Atom 3.5r Geometry and Alignment Setups

[woodsypedia]

Hey Folks

I watched the Harry Metcalf video about his advanced geo setup on his Project 8 Jag. There are a few companies that offer an advanced alignment and some tweaks to make cars incredible on track.

Question: Has anyone done anything similar to their Atom? I've not touched anything geo or suspension wise on the car other than adjusting the firmness on track days. I push my card quite hard on track and I think I'm starting to get to the limits so wondering what else I can do to get a few extra percentage points from it.

Cheers

Chris.

[Curves Junkie]

I watched the Harry Metcalf video about his advanced geo setup on his Project 8 Jag

Link to the video please

[GraemeW]

I’ve been thinking the same after changing the geo on my Alpine A110. The settings of which were designed by David Pook, also in that video.

I was surprised how much better the car was than the already good original settings. David an ex Jaguar chassis engineer now specialises in Alpine settings and aftermarket. Reading about his work, I didn’t realise how much of a difference minor tweaking of the geo makes for different driving styles. Got me thinking about the atom. Ariel will understand all this suff as well, and could perhaps advise on bespoke geo?

[GraemeW]

[Curves Junkie]

Question: Has anyone done anything similar to their Atom?

Yes.
A good idea will be only one parameter change it until it fits, then change the next one.

And don't forget the Corner weight.

I was surprised how much better the car was than the already good original settings.
...
Ariel will understand all this suff as well, and could perhaps advise on bespoke geo?

Perfect video, super explained.
The statement about the ride height is true - but only to a limited extent with the Ariel.
If you adjust the ride height with the spring screw, the explanation is correct.
But if you turn the pushrod, the full capability of the suspension is maintained.

I played around with the setting countless times until I found the right settings for me and thus gained confidence in the car.
And Graeme, you saw in the Alps on our tours together, how much faster I could go in the corners.

The factory can only do a basic set-up. Every rider has to set up the Ariel for his own needs.
For example, some love toe-out, others prefer toe-in. Some prefer understeer, others oversteer, or neither.

[plip1953]

What are the factory recommended settings on the 3.5? What's recommended on the 4 is actually pretty much spot on. But don't just assume that what's on your car right now will be as per factory specs. On some cars the alignment will go out of spec even after one track day. We have ours checked, and adjusted if necessary, before every outing.

[Curves Junkie]

What are the factory recommended settings on the 3.5?

I don't know. Please give Steve from the factory a call.

On some cars the alignment will go out of spec even after one track day. We have ours checked, and adjusted if necessary, before every outing.

Correct. I check my settings myself several times during the season. A three quarter hour job.

[plip1953]

I only work with 4s, but was quite interested to know if there's much if any difference in the factory recommended settings for 3.5 and 4.

On the 4 we've not settled on -1mm total toe out on the front, +4mm total toe in on the rear, -2deg front camber and -2.5deg rear camber.

Would anyone else care to share what they've found works well? Previous experience suggests that few will openly share and most don't have a clue anyway!

[Curves Junkie]

Would anyone else care to share what they've found works well? Previous experience suggests that few will openly share

Yes, unfortunately I have to agree with you there.
I also think it's a pity that, especially in such a small fan community, experiences are not shared. This would certainly help to prevent a lot of accidents.
I have no problem passing on my expertise.


4s?? Is this the American model of the Ariel Atom 4?

Unfortunately I can't tell you much about the AA4, as I drive an AA3.
The chassis values could be similar, but you have to consider that the AA4 is heavier and therefore has more grip on the front axle.

Ride height:
Here viewtopic.php?f=47&t=17315 Henry wrote something about the ride height of the AA3.x.
In my opinion, it is important that the nuts on the coil springs are both set the same - i.e. on each axle. It should also be noted that the more the suspension spring is screwed in, the less the suspension can work. So it is better to set the correct ride height on the pushrod.

Camber and toe:
I drive my AA3 on the mountain passes and track.
Therefore I have set -1.5 to -2.0° camber at the front and -2.0 to -3.25° camber at the rear.
With toe-out, I personally find the vehicle too unsteady on country roads, so I drive 0 to 0.5mm toe-in each side at the front. In the rear I also use 4mm toe-in each side.

Please do not forget: corner weight the car.

[plip1953]

Would anyone else care to share what they've found works well? Previous experience suggests that few will openly share

Yes, unfortunately I have to agree with you there.
I also think it's a pity that, especially in such a small fan community, experiences are not shared. This would certainly help to prevent a lot of accidents.
I have no problem passing on my expertise.


4s?? Is this the American model of the Ariel Atom 4?

Unfortunately I can't tell you much about the AA4, as I drive an AA3.
The chassis values could be similar, but you have to consider that the AA4 is heavier and therefore has more grip on the front axle.

Ride height:
Here viewtopic.php?f=47&t=17315 Henry wrote something about the ride height of the AA3.x.
In my opinion, it is important that the nuts on the coil springs are both set the same - i.e. on each axle. It should also be noted that the more the suspension spring is screwed in, the less the suspension can work. So it is better to set the correct ride height on the pushrod.

Camber and toe:
I drive my AA3 on the mountain passes and track.
Therefore I have set -1.5 to -2.0° camber at the front and -2.0 to -3.25° camber at the rear.
With toe-out, I personally find the vehicle too unsteady on country roads, so I drive 0 to 0.5mm toe-in each side at the front. In the rear I also use 4mm toe-in each side.

Please do not forget: corner weight the car.

4s as in more than one AA4 lol

Your range of camber settings are pretty wide. Have you not found a sweet spot?

Front toe-out isn't everyone's cup of tea, but does tend to make the turn in sharper. 4mm toe in each side on the rear is quite a lot, but if that's what needed to tame the rear end then so be it.

[Curves Junkie]

4s as in more than one AA4

Don't understand this joke.

Your range of camber settings are pretty wide.

No, isn't it.
-1.5° front and range -2.0 to 2.5° rear is perfect for me at the alps.
More is for track.
No - 4mm toe-in each is not too much.

[K20A2]

4s as in more than one AA4

Don't understand this joke.

"I only work with 4s"

"4s" ist hier der Plural von (Atom) 4, also mehrere Atom 4.

[Curves Junkie]

@K20A2

Thx for your support / und die Erklärung in deutsch.

[YannickFr]

Hi!
I tried a lot of setup on mine.
Only track use.
I have ariel’s geo but with more camber.
Front: 0.18° toe out , 2,5° camber (max with the same value R/L)
Rear: 0.25° toe in, 2.8° camber (max with the same value R/L).
You can choose more toe in for the rear, to avoid to much oversteer. But oversteer is why atom is so fun for me.
Depend of your shocks too. I now have ohlins and it sonwell balance!

[Jallan]

Hi,

I had my Atom 3 geo setup and corner weighted by String Theory Garage in Stratford upon Avon. Ben (the owner) is a genius and transformed the way my atom handled. I was having issues with mine following the road camber too much, being difficult to correct when cornering and overall felt unstable.

As I had only had the atom for 6 months or so, I asked him to make it a 'beginner to intermediate friendly' setup, so it will be a lot less likely to snap oversteer and be a bit more forgiving when things go wrong, but you could ask for a more race bias setup if you wanted.

I think it cost about £510 a year ago, it I would say it was worth every penny.

Let me know if you want more info as I'm sure I could dig out the geo settings.