mark chandler
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| posted on 18/3/07 at 06:05 PM |
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Weighed my car today
Finished my build, just a bit of tidying left so popped down to homebase, 4 x bathroom scales @ £3.99 a hit.
So plonked it on the scales, front 80kg each side, rear 140kg & 60kg (uneven ground), so even allowing for error on the scales and not setting
the corner weights up I must be hovering at a max of 400kg.
Must go and find a flat floor now and set it up properly.
Feeling pretty pleased with myself now, kept throwing things away if they felt heavy.
Regards Mark
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DIY Si
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| posted on 18/3/07 at 06:12 PM |
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That sounds very light! Most Indy BEC's I've seen weights for are around 500kg, give or take a bit. Have you gone to any lengths to keep
it lightweight?
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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BenB
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| posted on 18/3/07 at 06:36 PM |
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Mine weighed 540kg @ SVA with a 90kg me in it!!!!
Aluminium floor but that's about it for saving weight.... I suppose I only had one seat too....
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Hellfire
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| posted on 18/3/07 at 07:25 PM |
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Hi Mark - I would be very doubtful the figures those scales are reading are anywhere near correct.
Most scales are widely inaccurate at weights upto 22 Stone 
I'd reserve commenting on such a light weight until you get it on a calibrated weighbridge.
Just my advice...
Steve
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ChrisGamlin
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| posted on 18/3/07 at 07:45 PM |
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What do the scales go up to maximum?
Agreed on the innacuracies, Ive had mine properly weighed as mentioned in the other recent weight thread, but Ive also got 4 bathroom scales for setup
purposes and although they are fairly repeatable results so can be used to tweak corner weights, the figures themselves aren't accurate
[Edited on 18/3/07 by ChrisGamlin]
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Gav
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| posted on 18/3/07 at 09:05 PM |
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I dont think that marks car is an MK indy, but a self built tube chassis with independant suspension.
Edit: Sorry Si thought you said MK Indy...
[Edited on 18/3/07 by Gav]
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Hellfire
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| posted on 18/3/07 at 09:22 PM |
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Gav,
According to his Building statement it's a BEC Indy using tube.
Wouldn't want to be incorrect....
Steve
[Edited on 18-3-07 by Hellfire]
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Danozeman
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| posted on 18/3/07 at 09:44 PM |
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That would be a nice weight but i wouldnt go by that. Take it down your local scrappies and have it weighed.,
Dan
Built the purple peril!! Let the modifications begin!!
http://www.eastangliankitcars.co.uk
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ChrisGamlin
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| posted on 18/3/07 at 10:00 PM |
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They aren't going to be particularly accurate though, I think the only way to be sure within a few kgs is to get it on a decent set of
cornerweight scales.
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Gav
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| posted on 18/3/07 at 10:36 PM |
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Apologies  
quote:
Originally posted by Hellfire
Gav,
According to his Building statement it's a BEC Indy using tube.
Wouldn't want to be incorrect....
Steve
[Edited on 18-3-07 by Hellfire]
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DIY Si
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| posted on 18/3/07 at 11:10 PM |
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Was going to say, I could've sworn I did say Indy BEC's!
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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Johnmor
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| posted on 18/3/07 at 11:31 PM |
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Scales
If your going to weigh the car like that remeber to put a block of equal height to the scales on the other side of the axle being weighed or all you
are doing is weighing againt the compression of the coil spring as suspension makes up the difference in height.
The ground has also got to be level.
I did mine and it came within 5kgs of the weight at the SVA test.
I want to shave around 50kgs of the weight of the car over the next few weeks.
Its weight too fat,
760kgs
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mark chandler
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| posted on 18/3/07 at 11:39 PM |
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Yup I agree, scales for £3.99 will not be that accurate, but when loaded they all read pretty much the same and I could swap them around the wheels
and get the same results. Okay maybe they read light to suit silly people but I got then to balance the cars corner weights.
I purchased 4 scales so the numbers are the total weight of the car shared across all 4, the plan is to find level ground, set the scales up using a
bit of clear pipe with water to get them at exactly the same height, calibrate scales at 100kg (4 x 25litre drums of water) the start in earnest.
The car is extremely basic, although not a power lifter prior to fitting the wheels I could struggle to pick up each end, fitting the wheels tipped
the balance on doing that.
I could not dead lift 200kg, maybe when I was 20 but that is now just a distant memory.
Round tube chassis, ali floor, and 893 blade engine which is not that heavy.
light brakes & hubs Fibre glass wings, nose cone and seats, all other panels are ali.
The acid test is how fast it goes, the weight is immaterial but its nice to speculate.
Regards Mark
[Edited on 18/3/07 by mark chandler]
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ChrisGamlin
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| posted on 19/3/07 at 01:11 PM |
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Hi Mark
Your spec is not dissimilar to mine although mine has a live axle (which is a few kgs lighter overall than an IRS setup with Sierra diff) but a steel
floor (~7-8kgs disadvantage) and that came out at 435kgs on accurate scales, so Id be quite suprised if yours was near 400kgs, let alone under it.
I can also just about lift the rear end without wheels on, but you're not deadlifting 200kgs when doing that because all the weight is not
centred around the point you are lifting from. Effectively the length of the chassis is a nice long lever with the weight spread along it, so you have
mechanical advantage in your favour if lifting from one end, and the actual weight you are lifting will depend on where along that lever each heavy
component sits (ie things near the pivot like engine etc will not act as much as things like the diff which are near the lifting point)
Also, say you're lifting the rear end, firstly you've taken off ~25kgs by removing the rear wheels, then because the front wheels are your
pivot point you're not lifting those (unsprung) parts at all, i.e the front wheels / tyres / hubs / brakes / uprights etc all stay on the
ground, so thats another ~40kgs, and then any weight forward of the centreline of the front wheels will be acting as a counterweight so actually
helping you lift 
[Edited on 19/3/07 by ChrisGamlin]
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mark chandler
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| posted on 19/3/07 at 08:02 PM |
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As I said above, " its nice to speculate".
Yes I know picking up the back is not the same as dead lifting, every mm forward the car is acting as a lever, but that aside my engine is 5 kg
lighter than an r1, I do not have an engine cradle as this is incorporated in the frame and its round tube so lighter by default its getting closer,
although not dissimilar to yours.
Regards Mark
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ChrisGamlin
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| posted on 19/3/07 at 09:34 PM |
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Yep nice to speculate, thats all we're doing too though
The weight above was a few years ago when I still had the blade installed though, but having had both engines side by side in the garage I don't
think a blade is any lighter than an R1, if anything Id say its the other way round judging from the highly accurate "how easy is it to pick it
up" method
cheers
Chris
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