Hi all,
Another new product just in. Pic attached below. CNC machined from aerospace spec. ally and anodised to precent corrosion. Offered at about 50% of
MK/Luego price.
Order at www.gtstuning.co.uk
Kind regards,
Darren
Rescued attachment mushroom.jpg
Nice!! was jus gonna buy a set of ebay there, made from alu. Glad i didnt now. Gonna get me a set of those bad boys instead
Darren, anymore offers on alloys for locost? Thanx
Do these fit granada uprights?
Darren,
Is the balljoint hole off-centre to allow adjustment? If not (which from the pic doesnt look like it is), can you do off-centre ones?
I presume its tapered for transit drag link?
Cheers.
Knowing Darren it will be offset, might just be the picture.
No the hole is on centre.
Working through the design of the front suspension i figured out that the range of adjustement that you got from having it off centre was so small
that it was pointless having it. Off centre makes it far more expensive to make and more likely to alter during use (and come loose) so i went with a
concentric one. If you use a 19mm offset wishbone you get the 5.3 degrees castor that you require.
Kind regards,
Darren
Thats ok then, cos my hole is in the centre too
but as they r not offset... maybe not
ISTR the offset/non offset issue being discussed at length before.
I think the fact that offset ones are adjusting 3 things at once....castor, camber and KPI...made them less desirable to some people...
Can't recall the overall concensus though, despite it going on a long time...
As i have CAD designed the entire suspension on our car then run it through the 3D kinematic analysis at every adjuster position i can tell you that
the castor adjustment is negligable, the camber adjustement is better done with my new camber system, and it effects KPI not a jot.
You can pay £47 for it to be 6mm off centre and get no benefit if you like!
Kind regards,
Darren
Darren, we may be getting our wires crossed.
I'm saying that the offset hole will affect KPI by effectively moving the centre of the top BJ in and out relative to the bottom.
The fixed hole will not affecct it as it's in a permanent fixed location relative to the bottom.
Perhaps that's what you were saying too?
Hi Alan,
To correct myself the only adjustment with an eccentric hole is the amount of trail you get. The camber will change also. The KPI and castor
doesn't change as they are both related to the relative positions of the ball joint centres to one another and as they don't change because
they are fixed to the wishbone.
Kind regards,
Darren
but surely with the hole not central, you'll be effectively altering the dimensions of the upright (thinking of the mushroom as being part of the
upright rather than the wishbone), which as you say will lead to camber changes but due to the design of the upright, rather than the position of the
bj.
i know what I'm blithering about anyway, dont seem particularly capable of putting them it into words!!
EDIT - I'm sure it will alter scrub at least.
[Edited on 19/3/2004 by GO]
the crack is, rotating the mushroom (edit: an offset mushroom that is) can lead to camber changes. To get the camber back, you will have to screw the
camber adjuster one way or the other. This will change the king pin angle, assuming that KP is the angle between the wheel and a line between the two
ball joints, because the ball joint has been moved.
diagram to follow if required!
[Edited on 19/3/04 by JoelP]
I know what you mean Joel, and its a good point. The effect that KPI gives you though is the self centering forces due to the scrub radius, this
isn't effected by camber as it effects the wheel as much as the ball joint maintaining the scrub radius.
Fundamentally its OK both ways, point being you don't need either system over the other. Concentric is easier/cheaper to make and that gets
passed on to you the customer. Ideal is to seperate the adjsutments out so they do only one thing on each adjuster there by giving you good control
over the geometry.
The Sierra upright with a concentric mushroom gives suprisingly good geometry much better than people give it credit for and i think better than the
Cortina in the context of a Locost.
I obviously like the idea of having the wishbones made to give the correct castor, the concentric mushroom and my camber adjuster mechanism this way
you have nice geometry and can control it for each individual area of adjustment independently of the others.
Kind regards,
Darren
i agree darren, its not really needed. However, cos i bought a top bone and made my bottom one, i couldnt get the right camber via the top ball joint alone, cos the upper bone was too short for my set up. Fortunately, by spinning the mushroom round it is nearly right. I appreciate the point though, if money can be saved then why not! Need to re do my lower bones anyway, they are shoddy to say the least.
how are you meant to dial out the negative trail in the sierra front hubs with the hoes in the centre.
at least if you buy them from mk you know they do the gob right cos theyve been tried and tested.
Phil, castor, which affects trail can be set by wishbone design and then adjusted by wishbone shimming within the brackets.
quote:
Originally posted by GO
but surely with the hole not central, you'll be effectively altering the dimensions of the upright (thinking of the mushroom as being part of the upright rather than the wishbonei.........
quote:
Originally posted by dozracing
Hi Alan,
To correct myself the only adjustment with an eccentric hole is the amount of trail you get. The camber will change also. The KPI and castor doesn't change as they are both related to the relative positions of the ball joint centres to one another and as they don't change because they are fixed to the wishbone.
Kind regards,
Darren
Alan,
Another good point well presented!
Just goes to show what confusion it creates. Best keep things simple, god meant holes to go in the middle! lol.
Hows the Meerkat coming on?
Nice and timely change of tack...
But yeah I agree, I design machinery for a living and we try and have one seperate adjustment for each axis of adjustment...makes thing much
easier...
Meerkat is doing well, thanks...should have all my body plug painted this weekend...
quote:
Originally posted by Alan B
ISTR the offset/non offset issue being discussed at length before.
I think the fact that offset ones are adjusting 3 things at once....castor, camber and KPI...made them less desirable to some people...
==> You need about an inch of rearward offset to get your castor and a half inch per degree of camber. The rod end will give you your camber adjustment and the mushroom will probably not give you enough for full castor. As you dial in the mushroom both castor and camber will change.
jcduroc - 22/3/04 at 01:14 AMIMHO:
1. Make the wishbones to provide the 5º30' caster by offsetting the balljoints 19mm;
2. Shimming 1mm the wishbone bushings changes caster by 0º17';
3. Adjusting the top balljoint/Transit rod end (1.5 ppitch) by one full turn changes camber by 0º26'.
4. Centre the mushroom hole...
João
dozracing - 22/3/04 at 07:35 PMExcellent, so that all agreed then, on centre is OK.
What a relief, it would have been a right bugger to change 200 of the things!!