R32 Gts Vs Z32 Alloy Front Knuckle

[craigy32]

soooo I've been searching for an answer to this for a little while... I'm putting in z32 alloy knuckles into my r32 gtst with a custom upper control arm etc.. the knuckle geometry looks identical- all measurements including king pin angle, steering arm length and ackerman, etc etc EXCEPT for one thing- the hub on the z32 knuckle is mounted about 15mm more forward than the r32 one..

my question is- how will this affect handling given all the alignment settings are the same? I'm kinda stumped! I've added a couple of pictures to help explain..

Thank you!

[craigy32]

ok i just found this...

http://www.super7thheaven.co.uk/Trail

[craigy32]

noone?

[GTSBoy]

Well, my only thought, without having to engage my brain hard enough to think about what it will do to various angles and so on, is that you will probably end up scrubbing the tyre on the inner guard liner if you also wind on any reasonable amount of caster. This because the wheels will move forward in the wells by both actions (more caster and your knuckle changes). I already have that problem with 235s on 8s just with caster adjustment wound up to max on some Tein radius rods.

[craigy32]

yeah that may be a problem! haha I am making a custom upper control arm though so i can hopefully give it more caster that way and it will also put the wheel further back as well..

cheers for the reply

[D.I.Y. Mik]

It may make it more twitchy too

If it was a bike you would really notice it,

You know how on a bike the fork angle and offset of the hub control the feel of the steering?

Well im thinking its going to have some of that effect too.

So what is the difference in strut angle from the z32?

Also that longer distance from the hub means the wheel has more leverage to work against the steering, and the steering has more work/load to steer.

Maybe a z32 rack would fix it?

You must be doing this for drifting?

Ps: i understand bike suspension but not cars.

Edited January 22, 2013 by D.I.Y. Mik

[Roy]

Bene there and tried it. Spent almost 2 months waiting for it all to be trial fitted and played with and was a no goer due to steering arms/tue road end locations all being screwed up with horrible results in bump steer. The thing is barely lighter so just scrapped the idea of having allow hubs all round

[craigy32]

oh true! how did you have it mocked up if you dont mind sharing? And where did the steering arm end up compared to the stock location?

[craigy32]

It may make it more twitchy too

If it was a bike you would really notice it,

You know how on a bike the fork angle and offset of the hub control the feel of the steering?

Well im thinking its going to have some of that effect too.

So what is the difference in strut angle from the z32?

Also that longer distance from the hub means the wheel has more leverage to work against the steering, and the steering has more work/load to steer.

Maybe a z32 rack would fix it?

You must be doing this for drifting?

Ps: i understand bike suspension but not cars.

cheers for the reply offsetting the hub further forward actually decreases the caster offset, but does this increase the scrub in some way? I'm not entirely sure..

z32 factory caster angle is set at 12-13 degrees and I know the r32 is alot less.. maybe 6? so I'm guessing they changed the hub offset to possibly lighten the steering? or do i have it wrong...

mine was 8.5 with 3.5 degrees of camber.. the silly upper arm on a factory 32 is on an angle so changing the length changes both the caster and camber..

hmm