Is 700Kilo right for all up weight - fueled and ready to go?

Any ideas on weight reduction?

What would be realistic in weight saving?

No heated rear screen so polycarbonate repacement would be an easy saving.

Possibly removing the dash and fitting a digi dash (acewell type)

Carbon fibre or lower weight GRP front and rear bonets - existing rear pannel is very heavy.

Would replacing the A series with (for example) a K series result on weight saving?

All thoughts welcome

Regards,

Allen

I would say that looking at saving a bit in all areas would be the best way to save weight. seats, wheels, hubs, engine (flywheel).

I always think that the two best areas for weight saving are the flywheel and anything of the unsprung weight.

What are you taking the weight out for? This can affect the route that you take.

I would say with a Mk2, to keep the A series, otherwise you would need to change alot of the rear of the car.

And take the roof off!!!!

Long term plans - I'm coming from a 7 roadster with all up weight of 680Kilo and 155bhp. I'd like something similar with the GTM

I need something that's fun but more civilised.

More power and less weight = more fun

Not intending to do motorsport -just driving on the public roads and upsetting the other drivers

Realise light flywheel provides a double benefit and drilled disks and alloy calipers would be a good move. Don't have unlimited funds though

The bodywork on my mk1 is so thick and heavy it would be better suited as a boat.
My aim is to run a car that has 120bhp and weighs 500kg
I have removed the second skin from the rear section attached the boot to it then cut out all the unseen parts.
I cannot tell you the difference in weight but i can lift the new item on my own
The next thing is the roof.again i dont know the weight but have u tried carrying one.
I am also changing the engine, more power less weight.
I will let you know what difference it has made the next time it is on 4 wheels.

My thoughts would be sell the Rossa, and Buy a Coupe

You're right thunderossa about the weight of the rear bodywork, long term I might re-do the back end to fit lightweight led lights, join the boot and rear pannel together as you've done but make a mould and then do a lightweight moulding - perhaps as one peice rear hinged clam?

How do you plan to do the engine change - what are you thinking of using?

Take your point turbocox, coupe is lighter to start with - but I've also read people's rebuild details and the battle against the tin worm


I also find the coupe doors a bit small and the cabin claustrophobic -think the rossa looks better too

tin worm, or can of worms????

I cant use a coupe as i need the room behind the seats to fit the 1000cc thunderace engine
The subframe has gone and a spaceframe is well on its way
I can pick up the engine,unlike the Mini and the spaceframe is alot lighter than the Mini
The framework is attached to the rollcage hoop and the cage will be finished off
this is the only weight that i will add.
Once the car is up and running i will look at replacing the front subframe

Thunderossa, I'd be interested to see some photos.

Still long term plan but I'm thinking along the same lines with extending the roll cage but perhaps fitting a Kseries or a perhaps a ford sigma - you're right about the weight of the hardtop too.

I recon the bonnet (front) is pretty heavy too, remove the bonded on stiffening and join it to the front valance and hinge like a clam

One thing that always surprises me is the weight of the seats as mentioned by Tim above. This must be one of the easiest ways to lose weight and something lighter will no doubt be available on ebay. That depends, of course, on what you have fitted already - I have half leather ones from a Corsa SRi and they weigh a ton so I'm keeping an eye open for something lighter.

If you want a Rossa with a K series in it and a clam front, why don't you buy a K3?

I'm sure it would be cheaper.

Ive got to agree with Tim
We have spoken before about puting larger transverse engines into the mk1/2 cars and the engine bay is just to small.
If you cut the back off to fit the engine there would be nothing but plywood left
Choose your engine then look at which model it fits the best
Then ask advice from the members who have done it

I'm going to use a titanium bike can for a silencer, under 3lbs with removable baffles

It's quite possible any performance advantage gained by losing the hardtop would be wiped out by less effective aerodynamics

Reasons for not buying a K3

Apparently the K3 is even heavier - partly I guess due to the hydrolastic suspension?
Couldn't find one when I was looking.
My Rossa is tax exempt
Apparently, I like a challenge

Don't knock plywood, I'll mention the early Marcos and the mosquito

Yes much bulkhead modification is required but I'm sure it can be made good and loading from the diagonals down to the top of the suspension towers on the subframe can feed throung to a braced roll hoop - that's the plan.

Stick a turbo on the engine. You can get some serious power if you do it right. I would save loads of work on the car, so you can concentrate on getting the weight out of the car.

I think Neil philosophy of taking a bit of weight out of everything could be a good way to reduce the overall weight of the car.

Remember to take all the weight out evenly, so that you have a good balance on your corner weights. No good having a light car, if it handles badly!!!!