weight shaving

MrB

MrB

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ESSEX UK
im in the process of trying to get as much weight out of the car as i can, if i list a few bits ive done let me know if there is anything else i can do please . whilst the weld in cage is being sorted and the windows etc are ut the car i want to get as much out as i can

remember this is also a road car

complete aircon removed
powersteering pump removed replaced with smaller electric pump
water pump removed replaced with electric pump
brake servo removed replaced with ap racing race pedal box
HIcas removed inc ECU and wiring removed
Rear seats removed
front seats swapped for bucket seats
roof lining removed
interior lighting and wiring removed
door cards removed
rear panels and side top panels removed
carpts removed
sound deadening removed
spare wheel and jack removed
stereo removed inc wiring
speakers removed inc wireing
dash dials removed replaced with mtx dash and small indicator markers etc wiring removed and replaced with new smaller loom

Perspex side and rear windows on order

is there anything else to do can i tank cut inner metal panels as the strengh will be in the cage or is that going too far

thanks

brett
 
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Talon (the guys who built my toy although admittedly its not a drag car :) ) removed the side impact bars inside the doors as my roll cage has door bars, I've also seen cars with the spare wheel well cut out & replaced with an ally sheet. Have you considered Carbon/fiberglass panels too?

Loz
 
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door bars is a good idea, hadnt thought of that. soare wheel well is coming out so the swirl pot etc has a good base to stand on.

panel wise were looking at carbon, carbon bonnet carbon boot carbon wings and carbon door skins
 
have you thought about aving the passenger seat secured with wingnuts to remove it quickly once you get to the strip. basically remove the bolt and replace with a lengh of studding, tack the studding in place so it doesnt come out easily and wing nits with spring washers on top.
2 mins to remove the seat.
 
How heavy are your wheels and tyres? It surprising how much weight difference there can be with the wrong wheel selection. As this is essentially unsprung weight it is good to minimise it.

I hear a lot of people cutting out the inner arches etc but personally I think this is going a bit far. How heavy is the green paint?

Other ideas maybe a lighter Fuel tank? Steering wheel. Drill the pedals etc. Nip off the ends of all nuts. Save 1g from 100 places and it all adds up.
 
pgarner said:
have you thought about aving the passenger seat secured with wingnuts to remove it quickly once you get to the strip. basically remove the bolt and replace with a lengh of studding, tack the studding in place so it doesnt come out easily and wing nits with spring washers on top.
2 mins to remove the seat.
Click to expand...

Another V good idea
 
fuel tanks an issue but cause its a road car as well and the standard tank only holds 60ltrs anyway that aint going to get me too far as it is plus the standard skyline tanks aint that heavy.

im thinking of changing the rear sub frame for an S15 item as its pretty much the same but the s15 doesnt have hicas so it doesnt have anoy of the mounting points which is a small saving

ive sorted the windows ive gone for polycarbonate so its approx 50% lighter than the standard glass. the wireing loom has been stripped out and a new one is being made without anything unecesary in it ie the hicas loom is an inch thick thats gone all the roof lighting wires have gone all the dash wiring has gone as the dash works off a com port on the ecu so it has very minimal wires for warning lights on indicators etc
 
Would it be viable to remove the heater matrix & the associated plumbing & install an electric one sufficient to stop the car steaming up? This is addictive I can't stop trying to think of ways to lose more weight! :amuse::lol:
 
Not saying that you need it, but the easyest way to save weight and cost as little as you want it to loose a bit of weight off your self lol.

(not saying that your a fatty lol, but if you could afford to loose a few pounds that could help out without costing anything really )
 
I think OG would be the best to ask about this, he is making an EXTREME elan as light as he can get it with as much power as it can take.


lightweight bolts and nuts in lowstress areas?

lightweight intercooler?

umm,,, cant really think of that much as you probably have already thought of them.

as waynne said, 1g in 100 places will all add up.
 
screen wash bottle has been removed and relocated to the back, it is smaller but will help keep a little weight still over the back wheels.

as for me losing weight ive just installed a 3k gym at my house so working on a bit of toning on myself need to lose a little bit of a beer belly

LOZ
i like what you say here ive already removed all the air con parts of the system under the dash and removing the rest of the heating system for a lighter electric version does sound cool could be plumbed behind the dash to stll flow through the normal vents without the weight of the whole system. + less water lines coming into the car a little bit more of a weight saving. anyone now of a system and were i could get it plus possible cost i like this idea

ive found there are loads of little panels and brackets spot welded n the car in the boot, under the dash and on the interior etc there dont seem no need for them and some it seems hard to know what there purpose was anyway so spot weld drill coming out to get rid of all of those
 
