newbie questions re A Arm designs?

[danilo]

I'm baffled by the Book's front A Arm design, specifically the lower one.
When compared to a Caterham one it appears as seriously erm "Agricultural " :-)
Why does the lower shock mount so far inboard, requiring a slab of boiler plate to spread the subsequently levered forces?
And correct me if I've misread this, but when one draws force vectors the centre line of the shock doesn't intersect the tires' centreline.
As it .. Does.. in the Lotus, now Caterham design, be it Trunnions or spherical joint.
I can't have been the first to notice this.. clearly though it has not been 'upgraded' .. Is there a genuine reason why, that I'm as yet unaware of?

Thanks

[Talonmotorsport]

If you look at the sierra upright it's designed to clear the where the McPhearson should mount to, it's a compramised design to make the most of a one doner car equals one roadster. If you want to move the damper bracket further out just lose the sierra upright and use/fabricate some thing else.

[danilo]

Ahhh .. Thank You sir. A clear explanation.
Being in Canada there are NO sierras of any description so I'm spared that at least. Regardless, the Authorities prohibit ..any.. adulterations to uprights .
I do have Spit bits on hand though :-).
But the uprights would /will need bespoke stub axles to allow the use of Moderne 100 mm PCD wheels/brakes etc., as I want nothing to do with TR brakes/wheels
Bit of an expense/runaround to make workable, but then those things are 1/2 the weight of even the Miata uprights... Plus and it's a biggie, I already own them.
Sooo.. If I use the improved uprights then I can also build Caterham A Arms or simply buy the rascals ( a bit pricey, tho they do come complete)
Bit of bracketry redesign needed as well.
Seemingly nothing is simple, is it?

[vetteman1355]

[quote=danilo;67858].
Being in Canada there are NO sierras of any description so I'm spared that at least.

Find your self a Merkur XR4ti same a Sierra, lots of them in the wreckers yard out here on the westcoast, save yourself a bunch of work

Nigel

[danilo]

Really? At which wreckers? I thought there were maybe 6 of the things sold in Canada, as they weren't exactly 'popular' ...25 years ago.
Could be useful, although the Diffs are iffy in Caterhams.. as these are proving unacceptably Noisy contraptions. Seems owners who paid tens of thousands for their machines prefer quiet differentials :-)
Typically BMW diffs are currently being retrofitted to solve the problem.
I do like the bolt on CV joints. Although that's usually a German design.
Regardless there's No sticking mushrooms into the uprights AND passing BC Govt tech scrutiny. Important if you want a License plate or did you miss that part ? :-)

[vetteman1355]

There were six cars out in an Aldergrove wreckers not sure of the name as it was a buddy of mine who was there.
Regarding the hubs there is a guy who has already passed the inspection with this same set up so there should no issues, the garage in Ladner on the main drag is well know for getting cars through the inspection.

Nigel

[danilo]

Interesting Info.
There was a "mechanic" of sorts, apprehended :-) recently for 'approving' cars without actually seeing them.. ever.. all one needed to do was mail him the $$. Rebuilt wreck, stolen, it didn't matter at all.. Lovely.
A bit too Dodgy.
I see no convincing reason to fit bodged Sierra/Merkur struts or other bits even, when the Miata parts (all of them) are simply better suited for the intended purpose ..even over and above being legal to use?
Thanks for the thoughts though.