WEIGHT REDUCTION?

[tickle]

HI EVERYBODY

could do with some pointers on whats road legal when it comes to weight reduction, the emphasis on my motor is to keep old skool looks, whilst trying to incorporate the lightest possible build i can but still keep the practical feel of the car inside.

so far i have removed:

glove box (cut down dash up to control panel)
sunroof mechanism (slide + tilt remains)
all sound deadening + carpet
central locking mechanisms
ski panel closing hatch
large bore drilled rear seat closing panel
airbox

i also plan to:

remove elec windows (swap for manual if poss)
remove elec mirrors
fit plastic or fibreglass boot, bonnet, f/wings + door skins (if legal)
build ally bonnet mounts and hinges
build ally boot mounts + hinges
replace glass with plexi glass (if legal)
replace boot floor with bonded c/fibre panel (if legal)
replace p/tank with ally minivan p/tank + fit in boot
fit caterham race seats
remove all extra bracketry from car
remove blower motor/ demisters


what do you guys think of these plans, and have you got any advise on what my options are. it's gotta be legal though, ive been hounded by police since i was a teenager so if i get pulled i will get fu**ed

[Taffy]

Why would you want to do this for a road car, really is not much point, sorry to be negative just can't see the benefit

[Matt_T]

Why would you want to do this for a road car, really is not much point, sorry to be negative just can't see the benefit

Maybe its a track orientated car but used on the roads too? I dont see whats wrong with it tbh, if it aint a daily driver and its only used for fun the why not?

[agent006]

Why would you want to do this for a road car, really is not much point, sorry to be negative just can't see the benefit

Because a trailer and tow car costs the thick end of £4k.

[tickle]

it nearing the end of it's life and so the sunroof is rotten anyway, so would benefit from removal (i am looking at fitting a plexi glass one, the headlining + sound deadening was manky, the carpet is crap ( both of them that i have )

i prefer a more basic set to the car and live right in the middle of lane central unused roads are a plenty! so it's everyday benefit to me as i am a keen driver and want to get into track days,

im also looking at fitting a r/cage + so weight reduction only seems to be a practical idea

lightweight panels are also rust proof + so are aluminium brackets so i can swap them on to my next car if this one dies too soon

if weight is not an important factor and is pointless why do racers concentrate on it at all, besides wouldn't you like to be able to drive a track spec car on the road too? hence the majority of modifications on cars these days.

[Lloydie38]

Hi,

I've been slowly stripping my E30 325i for track day use and the occasional drive on a Sunday morning over the TT course here on the Isle of Man.

The main use will be track days for me, as a daily driver from stripping it out you hear the smallest of stones against the underneath of the car and after a while with no ICE in the car it does get irritating (on the track theres far too much going on to worry about small details like that!).

As for legal road worthy stuff...Dunno I got my through the Manx test and that's a one off not like the annual MOT in the UK I've cracked on with the lightening process and upgrades which does make a real difference to the performance and responsiveness - See the car at http://whitetrack325i.webeden.co.uk/

Good luck with the project whichever way you decide to go.

Ian

[slowlysideways]

I'm currently at about 1022kg with minimal petrol...

See here for my latest antics: http://www.e30zone.co.uk/modules.php?na ... ic&t=35423


I want to get under a tonne, then i'll be happy(ish)

[tickle]

im sold on it now... good job as it's too late to go back

ive built a rear cage for the wee bi*tch (bloody hard work) and it's not bad even if i do say so myself, it's pretty light too.

didn't want to fit a full one as it seemed a little un-neccesary for what i wanted

my vision of the inside is starting to come together now wish it was finnished though.

i now have sorted

no rear seats (no room for fat people now)
rear cage
vibe st series speakers running through 2 channel vibe blackbox amp +mp3 player (no head unit) i need music to drive!
and all the previous listed items

im also g oing to replace the door cards with carbon sheet to help out with the feel of the car

realistically im probably only now slightly below standard weight without the grp panels but one day it'll all be mine

at least i can now enjoy the same responsiveness of an empty motor and know im safe if i hit a truck at high speed

[slowlysideways]

tickle - do you have any pics of your car? inside & out?

intruiged on the hole cutting in the rear seat back - as thats my next job

i've also got access to a pipe bender, so might be building me a cage too!

[Lloydie38]

Weight on mine is roughly 1042kgs with half a tank of juice - unless the scrap metal dealers weighbridge is out

[slowlysideways]

Lloydie - nice one, thought you were still at 1080kg?

Cool tho, keep it going son'

[tickle]

im tring to get hold of a digital camera and then ill post some pics

i drilled large holes in the raised areas of the panel, made sure not to drill on edges as it can lose alot of structure

what was the standard weight od a 318i anybody, just trying to figure out where i stand on total weight?

[Lloydie38]

Lloydie - nice one, thought you were still at 1080kg?

