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Scratch built spaceframe
Amos08 - 22/10/17 at 02:26 PM

Hello everyone,


I have been planning on starting a road legal scratch built mid engine space frame project for some time now.

I have searched all over google but not much help and havent got my head into the iva manual.

The base car will be either a vauxhall nova / corsa, with a space frame chasis running vx220 wishbones hubs driveshafts, with a z20let engine mid mounted from an astra gsi, steering rack, arb and all of the clocks looms and ecu from an astra gsi.

I have the below questions before i even think about starting.

1. Because it is completely rebuilding the car i know i will need an iva test to keep it legal. What are the iva requirements for a scratch built space frame? Im not a novice welder and have structural design qualifications (buildings unfortunatly ha). Do they test the design or the welds or anything? I wont need it to msa specs. Is it even possible to put an “amature” built chasis through an iva?

2. Because its an exisitng car shell i dont think il have a problem with radiuses ect, all the lights are already e rated ect. Do they test radiuses underneath the car?

3. I want to dona flat bottom, can you run fuel lines through the cabin to the engine in the back? Same with coolant and brake lines.


Let me know your thoughts

Cheers

coyoteboy - 22/10/17 at 04:31 PM

I'm going this route. As far as I can tell there's no requirements other than appearance of good quality welds and no requirement for analysis but if it looks like it's a flimsy mess they'll probably reject it. I think there's side impact protection requirements but they're minimal. There's no roll-over protection requirement, which is, quite frankly, nuts - so that guides you as to how stringent the testing is.

theconrodkid - 22/10/17 at 04:56 PM

have a look for pics of any Jeremy Philips midi,s J15 ? and take it from there.
i have an MGF going cheap, that would be ideal for your oily bits

Amos08 - 22/10/17 at 04:57 PM

quote:
Originally posted by coyoteboy
I'm going this route. As far as I can tell there's no requirements other than appearance of good quality welds and no requirement for analysis but if it looks like it's a flimsy mess they'll probably reject it. I think there's side impact protection requirements but they're minimal. There's no roll-over protection requirement, which is, quite frankly, nuts - so that guides you as to how stringent the testing is.

Thats mental! But will make the design easier ha. When i read the iva manual, what i could gather, was that you could build a space frame aslong as it basicly contained a roll over cage to the iva requirements. So a cage with suspension welded to it pretty much, the majority of the construction to the cage will be CDS, the rest t45 and square stuff for the base

Amos08 - 22/10/17 at 05:02 PM

quote:
Originally posted by theconrodkid
have a look for pics of any Jeremy Philips midi,s J15 ? and take it from there.
i have an MGF going cheap, that would be ideal for your oily bits

Il take a look! I wanted tonise the vx220 suspension as its double wishbone! Should mean in the future i could make some adjustable a arms if needed. And it keeps everything vauxhall which my ocd loves ha

Amos08 - 22/10/17 at 05:06 PM

My first initial design in my head is similar to the below build thread however of a new shape mini (another one of my obsesions apart from vauxhalls). Instead of having the “cage” portion welded to the square bar, the cage will be one peice from cds

https://www.bimmerforums.com/forum/showthread.php?1949940-Mini-Cooper-Build

[Edited on 22/10/17 by Amos08]

coozer - 22/10/17 at 05:29 PM

Im going down the Midlana route, all done and tested...



The book guides you through all the chassis construction.

[Edited on 22/10/17 by coozer]

Toys2 - 22/10/17 at 05:34 PM

My advice is NOT to assume that production car parts/design will automatically pass IVA

For example some production cars have rear fog light positions that don't look as though they would pass
and don't forget that regs may have changed since the days of the Nova/Corsa

The IVA manual isn't that scary if you work through it section by section

froggy - 22/10/17 at 05:37 PM

Have you driven a vx220 turbo ?

theconrodkid - 22/10/17 at 05:45 PM

http://www.locostbuilders.co.uk/viewthread.php?tid=179267

Amos08 - 22/10/17 at 06:01 PM

quote:
Originally posted by theconrodkid
http://www.locostbuilders.co.uk/viewthread.php?tid=179267

Do you think the chasis would fit under the shell?

Amos08 - 22/10/17 at 06:02 PM

quote:
Originally posted by froggy
Have you driven a vx220 turbo ?

Yes i owned one for abit

Amos08 - 22/10/17 at 06:08 PM

quote:
Originally posted by Toys2
My advice is NOT to assume that production car parts/design will automatically pass IVA

For example some production cars have rear fog light positions that don't look as though they would pass
and don't forget that regs may have changed since the days of the Nova/Corsa

The IVA manual isn't that scary if you work through it section by section

There will more than likely be something that doesnt confirm, however it is a good starting point, something like a foglight position can very easily be moved, then moved back afterwords lol
Its the little things, like fixing cables to the frame ect that i need to have a look at. Also how to fix the body to the frame. Whether to make the whole body removable. Or just a rear clamshell

Amos08 - 22/10/17 at 06:48 PM

quote:
Originally posted by froggy
Have you driven a vx220 turbo ?

Just noticed you said turbo! I owned the 2.2 so not as good lol

froggy - 22/10/17 at 08:19 PM

Kimini book by the same chap who wrote the midlana book is worth getting for the what you plan to build . I copied the rear suspension for my mid engined Reliant with a Saab turbo 2.3 in .

[URL=http://s144.photobucket.com/user/froggy_041/media/2c290abc.jpg.html][/U RL]

Took a lot of development to make it a reliable car for track use and you really need to get the roll centres in the right place before working on Spring and anti roll bar as you will be carrying a lot more weight higher up than an Elise, 220, mr2 etc with a steel shell with lots of glass

theconrodkid - 22/10/17 at 08:55 PM

quote:
Originally posted by Amos08
quote:
Originally posted by theconrodkid
http://www.locostbuilders.co.uk/viewthread.php?tid=179267

Do you think the chasis would fit under the shell?


the pics are just to give you an idea how it should look, you can adjust the dimensions to suite the body

Amos08 - 22/10/17 at 09:38 PM

quote:
Originally posted by froggy
Kimini book by the same chap who wrote the midlana book is worth getting for the what you plan to build . I copied the rear suspension for my mid engined Reliant with a Saab turbo 2.3 in .

[URL=http://s144.photobucket.com/user/froggy_041/media/2c290abc.jpg.html][/U RL]

Took a lot of development to make it a reliable car for track use and you really need to get the roll centres in the right place before working on Spring and anti roll bar as you will be carrying a lot more weight higher up than an Elise, 220, mr2 etc with a steel shell with lots of glass


I plan on having the shell as low as i can get it to help, do you think id get away with adjusting the positions of the vx220 wishbones to change the roll centre, or use a completely new design from scratch? Got any pics with the shell off?

Amos08 - 23/10/17 at 02:34 PM

quote:
Originally posted by froggy
Kimini book by the same chap who wrote the midlana book is worth getting for the what you plan to build . I copied the rear suspension for my mid engined Reliant with a Saab turbo 2.3 in .

[URL=http://s144.photobucket.com/user/froggy_041/media/2c290abc.jpg.html][/U RL]

Took a lot of development to make it a reliable car for track use and you really need to get the roll centres in the right place before working on Spring and anti roll bar as you will be carrying a lot more weight higher up than an Elise, 220, mr2 etc with a steel shell with lots of glass



Is there a way to adjust the roll centre on the fly?