Jump to content
HybridZ

Recommended Posts

3 hours ago, EF Ian said:

Thats a good weight for that setup, gives me hope.

His car is a series one, and yours is a non-US '78 260Z, so you should expect a bit more weight, all else equal. I read a post from John C once saying that an early 280Z chassis was 100lbs heavier than a late 240Z, and a late 280Z was 300lbs heavier than an early 240Z. Seems like a big difference for just a chassis (I believe that was the context) but that's the only info I've ever found. I have a '76 chassis and an early 71 chassis, and I'm hoping I can weigh the two while stripped down and compare. I don't know how the non US late models compare to the US models.

  • Thanks 1

Share this post


Link to post
Share on other sites

I will be getting her corner balanced after once the bare metal respray and rebuild are finished and its back on the road so we will find out, I'll post results here. Will have a carbon bonnet saving 10kg, fibreglass wings and alloy hubs saving another 10kg so I hope she is under 1200kg, 1150 would be nice.

 

It could be heavier than expected as you mention, might account for why mine is so stiff and I have none of the flex issues I've heard many early Z owners notice, my chassis is really stiff, jacked at the front with the doors open you can still open and close them normally, no visible flex.

Share this post


Link to post
Share on other sites
On 12/28/2018 at 2:48 PM, grannyknot said:

Give up the booze, potato chips and ice cream, that's another 10kg.:cheers:

 

On 12/29/2018 at 6:47 AM, EF Ian said:

Lol, might work for a lot of people,  but I already have <10% body fat.

 

Yeah... I've been working the opposite direction on that... Definitely building up that "dad gut". I could easily cut 20-30lbs off and still have a good bit to go. I definitely had more "excess" on my body than I've pulled off my car in sound deadener....

Share this post


Link to post
Share on other sites

Its hard to find time for exercise, but if you can you will definitely feel better because of it, both physically and mentally, with the added bonus of making your car quicker. I usually manage 5 days a week but the only time I can fit it during the week is a 8pm.

Share this post


Link to post
Share on other sites
21 hours ago, grannyknot said:

Less than 10%,  man that's impressive, you're already down to fighting weight.

I'm just lucky I was born with a body that just burns fat, that with an active job all day and at least 5 days a week training mean it tends to stay low despite me having to eat a lot due to the training.

Share this post


Link to post
Share on other sites
1 hour ago, evildky said:

Series 1 chassis, gutted and slutted, L28ET swap, 15x7 keizers, wieghed 2105 without driver at the DNI shootout before they changed the name to DNI shootout.

Whoa, that's impressive. Gives me a goal to shoot for. What was your fuel tank level at?

 

👏

Share this post


Link to post
Share on other sites

Having been around a series one and scrapped/used/sold a ton of parts between that and my early 280z I can tell you that the chassis on it's own is definitely noticeably different between the two, but isn't the biggest cause of the weight difference. 

 

Aside from just chassis reinforcements between years that add up to a fair bit, the R200 weighs WAY more than an R180. At least it feels that way when you're trying to lift them. All the EFI stuff is more weight, the bumpers are way heavier. The one most people seem to miss is the pistons themselves for the bumpers. Probably at least 10 pounds each corner. Bigger metal evap tank instead of smaller plastic one. A variety of emmissions stuff in the 280z engine bay is nonexistent in earlier models too. Rear struts are bigger/taller, which also means more metal for the strut towers on the inside.5 speed, if you have it is heavier. 240z didn't have a rear sway bar either. 

 

To be honest, other than the bumpers and emissions stuff, most of the things that make the 280 heavier are actually all good things for performance as far as I'm concerned. You can't have everything unfortunately. All else being equal, you can probably get the 280 within 200-300 pounds of the 240z, assuming the same equipment is on both. But then you have to deal with the fact that the 280 is a sturdier stronger body to begin with. I gave up the hunt for a 240z as a "superior" or more original car when I realized the only things I preferred on it were all basic styling cues like the lights and bumpers that tons of people have modified easily. 

Share this post


Link to post
Share on other sites

Just as a counter point, I had my 70 set up with L28/ZX 5 speed, R200, Autopower roll bar, Recaros, full carpet with a lot of extra sound deadening mat, and it was 2350, which is supposed to be the curb weight of the later 240s. 

I think there is a couple hundred pounds in the unibody alone. If you're looking to keep it stock, then you can make the case that the 280 is better because it is more rigid, but I think if you start reinforcing the chassis on either, you can get an equally stiff end result, and miles stiffer than the 240 or 280 chassis as they were delivered.

My early 240 now has LS V8, T56, gutted, I think it's a 12 point cage with lots of stiffeners including SFCs and strut tower bars, stitch welded, 15x14 steel rims, huge widebody, FG hood and hatch, Lexan side and rear windows, etc. Weight: 2352.

Look at something like Mike Kelly's car which was a 280 with similar amount of cage tubing, LS, T56, F8.8 rear, etc and I want to say his ended up at 2800+.

