38 replies to this topic

[FLD]

When I first bought my skip there was an opinion of 'set castor to the max'. Which I've always done. I just thought I'd challenge that opinion and ask why? Eg if doing so gives me mis matched castor should I adjust the shims to match the castor side to side or just max it out as the wheels are tied together with the rack!? What I'm trying to gauge is the importance of accurately set castor and I need some input from someone who knows. Scuffers??! Sent from my iPhone using Tapatalk

[TFD]

Interesting question. Caster helps with cornering/straith line driving. More caster is better strait line stabbility, less caster should be for better turn in. Trollycar at the mall has little caster and responds directly to movement, Easy rider harley with the long front wheel has more caster and drives better in a strait line. (If you allready knew this, sorry). Now since it affects turn in I would think you want left and right at the same level so steering is the same in either corner. I have l/r 4.05 / 4.21 degree is caster, which is a bit more then usuall in a normal geo (3.8ish). Right side is also a bit more but I think this is within marge. I dont have the feeling I should reduce caster on my setup, but I do more highway and b-road driving atm. More info is allways good.

[Exmantaa]

If I remember correctly; caster also has to do with "camber gain" in cornering. (That's also how they measure it during a geo.)

 

So not only to do with straight line stability... 

[Tony H]

Also makes the steering heavier, and will want to self centre more.

 

 

[Nev]

If I were you I'd stick with OEM settings Matt, lots of experience and talent went into setting the base car. As you drive it on the road, set it up for the road IMO (as per OEM settings).

 

Castor is the least influential day to day geo setting IMO. I didn't notice any change in my handling when I increased mine.

 

Edited by Nev, 30 August 2016 - 11:03 AM.

[D-DAWG83]

MBR machined down my steering arms to give more castor. He said it will make the steering a little heavier, but other than that, there are only gains to be had, no losses.

[Nev]

MBR machined down my steering arms to give more castor. He said it will make the steering a little heavier, but other than that, there are only gains to be had, no losses.

 

That machining would affect camber, not castor old chap. Castor is adjusted by moving the shims fwd/backward on the upper wishbone bolts.

Edited by Nev, 30 August 2016 - 11:02 AM.

[D-DAWG83]

Doh, il go back in my box.... Lol

[Nev]

Scuffers??!  

 

Don't invite the devil to the dance !  

[stu8v]

It was night and day difference when I moved mine to the maximum position by redistributing the spacers.

 

I now have a lot more confidence.

[Nev]

It was night and day difference when I moved mine to the maximum position by redistributing the spacers.

 

I now have a lot more confidence.

 

Really, what changes did you notice?

[FLD]

If I remember correctly; caster also has to do with "camber gain" in cornering. (That's also how they measure it during a geo.)   So not only to do with straight line stability... 

That's interesting. That puts an importance on matching them side to side then, despite the sides being linked by the rack. Sent from my iPhone using Tapatalk

[Exmantaa]

 

It was night and day difference when I moved mine to the maximum position by redistributing the spacers.

 

I now have a lot more confidence.

 

Really, what changes did you notice?

 

 

Also very curious to what "night and day" difference you experienced... During normal road driving or on track?  

[Tony H]

I will contrast that with my experience of moving from 2+2 to full castor and couldn't tell the difference.

[stu8v]

It was night and day difference when I moved mine to the maximum position by redistributing the spacers.   I now have a lot more confidence.

  Really, what changes did you notice?

Instant stability, more feel and better weighting of the steering. Instant win for me, before it felt slightly floaty. All this is with the same toe settings as before front and rear. (I had to reset them)

[Exmantaa]

 

 

It was night and day difference when I moved mine to the maximum position by redistributing the spacers.   I now have a lot more confidence.

  Really, what changes did you notice?

Instant stability, more feel and better weighting of the steering. Instant win for me, before it felt slightly floaty. All this is with the same toe settings as before front and rear. (I had to reset them)

 

 

I assume you went from 2-2 to a 3-1 shim distribution? (as you normally need minimal 1 rubberised shim at the uper "front-rear" position...)

[Andrew aka Stuwy]

If I were you I'd stick with OEM settings Matt, lots of experience and talent went into setting the base car. As you drive it on the road, set it up for the road IMO (as per OEM settings).

 

Castor is the least influential day to day geo setting IMO. I didn't notice any change in my handling when I increased mine.

 

 

don't you only drive on the road as well?

 

telling him to stick to OEM settings and then saying you did something different is a bit contradictory  

[Nev]

 

If I were you I'd stick with OEM settings Matt, lots of experience and talent went into setting the base car. As you drive it on the road, set it up for the road IMO (as per OEM settings).

 

Castor is the least influential day to day geo setting IMO. I didn't notice any change in my handling when I increased mine.

 

 

don't you only drive on the road as well?

 

telling him to stick to OEM settings and then saying you did something different is a bit contradictory  

 

 

I run slightly different geometry to OEM as I have lots of non standard parts on my car, like different hub carriers, different wheels, substantially more tyre to take advantage of, more overall weight, different shocks, abnormal front/rear spring delta, different steering arms, more front axle loading, higher front ARB stiffness, much higher floating mass at the front etc etc.

 

His car is pretty standard I think, hence my advice is not contradictory, but different due to our vastly different parts & weights.

 

Anyway, my settings are pretty close to OEM, the only main difference is that I have 0.5 degrees of neg camber on my fronts with a bit more toe out  and a bit more toe in on the rears.

Edited by Nev, 31 August 2016 - 02:14 PM.

[harboged]

I'd like to change to full castor when doing a suspension refresh this winter but I'm planning to use standard bushes, not poly bushes, meaning that I need to keep the snubber washers at their original positions and won't be able to run full castor.

 

So I'm wondering whether it would be OK to replace the two affected bushes with poly bushes in order to run full castor, and use standard bushes for the rest? Or perhaps replace all four top bushes to poly ones? Or is mixing standard bushes and poly bushes bad?

 

I'm aware of the pros and cons for each bush type.

 

[Rosssco]

 

 

I assume you went from 2-2 to a 3-1 shim distribution? (as you normally need minimal 1 rubberised shim at the uper "front-rear" position...)

 

 

Is 2-2 (presume 2 in front / 2 in rear) the standard setting?

 

Alternatively, I presume increasing the castor mean = 1 (in front) 3 (in rear)?