The Range Racer

[Pig benis]

Munter said:

Posted in the last few days on Facebook.

Understeer appears to be an issue.

https://www.facebook.com/274988813211477/posts/609...

Ah ha, thank you

[Hub]

Pig benis said:

Munter said:

Posted in the last few days on Facebook.

Understeer appears to be an issue.

https://www.facebook.com/274988813211477/posts/609...

Ah ha, thank you

I see there's a newer video than that!

[charlie-5mkmt]

Hey all!

Apologies for not sending any updates on here recently! I haven't had any time to keep you all updated with what we have been up too!

Here is a quick update on whats changed and i shall write up something more complete over the next few weeks!

1) Its now RWD! With a modified transfer box we are now sending all drive to the rear, amazingly it didn't caused catastrophic electrical failure! We still have the old transfer box so its completely reversible but it seems like a good idea for some fun

2) we took it to curborough for a little test, feedback is.....it can now do skids but.....it very much wants to under steer still!

3) we crashed on our 3rd lap! in a failed attempt to provoke some over steer, we ended up with HUGE under steer which meant we has a slight bump with a wall. Everyone was ok and minimal damage to the range (headlight, bonnet & bumper and lots of electrical problems caused by a blown 60a fuse) Its very clear our week point is suspension set up, over sprung and over damped, we need a plan to fix that next.

[The Wookie]

We don't call that understeer, we call that 'Get fked with your request to alter trajectory'

[charlie-5mkmt]

The Wookie said:

We don't call that understeer, we call that 'Get fked with your request to alter trajectory'

hahaha! this lady is not for turning!

[SturdyHSV]

Understeer you say? Michelins on the front, LingLongs on the rear, what could possibly go wrong?

It does look fantastic on track, look forward to more updates

[MiniMan64]

Having seen the video it really didn’t want to make that corner did it?

[anonymous-user]

That had all the balance and poise of a three legged hippo on ice, and half as much speed

Is it as much unruly fun as it looks??

[Slow]

Have you thought about cutting the turret tops off and raising them by a few inches?

That way you would get some suspension travel with air in the bags but while being down low still.

[Yazza54]

It doesn't look over sprung at all, far too much roll. From the video of you hitting the wall it looks like it's just immediately flopping on its outside front and overloading it. Because it's a Roly poly car with a high CoG you need to control that weight transfer much better. I wouldn't go mad trying to induce oversteer by unsticking the rear until you've actually got that body roll somewhat under control, then go from there. Assume it's not just running whatever the standard geometry is either as it'll need a good chunk of neg camber front and rear.

Edited by Yazza54 on Tuesday 1st September 21:31

[Slow]

I think it is running with basically no air in the bags as it looks to be bouncing off the bump stops. If you had the turrets raised you could put enough air in for “standard” height on the bags but while being lower to the ground. Thus not hitting the bump stops and bouncing as much,

The current method for them to have it down low is to go in access height and pull a fuse I believe, might have changed since I last remember. This leaves the suspension and dampers compressed past the middle where it should be for normal body control.

At least this my thoughts as I am looking into getting strut spacers to bring my turret tops down for a better lift than my current method of just massively over inflating the bags. Without going to coils, custom turrets or shortened bottom mounts of the damper I don’t think there’s too much to be done handling wise.

Could obviously be wrong with everything I have just said.

[The Wookie]

Yazza54 said:

It doesn't look over sprung at all, far too much roll. From the video of you hitting the wall it looks like it's just immediately flopping on its outside front and overloading it. Because it's a Roly poly car with a high CoG you need to control that weight transfer much better. I wouldn't go mad trying to induce oversteer by unsticking the rear until you've actually got that body roll somewhat under control, then go from there. Assume it's not just running whatever the standard geometry is either as it'll need a good chunk of neg camber front and rear.

To be fair you want to run a car like that as soft as possible without it falling over itself on direction change or rolling off the camber. Plus I doubt the shell is that stiff so if you go too high with the spring rates or roll bars and it’ll just move something else!

I’d say the roll rate looks high though, probably not helped by the roll centres possibly having dropped more than the CofG with the lowering. Might even be below ground

I’d also say it looks underdamped and that it’s just bouncing in and out of the bump rubbers (or whatever the equivalent is in the internal profile of the air springs). A good bit of rebound to contain it will also help the roll rate too!

[Yazza54]

Yeah, it's rebounding/rolling and flopping over far too quickly. I'd get some adjustable bars on on it as it gives you loads of scope.

But as said above, if it's been lowered and all the geometry is fubar it'll cause loads of other issues. Ride height lowered without correcting anything else will obviously lower the roll centre (not always bad as long as it's not way below ground), it'll certainly have affected your roll camber curves.

So the post about it being over sprung and over damped, I would argue the opposite on both accounts. Hard to say much more though as I've no idea how it's actually set up and if it's bouncing off its bump rubbers and got geometry even more unfavorable than it began with it's no wonder if handles poorly.

I don't know how serious you are about this project or if it's just a bit of a laugh but the car needs some proper adjustable coil overs and bars on it to have plenty of scope to make it handle something like right.

Edited by Yazza54 on Tuesday 1st September 22:18

[Don1]

You do realise that it's being done by three chassis engineers?

[Yazza54]

Nope, that didn't come through in the posts and I haven't read the whole thread. Regardless, it doesn't make my opinion on the handling invalid.

Edited by Yazza54 on Tuesday 1st September 22:36

[The Wookie]

Don1 said:

You do realise that it's being done by three chassis engineers?

You driven a JLR mainstream product recently?

[C Lee Farquar]

The Wookie said:

You driven a JLR mainstream product recently?

I agree with Yazza, check the geometry. Unless it's adjustable, lowering with short double wishbones will significantly alter the camber.

I also agree that roll bars may be a solution, but not starting from where they are now.

[Don1]

The Wookie said:

You driven a JLR mainstream product recently?

Very good.

[RacerMike]

The Wookie said:

Don1 said:

You do realise that it's being done by three chassis engineers?

You driven a JLR mainstream product recently?

In fairness, there's a difference between Chassis and Vehicle Dynamics at JLR. The Chassis guys are component engineers. I don't believe these guys are in Vehicle Dynamics.....and I'd say that actually most JLR stuff steers pretty well!

[Munter]

RacerMike said:

and I'd say that actually most JLR stuff steers pretty well!

It's hard to test that when it's stationary on the side of the road though.
(Sorry is this not the "take cheap shots at JLR thread?" My bad.)