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spitfire front uprights (wishbone plans)
goodall - 22/11/06 at 11:07 PM

has anyone used these before?
if so do you have any demensions or drawnings for them?
also if anyone has used them, what did you use for the top ball joint? is the taper the same as on the transit trackrod ends?

the reason i ask is because we have two srcaped spitfires and i'm thinking of useing parts of them but with an audi 5 and a frod gear box

[Edited on 22/11/06 by goodall]


mookaloid - 23/11/06 at 12:06 AM

I personally wouldn't use them.

I used to have spitfires and heralds

Having had the bottom trunnions break (one at 70 mph) I think they are not a great design

If you do use them I would recommend buying all new components anyway as they seem to suffer from fatigue.

Cheers

Mark


3GEComponents - 23/11/06 at 10:17 AM

The Caterham upright is based on the Triumph part, but they've replaced the lower bush with a spherical bearing.


SaveTheDodo - 23/11/06 at 10:39 AM

Comparison of the Spitfire upright with the Cortina shows far superior suspension & steering geometry. This is why this upright was used in 2 F1 title-winning cars, the Lotus Elan & Europa, and the majority of Caterh*ms. (Guess who has previously scrapped a terminally rusty Spitfire!!). Thats the advantage of using them, now for the disadvantages!!

While poor maintenance can lead to failure (part of the reason is that the upright is a wearing part as well as the trunnion), the real obstacle to using them in a Locost is they are fundamentally incompatible with a chassis designed for cortina junk!!

As the castor angle is produced by angling the lower wishbone front to rear ( as the trunnions only move in 2 dimensions), this means a redesign of this part of the chassis, plus the wishbones need to be completely different at the outboard end as well.

That is before you realise that the roll centres need careful thought as the proportions of the uprights are so different! (And then you need to redrill the hubs for a Ford PCD, plus brake upgrades are almost impossible without paying Wilwood £400)

The list goes on and on....

I guess these complications are why Caterham has remained the leader of the pack for so long!! Almost everyone else has gone for ease of design over slightly better handling.

(But thats another argument....)

All the best

Andrew


cymtriks - 23/11/06 at 12:24 PM

Why is the geometry better?

Has anyone got numbers for-

Cortina
Spitfire/Herald
Sierra with a "button" upper ball fixture fitted

I did some calcs on a Cortina and Granada upright once that showed a huge scrub radius, something like 2 inches IIRC.


TL - 23/11/06 at 01:29 PM

HI Goodall,

If you do go Spitfire front end and want decent brakes, I have the following set up for sale which might interest you:

- a pair of GT6 uprights with:
- new bearings (bigger than Spit);
- refurbed GT6 calipers, spaced to go over...
- vented 266mm diameter discs (new),
- billet aluminium caliper brackets
- including aluminium hubs with Ford studs.

They will only fit inside 14"+ wheels, which coincidentally I have a set of 4 14"x6" 5 spoke revolutions for sale.

Let me know if you are interested.

p.s. Sorry for hijacking your thread & turning it into a for sale ad!


goodall - 23/11/06 at 03:17 PM

how much would you be lookin for them? i don't want to spend too much since i already have some uprights and it would seem sorta foolish to spend alot of money on another pair, but maybe it might be worth it for better breaks


goodall - 23/11/06 at 03:26 PM

thanks for the insight andrew. i think i will go ahead and use then and posibiliy use spherical bearings on the bottom and still not sure about the top.


Bob C - 23/11/06 at 04:30 PM

It's a fairly ordinary ball joint at the top (quite nice if you want camber adjustment...)
I don't know how you'll do AWD with spit hubs!
Bob


goodall - 23/11/06 at 04:45 PM

its a ball joint alright, but i'm not sure how it would be nice for camber adjustment as its a cup held in place by two bolts to the top wish bone, i can't see any easy adjustment in it myself

nah i've dropped the idea of awd now because it appears to be too difficult.


Andy S - 23/11/06 at 05:03 PM

The top ball joint - use a lada FSO Fiat 124 track rod end.

The Caterham Rose joint type upright is different to the trunion type.

Brakes - I have GT6 discs with Princess 4 pot calipers on mine inside 13 rims

Drilling for Ford PCD - get Caterham hubs or alloy type there are loads of options.

Lower wishbones - look at the Lotus/Caterham layout.

The biggest issue with the uprights failing is the mistake of using grease rather than hypoy in the trunnion.

Cheers

Andrew


britishtrident - 23/11/06 at 07:17 PM

The trick is to get a Marina or Dolomite or early Tr7 Rear axle -- all been covered great detail many many times in this forum do a search on the forum.


Bob C - 23/11/06 at 07:42 PM

***its a ball joint alright, but i'm not sure how it would be nice for camber adjustment as its a cup held in place by two bolts to the top wish bone, i can't see any easy adjustment in it myself ***
yep that's the one - you can move the pivot point fore & aft by insertion of spacers e.g. washers!
Bob