Cool tho, keep it going son'

Reduced sound deadening and for the sake of the track the spare seat came out too with the harnesses, front fog lights, plastic wheel arch housing, ski hatch, sunroof lining, BUT I'm going to get it weighed again at the DOT Ferry weigh bridge to make sure.

BTW I went for a blast in the 325 with the Manx Caterham club and I think they were suprised at how quick it was, as they were doing 115mph I was catching them doing 120+mph and then I changed into 5th just ran out of road. Not bad for a car totaling £4k compared to £20k+ on their caterhams

I might not be invited again

[slowlysideways]

tickle - any pics of the inside of yours yet mate?

looking forward to seeing rear bench

cheers

[tickle]

oop's forgot about that, ill get them up by fri

[Taffy]

"replace boot floor with bonded c/fibre panel (if legal)"

This is mainly what I was referring to, I know the cost of doing something like that and believe me it would be cheaper to buy a tow car, it was quite a sensible comment actually!

"if weight is not an important factor and is pointless why do racers concentrate on it at all, besides wouldn't you like to be able to drive a track spec car on the road too? hence the majority of modifications on cars these days"

I never said that, I said I couldn't see the point in going to that extent for a road car, for a racer YES. Anyone who knows what I do will testament to the fact that my race cars are if nothing else the best prepped and lightest cars on the grid, part of the reason why our E30 last season smashed 3 lap records and got 9 podiums, 6 being wins and outqualified E36 M3 and E30 M3's around Thruxton of all circuits.

If it floats your boat then fine, didn't mean to offend, just offering a view as to what is worthwhile and what is not, i have spent thousands on things that were not needed or didn't make a difference so felt qualified to make such a comment, it's very easy to waste money in this game

[tickle]

sheet of carbon fibre £90 ish
panel bond £50 ish

and a fair few hours of labour, im time served so won't have to pay someone to do it, i have a friend who works with composites(builds + repairs racing boats) so it isnt dear to me at all! in fact far cheaper than a tow car. why is there no point on a road car? is there no point in going fast in a road car?

if your thinking along those lines maybe elise's shouldn't have been produced, or maybe there was never any point in the mini lol.

don't see the problem myself and dont understand why ud want to put me off it. weight reduction aint just about how many seconds you save, the handling is the main thing to me. these german buses weigh loads

[Taffy]

Let's not get into a war of words here, I undestand the benefits of weight reduction on handling and improving handling results in lower lap times, they are inextricably linked.

You're forgetting that there is a huge amount of strength and rigidity and well (and i'm assuming you are referring to replacing the floor and removing the well and not adding a CF floor plate which would effectively add weight as it would be an addition) and removing it similar to removing the roof or a pillar, it'll make it all floppy and unless you can add that strength back in then it's doing more damage than good. We did something similar on the racer but we had a 42mm CDS tube running from turret to turret and down to the diff carrier and welded in a sheet of steel and it was fine. Iff you think you can replace that strength with a £90 sheet of CF and some bonding agent then good luck to you and I wish you well. Not trying to put you off, i'd love to see the results, go for it. But you did ask for advice on what was road legal and that is why I said it's not worth it, but hey it's your car and your money, just do it.

[tickle]

not tryin to get into war of words mate, soz. just keen to pull knowledge on this area.

would strength be maintained if a mould of the origional boot floor was done? that way all the stiffening presses in the origional panel might be maintained. or is it the structure of the material that is the problem.

this isn't something im gonna rush into. without a well mulled over design to follow, there is no point in tryin. i really don't expect this lot to be easy, if you racers use stuff like this its obviouslt top end stuff, thats why i want it sooo bad

[Taffy]

The thing is to keep the strength you'd need a cage or some form of strengthening, CF is 8 times stronger than steel for the same thickness but obviously hugely lighter, to get that strength back in using CF alone you'd need a moulded panel and that doesn't come cheap, but then it's only as strong as the way it's fixed, this is the other problem, bonding CF to steel just won't work and you'd need decent brackets and corresponding reinforcement in the CF to do the job properly. You see this is a specialist job and I doubt you'd have much change if any from 4k and that is why the cost would far outweigh the benefits, hence my original comment. Really didn't mean to sound negative but like I said it's easy to waste money on this sort of stuff, believe me I know!

Best way to lighten is just to be methodical and remove everything you can live without and leave it at that for a road car, if it's track only then remove everything and replace everything with lightweight panels and be meticulous and you'll get there

[tickle]

thats devestating news

didnt realise it was that tricky, so much for glues that are stronger welds, i always wondered why you werent alowwed to replace welds with that stuff for mot, just no-body ever gave me an answer.

sounds like this sort of stuff is only worthwhile if your going the whole hog and gettin a cf shell. and thats well out of my range! surprise

the problem with serving my time with ford was that if you asked a question you never really got an answer. as you can imagine this left some open loops in my knowledge. its a shame people in the trade don't seem to know as much as the people who are keen on this stuff, i knew i was wasting my time there!

thanks v.much for all your help geez