budd

iTrader: (5)

I've pottering around with it today and started is weight lose program, first item removed was the space saver spare /jack etc weight saving 18kg (the spare weighed 16kg on its own!!) next to go was the A/C pump saving 8kg, next the rear speakers another 4kg total so far 30kg, lots more must to go!!!

I'd like to lose around 100kg,so another 70kg to go, I don't whether this feasible or not but I do need to shed weight!!! or once the cage, fire system etc is fitted it will end up weighing more than stock and that will never do .
So what shall I remove next and what will give the biggest weight reduction is one go, so far the spare wheel as contributed 16kg to the program which is pretty good for one item??? so what next suggestions welcome,

dunx

iTrader: (3)

What do the regs say you can remove ?

dunx

sco8bystu

cant you just strip the lot and leave what you need to run it and your clocks? if regs say bits need to be there then just put the bits needed back in place? i would go for some lighter seats as the ones you got in there weigh an absolute ton

steve jackson

iTrader: (2)

Chisel all the black sound proofing from the floor pan.

Have a look here may be of use : 22B Bulletin Board: rollcage fitment/weight loss

Steve

hostagekilla

What about a fibreglass bonnet and boot lid, and front wings maybe?? They might be flimsy, but if your only using it as a track slag it'll save you some weight innit

budd

iTrader: (5)

All good suggestions and your quite right I need to check the regs, there are 2 classes production or modified, in modified you can pretty much do what you want so long as it retains the basic shape of the car so carbon /GRP body panels ie bonnet , wings etc are all OK and all the interior can be removed, but I'm aiming at the production class to keep costs down, and this seems to cause much controversy and discussion, it’s all about ‘the spirit of the rules’ which are pretty ambiguous and open to interpretation apparently the interior can’t be totally stripped and must retain some of the original trim but how do you judge what’s allowed or not ? same with the body I know I can’t use non std panels but can I chop away metal from the structure eg removing the boot floor? I’ll ask the questions on the Nippon challenge / Subaru Cup forums before committing to much butchery. But stuff like the sound deadening saves loads of weight( I took 3 carrier bags of the bitumen stuff out of a Nissan 200) it’s the next job on the list, plus it’s a good time of year to remove it, while it’s cold and brittle in the it chips off easier.
The seats are a given and required for the series a cheap FAI race seat weighs in at about 8kg I’ll remove a std seat, weigh it and see how much I could expect to save here. Other things are air bags plus associated wiring (easy to locate and remove due to it being wrapped in yellow tape), plus removing little brackets etc and then drilling holes in everything.
So tomorrow I’ll be chipping away at sound deadening plus I’ll have a look at the doors see how much I can chop out while retaining function.

budd

iTrader: (5)

interesting thread, and it's the same OMP cage as I plan to use.

dunx

iTrader: (3)

My seats are 20 kg's each....

Ally bonnet from an STI is an expensive, but std part.

Good luck !

dunx

sco8bystu

do the seats have to be standard to meet regulations? if not i have a pair of cobra classics sat at the bodyshop

corradoboy

Front seats are usually 20-25kg each, so a single 8kg drivers seat is quite a saving. The back seats coming out are a given, and quick and simple to do. Seatbelt mechanisms and their mountings are very heavy, hence harnesses give a big benefit. The battery can be replaced with a bike one, and relocated to the boot to aid weight distribution. Windows can be replaced with acrylic/perspex and the winding motors and mechanisms removed. Rear screen can be replaced too. Most spoilers do sweet FA for aerodynamics, so may as well be ditched, along with any other cosmetic body parts (plastic sills, spats etc).

budd

iTrader: (5)

I don't think I'm allowed to use STi parts (but I'll double check) the plan is to light the original bonnet by cutting all the support ribs out, hopefully this should do the trip and no cost

Seats ( well drivers ) needs to be FIA homologated to comply with series regs.

I've cleared all the sound deadening out of the boot today and started making a mount for the battery ( but I can't find the roll of battery cable I have, I'm hoping it's up at my other garage if not it could have being in the back of a Volvo T-5 I've just weighed in DOH!!)
So the battery will have to wait until I find /get somemore cable, I'll probably use a Varley Red Top battery for races and swap back to a normal one for road use, but a bike battery may be a cheaper option, it's deffo worth looking into.