Edited by JMortensen

Share this post


Link to post
Share on other sites

I guess once you start adding all the extra tubing all bets are off, but mine won't really have any of that and will be almost entirely street. Then again, mine is a 75 which is the lightest of the 280s. I guess maybe I'm off on my guess, but 2800 seems ooo heavy for Mike's car. What year is his?

Share this post


Link to post
Share on other sites

IMO something else was going on with Mike's weight figures. There's other light 280z weights, even later years. I poured over Mike's build to find the weight when he first posted his results and the only conclusion I could come to without seeing the car myself is that not enough of the car was cut out in lieu of the cage and chassis stiffening installed. Mike also had a lot more work and weight put into aero than most which is definitely worth something that's often overlooked.

Share this post


Link to post
Share on other sites

Mike's car was a '76, and I believe it was something in the 2700lb range, not quite 2800+. Still really heavy.

 

I have both a '76 chassis, and an early '71 chassis. I'm hoping to be able to weigh them both as a bare chassis to get an idea of how much extra metal there is in the later chassis. But first I need to put some metal back into the '76 chassis. I'm also hoping to remove the 5mph bumper supports and see what difference that makes, I expect that's probably around 30lbs of metal there if I had to take a guess. My '76 chassis also has undercoating, so I'm debating stripping all of that off first, although I don't really want to, but for an accurate comparison it should probably be done.

Share this post


Link to post
Share on other sites
1 hour ago, Gollum said:

IMO something else was going on with Mike's weight figures. There's other light 280z weights, even later years. I poured over Mike's build to find the weight when he first posted his results and the only conclusion I could come to without seeing the car myself is that not enough of the car was cut out in lieu of the cage and chassis stiffening installed. Mike also had a lot more work and weight put into aero than most which is definitely worth something that's often overlooked.

Considering the fact that his cage didn't tie into the suspension at all, I suppose he needed all of the stock chassis for its stiffness. ;) 

As far as the aero, what did he have? A box from the dam to the radiator (which he said the guy at the wind tunnel poo pooed), vortex generators, and a spoiler. I think that was it. Maybe a splitter? I don't have VGs but I have a plywood splitter and big spoiler and sheet aluminum box to the rad.

Edited by JMortensen

Share this post


Link to post
Share on other sites

Looking back again there's less aero than my memory was serving me. He's running block plates along with radiator ducting with a tube frame radiator support. Not sure that's all that heavy. I thought it was running a full belly pan and more.

I need to get my car weighed soon...

Share this post


Link to post
Share on other sites

It's good to see this thread be reinvigorated... now running for over a decade!  And yet - has anyone, over these intervening years, actually weighed a bare S30 tub (with all bolt-on stuff removed, all glass and rubber and plastic removed, etc.)?  Has there been comparison between the 240Z tub and the various iterations of the 280Z?  This remains, I think, the burning question.

 

When this site first started, there was some flexibility in finding a 240Z as a starting-point, with the 280Z being an also-ran, a consolation or a shortcut, when the lighter and older vehicle couldn't be located.  Today, all S30s are rare.  None in any reasonable condition are offered inexpensively on Craigslist.  We have to modify and preserve whatever example we happen to have in our possession, even if it's the 77-78 heavier model.  Still, it would be  nice to know, what weight-penalty we're paying, in going form 1970 to 1978, in terms of things that are not bolt-on.

Share this post


Link to post
Share on other sites
23 hours ago, Michael said:

Has there been comparison between the 240Z tub and the various iterations of the 280Z?  This remains, I think, the burning question.

I have had two 240z striped down and on a rotisserie and they are certainly light, about 5 yrs ago when I was working on the first 240 I read on a thread here on Hybridz or ClassicZ  that a 240 bare shell weighed in at about 550lbs, I remember thinking at the time that the guy saying it was well know and reputable. Having spun my 240s on the rotisserie hundreds of times I would say 550 would be pretty close.  ATM I have a stripped 77/ 280z on the rotisserie and although it is noticeably heavier to spin I,m not sure where that weight is hiding. 

There is the extra weight of the bumper shock housings at the front, maybe 30lbs and probably 30-40lbs of bumper shock reinforcing at the rear. The floor pan rails extend back another 10-12", even being  generous that is 10lbs and there is the heat baffle between the spare tire well and where the muffler would hang.

I have to assume the rest of the 280 weight is in the doors, the R200 diff and all the extra bells and whistles in the engine bay.

Share this post


Link to post
Share on other sites

In addition to everything you listed, grannyknot, my impression has been that the 280 shells use thicker gauge steel in several areas than the earlier year shells.  I can even see the difference in sheet metal thickness in various areas between my early-model and late-model 260s.

Share this post


Link to post
Share on other sites

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 by rturbo 930
  • Thanks 1

Share this post


Link to post
Share on other sites

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).

Share this post


Link to post
Share on other sites

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.

Share this post


Link to post
Share on other sites

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.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×