Fury Chassis setup 'Wandering'

For general chat, questions etc about cars designed by JP - the main forum
User avatar
tims31
Posts: 30
Joined: Mon Apr 14, 2014 6:38 pm
Name: Martin
Location: Spalding, Lincolnshire
Contact:

Fury Chassis setup 'Wandering'

Postby tims31 » Tue Aug 01, 2017 4:10 pm

HI,

Managed to get out and drive mine a bit over the last few days and now running reliably.

I have had the chassis set up as per the recommended settings by Steve at Fury but I am finding the car wandering around at the front and it is a real effort to mainatin a straight line as I am having to make corrections all the time and above 60 it really is hairy.

The rest of the handling is good but the wandering from side to side is quite off putting.

Has anyone else found this and what would you recommend to eliminate it. I have just had it setup for tracking, corner weighing, castor and camber but hasn't reall made any difference to the wandering.

User avatar
peter030371
Posts: 397
Joined: Wed Jul 01, 2009 1:37 pm
Name: Peter Smith
Location: Hawkhurst

Re: Fury Chassis setup 'Wandering'

Postby peter030371 » Tue Aug 01, 2017 5:18 pm

Might help if you tell us what Steve recommended. Also what tyres and pressures are you running?
Editor of 'The Proper Job'

User avatar
tims31
Posts: 30
Joined: Mon Apr 14, 2014 6:38 pm
Name: Martin
Location: Spalding, Lincolnshire
Contact:

Re: Fury Chassis setup 'Wandering'

Postby tims31 » Tue Aug 01, 2017 6:47 pm

Ok,

Tyres are Yokahama A539's @20psi 185/60/13"

Protech Shocks with 180-225 Springs Front, 6 clicks
130-180Lb spring rear 5 clicks

Front Toe in 0.5mm, 2 degree negative camber
Rear Toe in 0 degrees, 0.5 degree negative camber

Caster on front is 4 degrees negative

I have 2 shims behind the rocker arms and three in front if that helps.

User avatar
adithorp
Posts: 1119
Joined: Thu Jul 02, 2009 8:26 am
Name: adrian thorp
Location: Hyde, Manchester

Re: Fury Chassis setup 'Wandering'

Postby adithorp » Tue Aug 01, 2017 9:00 pm

After a lot of playing with mine I'd suggest for road use (and it's from memory)...

Put more castor on. Move at least one shim forward, so it 4+1. 4deg isn't a lot and will be a lot less twitchy around 7deg.

Take of some front camber off. 1-1.5deg max camber.

Front toe should be about right but you could try another 0.5mm toe in.

Rear want's to be 0.5mm toe in and about 1deg neg camber.

Ride height should be around 120mm under the front chassis member. Check the front lower wishbones are roughly horizontal along a line between the inner mount bolt and centre line of ball joint (not along actual wishbone arm) or a little down at the outer end. You also need about 20-30mm of rake IE. the rear 2030mm higher than the front measured at chassis rail behind seats.

Springs... What do you mean by 180-225 and 130-180? Which do you have?

After that you'd need to look at bump steer but that's a whole chapter on its own.

User avatar
tims31
Posts: 30
Joined: Mon Apr 14, 2014 6:38 pm
Name: Martin
Location: Spalding, Lincolnshire
Contact:

Re: Fury Chassis setup 'Wandering'

Postby tims31 » Tue Aug 01, 2017 11:16 pm

Cheers Adi, will have a look at that tomorrow

User avatar
adithorp
Posts: 1119
Joined: Thu Jul 02, 2009 8:26 am
Name: adrian thorp
Location: Hyde, Manchester

Re: Fury Chassis setup 'Wandering'

Postby adithorp » Tue Aug 01, 2017 11:26 pm

And the spring rates?

User avatar
tims31
Posts: 30
Joined: Mon Apr 14, 2014 6:38 pm
Name: Martin
Location: Spalding, Lincolnshire
Contact:

Re: Fury Chassis setup 'Wandering'

Postby tims31 » Wed Aug 02, 2017 9:22 am

Sorry Adi, I got mixed up with the spring rates that steve had sent me and posted up the range rather than the actual spring rates.

The fronts are 180lb and the rears 150lb

Having had a read of various recommended methods for setup, where I had the car setup they said the car has 4 degrees negative castor but reading seems to suggest that more negative castor will increase the likelyhood of wandering??

User avatar
adithorp
Posts: 1119
Joined: Thu Jul 02, 2009 8:26 am
Name: adrian thorp
Location: Hyde, Manchester

Re: Fury Chassis setup 'Wandering'

Postby adithorp » Wed Aug 02, 2017 12:43 pm

Negative castor would make it twitchy but I can't believe you actually have negative castor on a Fury. That'd mean the top ball joint was ahead of the bottom one and I'm pretty sure thats not possible with the chassis pick-up points. To achieve it the mounts would have to be in the wrong place. I suspect they've mixed up pos+neg and if they don't get that, then what else is wrong. Moving the rocker back gives more positive castor, less twitchy and more self centering.

I've got (from memory as I can't find where I wrote it down after checking) 6 or 7deg positive with the rockers almost fully back. I've tried more and less but thats what feels best to me.

I've checked my notes and before I fixed my bump steer I had...
Front toe-in 1mm and Camber 1.25deg negative
Rear toe-in 0.5-mm and camber 1deg negative


However after I corrected the bump steer. There was 6deg of change between full droop (in) and full bump (out) :shock: Now theres almost none. I had to make it twitchier after so now have...
Front 2mm toe out and a bit more neg camber at both ends.
The bump steer did make it twitchy but not massivly so and mostly on very uneven raods. I didn't sort it for 5 years so it can't have felt that bad.

It's also worth checking how free your steering is as that can make it feel odd and people have found new racks to be over tight on the pre-load and it hampers self-centering.

Those springs rates are OK then. Maybe a bit soft but that can come down to preference and I doubt it'd cause what you describe. It's what Jeremy originaly specified but people have gone a bit stiffer over the years. I started with 210-160 went to 210-180 and am now on 180-160 but with progressive bump stops. It's taken me 8 years to get there though ...and I'm still fetling.

User avatar
tims31
Posts: 30
Joined: Mon Apr 14, 2014 6:38 pm
Name: Martin
Location: Spalding, Lincolnshire
Contact:

Re: Fury Chassis setup 'Wandering'

Postby tims31 » Wed Aug 02, 2017 2:35 pm

Thanks Adi, I thought I was going mad as the paperwork for setup said negative castor but I was sure it was positive, thanks for confirming that and yes the top ball joint is behind the lower meaning it is positive. I have moved the rocker back another spacer so have four in front and one behind. Hopefully will get out and try it tomorrow if it ever stops raining here.

Depending on how that is I may add a little more toe in on the front whch may help to settle it down too.

yes the steering rack is new so may bed in a bit after some use.

I will report back when I've had a bit more time testing.

Thanks

User avatar
pigeondave
Posts: 332
Joined: Wed Oct 05, 2011 4:16 pm
Name: David Malenczak
Location: Brighton

Re: Fury Chassis setup 'Wandering'

Postby pigeondave » Wed Aug 02, 2017 3:16 pm

Have a fiddle with the shocks.

I have protec's they are set on the mid range of the adjustment. The car came out of the factory with them wound up to about what you said.
The fronts are on zero or 1 click the rears are on about 3 i think.

While on tour i was no way confident with the car, one of the fellow tourers said that the back of my car was skipping sideways in the corners. I adjusted the clicks and it made the car a lot more pliable and fun to drive


Return to “Jeremy Philips Cars”

Who is online

Users browsing this forum: No registered users and 4 guests