I don't think I can use plexi windows in production class, and I think you may be right about spoilers they do generate drag and are only really effective at high speed, I guess only a back to back test will show up differences in preformance / stability.

tweaks

iTrader: (7)

what about rear wiper and motor (i'm guessing its a uk ???) roof lining,pillar trims ect...

Tim

sco8bystu

only difference between both bonnets is ones alloy they look exactily the same but the alloy one weighs loads less...like instead of having arms like arny to open it peewee could do it..

tweaks

iTrader: (7)

alloy bottom arms ???

Tim

corradoboy

Lightweight alloys make a massive difference. Even my missuse could tell the handling and responsiveness differences when I swapped to OZ Superlegerra's. Check the weight of your current wheels and compare it to the 5-8kg (? size) of the OZ Ultralegerra.

budd

iTrader: (5)

I don't think I'm allowed to run STi parts, Sti's aren't allowed in the production class to keep costs down

The car is fitted with 7x17 Kei Racing 'Flux' alloys, I'll strip a trye off and check the weight, but to be honest I'll probably keep these till they get damaged or a set of lighter ones come up cheap, I need to spend money on the brakes (it's fitted with UK spec single pots ) at the very least I need Subaru 4 pots.

corradoboy

On a UK Classic pre'98, the brakes should be amongst the first things modified !

A quick Google shows the Kei Racing wheels to be as light as the OZ's, so no need to change.

budd

iTrader: (5)

yeah the brakes will need attention,even on the short drive home they were poor, very wooden feel, but I think 4 pots with decent pads, mintex 1155s or Performance Friction etc plus goodridge & Motul RBF660 fluid should be a worthwhile upgrade (with matching rear pads of course) and shouldn't break the bank cost wise,

JP4

iTrader: (12)

One your biggest weight reductions could come from doors, electric/glass windows, spoiler, seats.

Check out the Redline magazine Nov 09 issue (#148) on pages 34-41 which has a big article on weight reduction and gives a few suppliers' contacts on lighweight panels, lightweight seats and lightweight windows.

budd

iTrader: (5)

I've been reading the regs for the Subaru Cup and the minimum weight limit is 1250kg, that's with fuel and driver, I'm not sure if that weight is measured before or after the race, because you could get 25kg variation just from fuel used, either way subtract my weight 85kg + say 25 litres fuel to cover race distance, and we're left with a target weight for the car less driver + fuel of 1140kg, apparently this is not hard to achieve and the series has reduced the weight limit from 1300kg to 1250kg because cars were regularly under weight.
What's the official std weight for a Classic and where's the nearest weigh bridge?

sco8bystu

theres a weigh bridge at welbeck just before normanton sure you know where i mean

budd

iTrader: (5)

when I get the clutch done I'll have to take it over see what it tips the scales at,
clutch is ordered I've gone for an uprated organic kit I can change to a paddle driven plate later if required, looks a pretty straight forward job I'll get on with it once the clutch arrives.

budd

iTrader: (5)

yesterday made a start preparing the the car, I removed the rear seats and sound deadeneing from boot I'll move forward untill all the sound deadening is out then I can get it ready for the rollcage, I also started to fit the battery in the boot but seem to have lost my big roll of battery cable , can't find it anywhere, I think it was in the back of a Volvo T-5 I've just weighed in DOH!!!

budd

iTrader: (5)

OK weight loss program is on hold until I find out exactly how the car actually weighs, it's been pointed out that the min weight limit of 1250kg is quite high and that if I remove to much weight then I'll be under and therefore excluded from the series.
Appearently last year so many competitors were under the original 1300kg limit it prompted them to revise it and set a new min weight of 1250kg, obviously I'll still be removing all the sound deadening etc but I'll leave chopping doors, bonnet etc until I get a clearer picture of whats what.
Next job is the clutch, my replacement organic kit arrived to day so I'll get cracking with that over the weekend.

dunx

iTrader: (3)

Ballast ! Rip it all out !

You can add ballast as low as possible to aid the handling.....

dunx

ZippyBobby

change seats mine weight about 4.5kg each now old ones weigh a loads

budd

iTrader: (5)

LOL great minds think alike I've just been reading the Blue Book regarding ballast, my thinking is while it's been corner weighted apply the ballast for best balance.

Those are seriously light!!! my old Cobra Imola GRP seats weighed around 8kg and they were pretty light so nearly half that weight is a light seat the only FIA seats I seen that light are carbon Recaro jobbies and they cost more than I've paid for the car!!