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Sierra lower arms
JoelP - 29/7/03 at 07:07 PM

I was hoping for some advice.

Im using sierra hubs on a proj, having made some lower wishbones i was considering cutting the ends of the old lower arms and welding the ball joint onto the new wishbone. dont laugh.

Thinking about it this doesnt sound to clever.

So do i do that anyway or use maxi/cortina ball joint? or what?

And then how do i get the hole on the hub bored to the right size?

Any help would be appreciated!

stephen_gusterson - 29/7/03 at 11:01 PM

you cant use the original joint as its not made for the loading. The sieerra takes the weight in the strut, not on the lower wishbone joint like a locost does.


atb

steve

James - 30/7/03 at 09:52 AM

You need to get the Sierra lower hole bored to the 'exact' taper of the Cortina/Maxi ball joint (they are the same taper).
If it's not exact then there will be an uneven loading of the balljoint which may cause problems.

I took my hubs to MK and got them to bore out the hole as they have the correct size reamer (it was only £7 per side).

The other option is Astra (I don't know which model) ball joints. I haven't tried them myself but Rory who runs the Lolocost stand told me that they fit and someone on here has used them.
To be safe (if you're gonna try this option) I'd take your hubs into your motor factors and trial fit them. Just make sure they fit well!!!

Hope that helps,

James

[Edited on 30/7/03 by James]

JoelP - 30/7/03 at 12:43 PM

thanx chaps, i'll ring mk now...

not too far away either!

maxi balljoints look easier to fit, so i guess thats the way forward...

thanks again.

JoelP - 30/7/03 at 01:14 PM

bar stewards quoted me 40 bar...

dag nammit....

stephen_gusterson - 30/7/03 at 01:38 PM

looks like the cortina joint mounts with 2 12mm bolts and 2 8mm bolts acording to mine.

maxi joints have just 2 8mm or is it 10mm bolts? must be ok I guess, but not as ballsy as the cortina....


atb

steve

Alistair Mc - 30/7/03 at 03:30 PM

If I recall a mk2 astra lower ball joint fits the sierra taper

JoelP - 30/7/03 at 08:43 PM

how sure are you? that would save a lot of effort if astra joints can be bolted on as well...

stephen_gusterson - 30/7/03 at 10:15 PM

is an astra also a mcphereson strut suspension?

If so, the lower joint wont be designed for taking main loadings.


atb


steve

Alistair Mc - 31/7/03 at 10:41 AM

have had the bearing apart the construction seems ok for locost, have used them on my car (not on road yet). I beleive MK uses astra lower joints (at least he did not sure now).

Alistair Mc - 31/7/03 at 10:43 AM

the only problem i had is that the threded part sticks too far out of the top, however this gives the extra depth to mount the mudgard mounts.

JoelP - 31/7/03 at 11:16 AM

right then. thanx all.

i'm gonna widen the bottom ones and use cortina bj.

as for the top, i wouldn't mind getting a whole wishbone cos tapping a thread seems bad news. question is, which company sells the best/cheapest strut replacement for a sierra, and who supplies an upper wishbone that is approx 6inch out from bush to bj?

also need bushes and brackets. i've checked out a few online site but no-one seems to make it easy to part with money! GTS do a few of the bits but couldnt find the part that u use as an upper mounting on the hub.

James - 31/7/03 at 04:35 PM

quote:
Originally posted by JoelP
right then. thanx all.

i'm gonna widen the bottom ones and use cortina bj.

as for the top, i wouldn't mind getting a whole wishbone cos tapping a thread seems bad news. question is, which company sells the best/cheapest strut replacement for a sierra, and who supplies an upper wishbone that is approx 6inch out from bush to bj?

also need bushes and brackets. i've checked out a few online site but no-one seems to make it easy to part with money! GTS do a few of the bits but couldnt find the part that u use as an upper mounting on the hub.


A few points to bear in mind.

If you have book wishbones then I wouldn't recommend Maxi ball joints. I don't like the way they mount only at the 'end' of the wishbone which is just two 15mm(ish) wide strips of 3mm. The Cortina BJ with it's 4 mountings is better for this type of wishbone. MK wishbones that use the Maxi BJ are structured differently at the end and are stonger.

JoelP,
RE: adapters:
Yes the MK strut adapters seem expensive but I'm pretty sure they are cheaper than Luego. Luego's though, are aluminium so presumably will weigh less and won't rust. MK's have the BJ hole off-set (I'm not sure if Luego's do) which means you can adjust castor and camber by turning the insert.

Re: wishbones.
If you use Luego's Locost or Velocity wishbones at the front then the track won't match the rear as Luego cut down the rear drive shafts (I believe). MK's would work for you- except that the wishbones are a little wider (at the bush end) than the book ones. Therefore you could use these if you're happy to move rails FU1/2.

Bushes:
I'd highly recommend you get them from whoever you buy your wishbones from- then you know they'll fit the bush tubes correctly. You might aswell get the bolts and inner crush tube from them too.

Brackets:
I'm not sure if any manufacturer supplies these separately. MK's ones atleast need to be a little wider to match the larger wishbone bushes though. I'm not sure about Luego- phone them.
Merlin (posts on this list) will make you a set of MK compatible ones- I bought mine from him.

I've only mentioned MK and Luego here as you can see- I'm not sure at all about Stuart Taylor or any other manufacturers.

If I was in you're position and was definately buying wishbones and had a standard chassis I would buy the whole lot from MK and be done with it. And then move FU1/2 and rail E.

Also, either way, you're gonna have to get your steering rack chopped and extensions made. Again, MK can do this for you.

Hope some of that helps and that not too much of it was incorrect!

James

JoelP - 1/8/03 at 12:23 PM

Cheers James lad, that all helps.

I'm not using a book chassis so FU wont matter, i havent yet put in the front top rail yet so that i could c how big the wishbone was gonna be.

I'm making the bottom ones so i dont feel like too bad a cheat! Cortina ball joint it is cos i bought one a while ago. when i finally get the damned plasma cutter working i'll mince up some 3mm to make the end bit!

Anyway, i'm off to mk in the morning to get plenty done, so i'll let you know how it goes!

ta.