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datahar
5th July 2012, 03:47 PM
Hi there,

After longingly reading the book for more than a year now, I have decided to finally build this thing!

I have sourced (but not bought yet, so not too late) 2mm thick steel, enough to leave me with a confortable amount of spare, for £97 inc vat delivered
With the extra weight this will cause the entire body will be GRP to try and compensate.

I am aiming for a new plate build, but am wanting to keep to a budget, I have a motorcycle engine I was hoping to get reconditioned for the build (would the engine and gearbox be allowed for a new plate?)
Keeping the sequential gearbox, so I will be fabricating a paddle shift system.
Reverse I will be handling electrically.

The biggest headache I am having in the planning stage is the rear axle.

Rotating the engine 90degress, and a spline adaptor to a propshaft, then propshaft to a LSD sounds straightforward enough, but not cheap. Reverse wise would be a sprocket between 2 short propshafts connected via chain to a 20hp electric motor

Or I could stay chain driven (this sounds cheaper), I have seen Chain converted LSDs but was wondering if this was strictly necessary? Is a diff required for an IVA?

Could I go down the route of a solid axle with sprocket attached? (I am not planning on racing this car), this way I could have the reverse sprocket on there too, this certainly sounds easier and cheaper but I don't want to kill myself for the sake of a few £££s

Any thoughts and suggestions would be really helpful

Kind Regards

Jimmy

will_08
5th July 2012, 04:47 PM
I don't have a clue what your on about (you obviously do!), but welcome and good luck! :D

flyerncle
5th July 2012, 06:06 PM
Make life easy,sierra diff with reverse sprocket on diff and forget a long chain drive,impratical nigh impossible.

martinl
5th July 2012, 06:15 PM
I think when i have been looking through blogs on the motorbike engine builds, i came across someone that used what looked like an old starter motor that when activated, used in the same way that a starter motor turns the flywheel if that makes any sense

ayjay
5th July 2012, 08:40 PM
Anyway welcome to the forum .
Dont be afraid to ask theres always someone done it or tried it before.

Where are you based by the way?

loony
5th July 2012, 10:41 PM
Welcome another BEC enthusiast :)

OK - maybe I'm not advanced builder, but... I had to do my homework because my budget is tight.
I think that rotating engine 90degress and sprocket adaptor it's the cheapest option. I'm making my own sprocket adaptor from old bike sprocket and... steel donut finished on lathe. Then 2-part propshaft made to fit - diy or by professionals.
Reverse is made from "sandwich" reverse gear (mine is laser cut) and starter motor form VAG (counterclock rotation).

Depends on engine - you need right diff ratio to get compomise between max speed and acceleration, but as the diffs are interchangeble you can always change it later.

Remember - don't hesitate to ask, we are all here to help one another :)

alga
5th July 2012, 11:21 PM
I have sourced (but not bought yet, so not too late) 2mm thick steel, enough to leave me with a confortable amount of spare, for £97 inc vat delivered
With the extra weight this will cause the entire body will be GRP to try and compensate.


AFAIK ~1 mm aluminium is marginally lighter than GRP panels!

datahar
6th July 2012, 12:05 AM
Hi guys

Thanks for all the replies, to answer the questions (in no particular order because I'm on phone and can't see them whilst replying.

I'm in south cumbria England

That's interesting I didn't think aluminium would beat grp, think I'll stick to grp though, I want to add my own touch to the styling and uluminuim may be beyond me (or my budget)

Speaking of budget rotated engine and prop shaft if it, who needs a new plate anyway I'll Q it up and keep costs down

The motor to flywheel sounds interesting, I take it spins the engine in reverse? Wouldn't that be bad? Or have I bitten the wrong end of the stick.

I will have to sketch up my designs, going for detachable gullwing doors (a roof is the girlfriend's only requirement to this) so I'm thinking a pop up rear canopy with attachable t bar then doors, all to be stored in car, so guess I don't need to make a boot...

My welder and wire came today, so I can get practising until I get a garage to start things

loony
6th July 2012, 07:25 AM
Hi guys

The motor to flywheel sounds interesting, I take it spins the engine in reverse? Wouldn't that be bad? Or have I bitten the wrong end of the stick.



Only propshaft and gearbox spins reverse. (all depends where you mount starter motor)
It looks like this:http://www.youtube.com/watch?v=7GfBVKb60Fg
And works:www.youtube.com/watch?v=ugTB6muh-qE