AST 4100

[R29TJR]

Evening all,

I’m going to get a set of 4100’s however I’m not sure what rating spring to get or even what options offer yet.

The car is used for sprints & trackdays and I also use the car to get to track etc.

Any advice would be great.

Tom

 

[JB21]

9kg front/11kg rear and rarb ?

 

[JamesBryan]

Yeah 90N/110N would be a good start.

 

[Martin.]

I would go for 80/85 or 85/90.

Have used both setups. For me I'd say that anymore than that and the car is literally undrivable on the road without destroying your back. I don't even like driving mine now on the road but I put up with it for my local track (Brands).

That setup is very good on a track. Can combine it with a RARB for adjustability. Stiff in the dry, and unbolt it in the wet. Works an absolute treat.

 

[Usr117063]

After reading other threads I went for 90/110 and for road its perfectly fine. Im not sure why most people say they are too stiff but mine are very smooth and compliant, if mine was a full track/race car Id be more like 100/120.

I had 80/80 when I first got mine and it was unbearable soft (more the rears), turning the rebound up on the fronts just made them a bit bouncy and lost what makes asts so good.

If you take a wrong turn and end up down a farm road not fit for a dakar truck like I did the other day then yeah you wont have the best of times. But for driving to track which will probably be more motorway it would be fine.

 

[JB21]

As above I feel 8/9kg is to soft for track/sprints but it's subjective, I like a lively rear to get the nose in easily but some will find this a little too on the edge and prefer the safety of a softer more predictable set up.

I would go even firmer at the rear and thicker arb if mine was track only and trailered to the circuit.

Here's mine on 4100's, 9/11kg springs and whiteline arb...

 

[Usr117063]

I watched your video when I was deciding on my spring rates ?

 

[JB21]

I watched your video when I was deciding on my spring rates ?

There was definitely more time to be gained from that set up as well, this was the first and last time I got to try it at Oulton as it dropped a valve seat on the next track day in Feb and had to be scrapped, still makes me sad to watch, lol.

 

[JamesBryan]

There was definitely more time to be gained from that set up as well, this was the first and last time I got to try it at Oulton as it dropped a valve seat on the next track day in Feb and had to be scrapped, still makes me sad to watch, lol.

With more camber and those slicks, yours would have been sub 2 minutes no doubt i reckon.

 

[JB21]

With more camber and those slicks, yours would have been sub 2 minutes no doubt i reckon.

Yep that was the plan mate. Still an ambition to crack a 2min lap around there, not in the Skoda though, lol.

 

[JamesBryan]

Yep that was the plan mate. Still an ambition to crack a 2min lap around there, not in the Skoda though, lol.

Definitely would have cracked it with the Clio i think mate.

Niall was at 2:05 on AD08R's, i'd imagine slicks would be a fair few seconds up on that.

 

[R29TJR]

So I whimped our and went for 80/80 based on AST’s advice and if I’m not happy I can always change at a later date.

Next question

You guys running camber bolts?

 

[JB21]

Definitely would have cracked it with the Clio i think mate.

Niall was at 2:05 on AD08R's, i'd imagine slicks would be a fair few seconds up on that.

2:05 Nice. That should be doable in the VRS with a bit more power, front camber and balls ?

 

[JB21]

So I whimped our and went for 80/80 based on AST’s advice and if I’m not happy I can always change at a later date.

Next question

You guys running camber bolts?

Yeah front bolts mate. I had around -2.5 each side. Adjustable top mounts will give you more as well if needed.

 

[JamesBryan]

2:05 Nice. That should be doable in the VRS with a bit more power, front camber and balls ?

A bigger intercooler will help massively on that.

 

[JamesBryan]

So I whimped our and went for 80/80 based on AST’s advice and if I’m not happy I can always change at a later date.

Next question

You guys running camber bolts?

Will be adjustable top mounts and camber bolts for me with BC's.

 

[R29TJR]

Also I'm going with PMS topmounts but do AST coilover have a standard M14x1.5 thread or M12x1.5 thread?

Thanks again in advance.

Tom

 

[Usr117063]

My 4100s have slotted holes for camber

 

[Simon@ASTUK]

The top slot on the damper is elongated for camber.

It really is personal preference on the springs as we have seen already in this thread. As you can imagine we speak to customers on our hugely popular Renault kits daily. The variation in usage is quite broad, we have a few customers up at 120 rear, some with ARB, some without, riding on the road. We have a very fast road race customer with a soft setup, and likes the car really neutral. We will usually recommend on the softer side of things wherever road use is involved. We recommend 80/80 a lot, plenty of customer heading out to the ring, and running airfield days, driving to the trackdays etc. If they are regularly racing at Silverstone and Donington etc you can go stiffer as you can imagine, they are entirely different type of tracks. However beware of going too stiff especially on the front.

Ultimately your driving style will make your choice for you.

Simon @ AST Suspension UK

 

[Usr117063]

@a17vts any updates??

 

[bashracing]

I think you've chosen wisely at 80/80,
On a 1 minute hillclimb you need compliance in the suspension otherwise the (cold) tyres loose lateral traction and just skip across the tarmac,
I've always set up my hillclimb cars as with spring rates soft as possible and controlling roll stiffness with higher damping rates and thicker anti roll bars.

eg, the micra runs
32n front springs revalved konis and a 22mm ARB
38n rear spings Saab estate dampers and a 22mm ARB
fair enough the car only weighs 680kg but that's 70% the weight of a well prepped clio road going hillclimber

 

[R29TJR]

@a17vts any updates??

So I went with 80 front & rear and ended up going with the AST mounts. They are much more however as the car is purely for track I thought I may as well go for a set up with the most adjustment, which the AST offers.

I think you've chosen wisely at 80/80,
On a 1 minute hillclimb you need compliance in the suspension otherwise the (cold) tyres loose lateral traction and just skip across the tarmac,
I've always set up my hillclimb cars as with spring rates soft as possible and controlling roll stiffness with higher damping rates and thicker anti roll bars.

eg, the micra runs
32n front springs revalved konis and a 22mm ARB
38n rear spings Saab estate dampers and a 22mm ARB
fair enough the car only weighs 680kg but that's 70% the weight of a well prepped clio road going hillclimber

You make the same point as other experienced drivers. I went for the 80/80 as the surface etc can vary so much.

Fingers crossed I'll be able to update with them fitted very soon.

Tom