I'm back! :bigsmile:
Remove the height adjustment motor units from the headlights, I've done this on another car because I didn't want to fork out for a whole new headlight assembly (Smart city coupe, £200ish). The tricky bit is setting the light to the correct height, but it is do-able.
 
the tripple plate clutch is quite weighty but ive had the flywheel lightened when its was rotation balanced along with the crank etc.

propshaft wise i tried to get a carbon one but the company that make them ( torqueline) wont do it due to the lengh of the prop they said a carbon version will only take 600bhp which aint half as good as it needs to be. i told the guy i wasnt bothered id just buy another if it broke and he said no he doesnt want eople thinking his product is inferor, which is fair enough. ive sent specs to a couple of companies and im waiting to see if i can get one knocked up in allie.


its fantastic to get this feedback and ideas guys i posted this on the skyline site as well and got nothing back at all but then half of them think im crazy for doing this work to a gtst lol
 
Loz said:
I'm back! :bigsmile:
Remove the height adjustment motor units from the headlights, I've done this on another car because I didn't want to fork out for a whole new headlight assembly (Smart city coupe, £200ish). The tricky bit is setting the light to the correct height, but it is do-able.
Click to expand...

looked at this today and ive come up with another option on this one taking your idea a little step further, the car has dual square lights in each headlamp, what im thinking of doing is removing the driving lamp and replacing it with a hella 50mm projector light, there is the option to swap the main beam for 90mm projectors as well, but before going that far i will see how hard the mounting plates are to make for the other pair. ive found a guy in aus whos done the conversion already so im waiting for areturn email with some instructions hes promised me. i have priced the lamos and to convert all 4 swaures to lightweight round lamps £450.00 which aint too sad. i'll post a pic up of the skyline ive found with this conversion so u can see and tell me what u think

sorry for the slow replies guys im sending this link to work so i can get intothe site there so expect better replies as of tomorow
 
untitled3.jpg

untitled2.jpg


these pics will give a good idea on the lights this has had just the 50mm and 90mm conversion which i think looks pretty cool. use plastic or carbon to mount them should make a little saving
 
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Right.... A few questions first:

What use will this monster be put to? Drag, sprints, TOTB, Limited or frequent road use?
Daytime use only or night use as well?
Proposed power?
Planned vehicle weight?
One driver or many?
 
What use will this monster be put to? Drag, sprints, TOTB, Limited or frequent road use?
Daytime use only or night use as well?
Proposed power?
Planned vehicle weight?
One driver or many?
Click to expand...

Drag definete, possible totb. limited road use mostly at night

proposed power 850ath

planned vehicle weight as light as i can get it

just the one driver
 
had another idea today not sure if its totaly possible what do you reckon.

the rear brakes have discs and bells so i have callipers and shoes inside working on the drum well

because ive removed all the standard brake lines and im replacing them with braided lines and aeroquips im thinking remove the complete handbrake assembly and fit a lighter latching hydraulic handbrake that works the rear calipers instead of the drums then remove all the innerd like shoes and springs etc from the rear drum including the handbrake cable. should be possible shouldnt it ??
 
MrB said:
Drag definete, possible totb. limited road use mostly at night

proposed power 850ath

planned vehicle weight as light as i can get it

just the one driver
Click to expand...

In no particular order:

TOTB means car needs to handle. Reduce unsprung weight, as 1kg of unsprung is worth around 6-8kg sprung weight in the handling stakes.

Do you really need such large calipers?

3-piece alloy billet wheels are usually lighter then 1-piece items. This helps by reducing the mass the engine is trying to turn.

With regard to 'as light as I can get it' - wrong answer :) You need to have a target, otherwise you don't know how well you are doing. For example, I am aiming for a maximum weight of 600kg, but looking for 550kg.

By keeping a log of weight savings I can see how well I am doing. If, once car is built, it is heavier than expected, I know that I still have some work to do. If you have no target, the car will end up heavier than it could be.

Use aluminium nuts, washers and bolts where strength is not an issue. Where it is, use the proper nuts and bolts (and new ones) but keep length to a minimum, making sure that at least 1 1/2 threads protrude out of the nut. If possible, use half nuts. Don't use a washer unless actuallly required. Colin Chapman (founder of Lotus Cars) used to say, 'don't take a washer for a free ride'.

Think about brackets. Can they be used to hold more than one item? Can they be made lighter by drilling holes or using narrower or thinner material?

