd have to look it up to be sure) that John C has also said that the early 240Zs and later 280Zs are 300lbs difference, and the late 240Zs and early 280Zs are 100lbs difference.

Edited January 28, 2019 by rturbo 930

[Michael]

I have two data points, for both of which the evidence is scant and only qualitative: a 1972 240Z, and a 1978 280Z. I partially gutted the doors of my 280Z, removing the longitudinal crossmember and a good portion of the inner-wall sheet metal.  I placed the detritus from both doors in a cardboard box, and weighed the box.  It was, if memory serves, 10-12 pounds.  The 240Z door shell-material may be lighter gauge, but the architectural difference between the two sets of doors is worth only 5-6 pounds per door... if that.

 

My original 240 ended up getting sawz-alled (is that a verb?).  I was shocked by the thinness of the sheet metal... but wasn't sufficiently engaged to measure it with calipers.  Before cutting the tub apart, I used vice-grips to pry apart, peal back and cut chunks of sheet metal.  Later, I did the same for the front bumper supports on my 280.  The qualitative difference in sheet metal gauge was... significant. 

 

My casual hypothesis is that the preponderance of the weight difference in going from 1970 to 1978 is in the gauge of the sheet-metal, rather than the engineering of the tub (bumper supports, radiator supports, A-pillars, subframe "connectors", etc.).

 

To Grannyknot's point...since your 280 tub is on the rotisserie, would it be possible to weigh it?  Bathroom scales are notoriously inaccurate, but at least it's something... they have typically a 300 lb limit.  Perhaps one scale could be put at each end of the rotisserie?  Or would that damage the scales?

 

My stripped 1978 280Z - with a fairly elaborate roll cage, a 454 big block Chevy and a Doug Nash 5-speed, weighed 2720 lbs, on 4 Longacre scales.  This was with, at the time, cast-iron heads, most stock sheet-metal intact, stock hood etc.  Since then, I've replace heads/water pump/etc. with aluminum, and have removed quite a bit of metal, undercoating and other bits.  Hood is now fiberglass (homebrew design).

[seattlejester]

@Ben280 Had some interesting number when I spoke with him. Something along the line of the doors being much much heavier than I expected. Like 70-80 lbs for the 280z?

[ZHoob2004]

70lbs for the 280z doors (especially the late years) wouldn't surprise me. Both my doors are bare right now but I'll try to remember to weigh them when they get back together. The car is also currently a bare tub (with rear suspension and diff) so it wouldn't be much work to get a weight for an almost stock 77 shell.

[JMortensen]

Couple anecdotal points from years gone by:

1. 280 doors are much heavier. My BIL bought a Z junkyard and I helped him move all the stuff. I can't remember the number of doors that he got in the deal, but was upwards of 50. You can REALLY feel the difference after you carry about 20 of them from one side of the yard to a moving truck and lift it into a rack. Pick one up: "Oh shit, another 280 door!"
2. I stripped a '71 in the early 90s which I would now consider to be "'nearly rust free" and at the time I thought was "too far gone." My friend and I lifted the shell, just the 2 of us. Couldn't have weighed much more than 250 or 300 lbs, I'm guessing.

[Gollum]

I'm starting to be curious how light 240z doors are. My gutted '75 doors seem very light to me. Majority of the door weight is in glass and window mechansims (which I ditched).

[JMortensen]

This thread says 52 lbs for 240 door, loaded, and 68 for a 260. I saw 66 quoted for a 78 280 door in another thread, so they're probably pretty close and it's just the bathroom scales that are different, I'm guessing.

[grannyknot]

19 hours ago, Michael said:

To Grannyknot's point...since your 280 tub is on the rotisserie, would it be possible to weigh it?  Bathroom scales are notoriously inaccurate, but at least it's something... they have typically a 300 lb limit.  Perhaps one scale could be put at each end of the rotisserie?  Or would that damage the scales?

I don't think bathroom scales are up to the task but if I can find somewhere that will loan or rent me a hanging crane scale I could lift each end one at a time with the engine hoist and calculate that way.

[calZ]

Four bathroom scales would do it

[NC88]

You can always use a lever arm (ruggles scale method) if your scale(s) is  rated less than the item you are weighing.

[grannyknot]

Ooooow, look what I just picked up on ebay,  I won't get it for a couple of weeks but will post numbers when I get it.

 

[Zetsaz]

Very Cool! My interior on my 75 is stripped down to nothing currently, other parts only include a bare block/transmission and full suspension. I really should have weighed the shell when it first arrived from the previous owner, but there's a chance I can take an afternoon to prop it on blocks and temporarily disconnect everything.

 

 

[Ben280]

I weighed my 280 shell before and after I had the cage put in so I could keep an eye on what it all weighed. As a roller, no glass, no interior, but suspension/diff etc all in, the car weighed 1173# (see photo for car as weighed). Post cage that weight went up to 1293#, and as it sits now, in full fighting weight it's 2180.

[grannyknot]

Ok, just took the 77/280 off the rotisserie so had a chance to weigh it, this is just the shell, all paint was removed then 2 coats of epoxy primer were applied and 2 coats of undercoat, the only thing left on the car is the vinyl headliner and the 2 rear wheel arch vinyls. 

Now I'm not 100% on this method but I couldn't think of any other way to do it with what I had on hand.  With the car level the rear measurement  was taken with the car hanging from the rotisserie bar that bolts on where the tie down hooks usually are, then jacks were placed under the rear rotisserie bar and the front was weighed hanging from the front rotisserie bar that is bolted to where the bumper shocks attach just in front of the radiator support.

I checked the accuracy of the crane scale by lifting my small anvil which I know is 118 lbs and it was bang on, 

I have to apologize, I forgot to take a pic of the rear measurement but it weighed 289 lb, front was 246 lbs

289lbs

246lbs

535lbs minus the 6lbs of the rotisserie bars, is 529 lbs

Someone with better geometry skills than me will have to verify if the method I used is valid.

 

Edited March 1, 2019 by grannyknot

[Jeff]

6 minutes ago, grannyknot said:

Ok, just took the 280 off the rotisserie so had a chance to weigh it.......

 

535lbs minus the 6lbs of the rotisserie bars, is 529 lbs

 

 

I would say that is right on the mark.  I'm the guy that weighed his bare body shell, early 260Z, on 4 bathroom scales and my result was 520 lbs.  I found the old files on a hosting site I haven't paid for in years but unbelievably they're still there.  Fifth picture down shows it being weighed.  My 260Z beign weighed  

[rturbo 930]

I would expect much more than 9lbs difference between a late 280 and an early 260. 529lbs isn't a bad number though. If I'd had to guess, I think I would've put it closer to 600lbs.

[grannyknot]

38 minutes ago, rturbo 930 said:

I would expect much more than 9lbs difference between a late 280 and an early 260. 529lbs isn't a bad number though. If I'd had to guess, I think I would've put it closer to 600lbs.

Same here, I was quite surprised.