Alternator - Is there a lighter alternative?
Starter - ditto

Propshaft. Carbon is good for drag racing as it absorbs some of the shock loading experienced off the line. Not cheap, I was quoted £2000 for one for the Elan (approx 600mm long) so I am going to go the alloy route.

Seats. As you will be the only driver, no need for an adjustable one. Remove original seat frames and replace with lightweight non-adjustable versions.

Do windows need to open? If not, then polycarbonate can be thinner than original glass, saving a few more grams :)

Carbon fibre cam cover.

Consider heated front screen rather than demisting heater.

Check out whether single wiper blade conversion is lighter than existing twin blade system (unless car is already fitted with one).

Roll cage can be made from lightweight (but expensive) materials.

Route all wiring/pipes etc along passenger side (where possible) so as to help in weight distribution.

Keep coolant pipes as short as possible so as to reduce vulume of coolant required.

Wire - Use the lightest weight possible for the current requirement and keep runs as short as possible.

Battery - As small as possible, taking into account expected load. Mount as close as possible to starter in order to keep heavy cable length as short as possible. Also mount as low as possible in order order to lower CofG. In fact, mount everything as low as possible.

How much paint is there on the car? Paint is heavy :)

If asthetics aren't an issue, only have one door mirror.

Exhaust. use the correct size pipes, rather than the 'bigger is better' Corsa/Saxo philosophy. This can save a fair amount of weight. Consider exiting exhaust out of side rather than rear in order to reduce amount of heavy pipe required.

I have no idea of the structural design of the body, so make no suggestions on where this can be lightened.

Hope this is of some use.
 
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wow some great points. gtting my pad out now and listing some stuff down, i have been keeping a record of the bits ive taken out as ive been doing it, but i hadent thought about an exact weight i was trying to hit..
 
MrB said:
thinking remove the complete handbrake assembly and fit a lighter latching hydraulic handbrake ?
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Hydraulic handrakes are not legal on cars made after January 1968. If noticed by MOT examiner it is a fail.
 
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does that count even if the handbrake has a latching mechanism ?? i know a lot of the hydraulic kits dont but there are a couple that do have them fitted.

thats possibly killed that idea then lol
 
MrB said:
does that count even if the handbrake has a latching mechanism ?? i know a lot of the hydraulic kits dont but there are a couple that do have them fitted.

thats possibly killed that idea then lol
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Yup, it has to be mechanical. Hydraulic would probably be heavier anyway, what with the pipes, master cylinder, reservoir and fluid. Just lighten the existing one.
 
Cool cheers for that.

expect a few pm's steve as i come up with stripping ideas lol

gonna be intresting to get this on a set of scales with a standard gtst once its done and see what the weight difference will be
 
steve. another brain picker cause your def the man that knows

im going to be looking at the car this weekend and making some decisions from your advise ie what i want to achiece in a weight aspect etc

BUT what about

weight distribution. what is best, obviously weight low down in a car is good for a center of gravity aspect but whats best for say battery, oil can, catch tanks extinguishers etc . is it best to go as central as possible of if say a oil tank is up front counter with the battery at the rear ??
 
I've always thought a 50/50 weight distribution is ideal. Alfa put the gearbox over the rear axle to achieve this.
 
MrB said:
weight distribution. what is best, obviously weight low down in a car is good for a center of gravity aspect but whats best for say battery, oil can, catch tanks extinguishers etc . is it best to go as central as possible of if say a oil tank is up front counter with the battery at the rear ??
Click to expand...

A car with a 50/50 weight distribution will tend to understeer on corner entry. A better ratio would be 45/55 or even 40/60. This allows the front tyres a better chance of turning the car into the corner as the weight trying to push them in a straight line is less. More weight at the back promotes oversteer (or reduces existing understeer), so helping quick cornering.

On the drag strip, more weight over the rear wheels equates to more grip. Less weight at front encourages rotation about the rear axle thereby transferring more weight to the rear.

For the track, the lower the centre of gravity, the better. On the strip, the reverse is true.

On the track, keep as much weight as possible between the axles and as near to the centre of the car as possible. This includes the driver (the heaviest movable item in the car) so move the seat as near to the centre as possible, Even the odd inch will help.

On the strip, keeping weight near to the centre is not so important, but weight distribution between rear wheels is.

If car is to be used both on the track and strip, compromises have to be reached based on your preferred sport.

What bits you put where is up to you. For example, the battery can be heavy and useful for altering weight distribution, but placing it in the rear will result in a lot of heavy cable!
 
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