981S Boxster: Steering Feel vs Suspension Geometry & Tyres

[carspath]

My 2016 981 Boxster S is currently completely unmodified and pretty much as it left the factory.

I have had it since new and it now has 40,000 miles on the odometer.
It has been running on Goodyear F1 tyres.

Immediately I bought it I sent it back to Porsche Reading because it felt sloppy.and imprecise.
Their initial response after checking the car was that it was absolutely fine and that the suspension geometry settings were within factory tolerances, but when I persisted they let their Senior Gold Technician test the car and he agreed that the car’s reactions were vaguer than ideal and that this could be resolved by using more extreme and more equal suspension settings at all 4 corners.

He did the necessary adjustments and these transformed the car.

It is now 8 years on , and the car runs very well and the tyre wear rate has been fine.

But I recall the Gold Technician saying that the adjustments he had done were as far as he could go within factory permitted parameters, and he almost seemed to suggest that he could make the car even more feelsome if only he was allowed to breach these factory parameters.

I am throughly happy with my 981S , BUT I would like the steering to be more feelsome- it is vey precise but feels a little distant.

Can somewhere like Centre of Gravity improve the steering feel by fettling the suspension geometry , or is the 981’s EPAS the culprit meaning that no further improvement is possible ?

Ditto , Will changing from Goodyear F1s help with the steering feel , and which tyres would you recommend for a 2016 981S

Thank you

[Royal Jelly]

Sample size of one - I’ve definitely found an improved feel with a fast road setup by a decent geometry shop.

It’s the feel reversion that tells me when the geo needs redoing.

My experience has been on P-Zeros and PS4S tires.

[mr pg]

There's an owner on Youtube with a 981GTS who has had his steering recoded per GT4 settings. He tried GT3 first but preferred the GT4. It was done by Porsche indy PIE Performance in Suffolk.

[carspath]

Thank you both - much appreciated.

How did the Pirelli’s compare against the Michelins?

[dans160]

Slightly more feel with the Michelins which also have softer side walls. As a result they offer more comfort but less support in the corners. I'd go with Michelins because they offer more protection for the rims. That being said, I think 981 rims are slightly narrower than 718 rims which don't support the pirellis all that well. They were fine on my 981.

JZM set my car up. It needs doing again. It's well worth doing and I've not experienced excessive tire wear.

[Royal Jelly]

carspath said:

Thank you both - much appreciated.

How did the Pirelli’s compare against the Michelins?

Early days with the Michelins, but certainly superior across the board. Bear in mind my P-Zeros were N0 ones, I understand the N1 was an improvement.

I found the P-Zeros decent in the dry, but a bit of a liability in the wet.

The Michelins feel better in all aspects, but in damp & wet conditions they’re markedly better.

Definitely get a good geo done. It’s the best ‘modification’ I’ve done on a car - especially when road handling is a 981’s key strength.

[maz8062]

Michelin Cup 2’s are good for responsiveness but not recommended for temps at or around 5C or below. For a dry weather tyre that's reasonably comfortable, quiet and grippy, they're as good as it gets in my view.

[Voodoo Blue]

I'm not sure if this helps but we currently have a 981 Cayman running 19" Eagle F1s and a 718 Boxster running 20" Michelin PS4s. In my opinion the later provide much better feel and grip though some of that might be down to the improvements between models. Neither car has had any changes to suspension or steering.

Interestingly I had a previous Boxster that had Pirellis from new and they had less feel through the twisties and a tendency to loose grip when pressing on.

Based on all of this for everyday road use including road trips, my choice will be to stick with the PS4s. Personally I wouldn't bother with the additional expense/compromise of Cups as the opportunity to properly exploit them in everyday use is negligible and I don't have the talent to appreciate the difference between them and the PS4s anyway.

[Ed.Neumann]

carspath said:

My 2016 981 Boxster S is currently completely unmodified and pretty much as it left the factory.

I have had it since new and it now has 40,000 miles on the odometer.
It has been running on Goodyear F1 tyres.

Immediately I bought it I sent it back to Porsche Reading because it felt sloppy.and imprecise.
Their initial response after checking the car was that it was absolutely fine and that the suspension geometry settings were within factory tolerances, but when I persisted they let their Senior Gold Technician test the car and he agreed that the car’s reactions were vaguer than ideal and that this could be resolved by using more extreme and more equal suspension settings at all 4 corners.

He did the necessary adjustments and these transformed the car.

It is now 8 years on , and the car runs very well and the tyre wear rate has been fine.

But I recall the Gold Technician saying that the adjustments he had done were as far as he could go within factory permitted parameters, and he almost seemed to suggest that he could make the car even more feelsome if only he was allowed to breach these factory parameters.

I am throughly happy with my 981S , BUT I would like the steering to be more feelsome- it is vey precise but feels a little distant.

Can somewhere like Centre of Gravity improve the steering feel by fettling the suspension geometry , or is the 981’s EPAS the culprit meaning that no further improvement is possible ?

Ditto , Will changing from Goodyear F1s help with the steering feel , and which tyres would you recommend for a 2016 981S

Thank you

What do you mean by steering feel? What are you looking for?

If you want to feel more information coming through the road then no, changing the tyres will not really add much as you have electric power steering which filters this out a lot.

However, if you want the steering to feel sharper, quicker away from the mid position, more positive turn in, then yes, different tyres will affect the things.


For steering feel, that really sharp, super precise turn in off centre I have found the following the best...


1. Bridgestone S02A - N rated (Really precise, super focused but a bit too firm and noisy. Hard to get now in the UK too. But if you want to experience how much a tyre can change the feel of a car this is the one. I love them.)

2. Continental Sport Contact 7 (Again really nice turn in and steering response is very quick, can't comment much more on wet grip and comfort as was not my car and the roads we were on were nice roads. But felt really impressive.)

3. Bridgestone Super Sport (Nearly as good turn in as above, pretty comfy, amazing in the wet. In fact my favourite all rounder at the moment.)

3. Cup 2's. (Nice, steering feel pretty good again, not great in the wet and when it gets cold, but the grip is insane when they are warm.)

4. Michelin PS4S (Super comfy, excellent in the wet, wears really well, but steering feel is not great at all, almost like it takes a second to respond, and the car loses that nice super precise steering that you expect from a Porsche. My only caveat here is I have not tried the N Rated version and this has a completely different compound and is meant to rid the tyres of a lot of the negatives.)

5. Michelin PS4 (Like the above but even less feel, however, it is more comfy and quieter, and in the wet even better, more like the Bridgestone Super Sport. In many ways I think if going Michelin, may as well chose these.)



However, if you want more steering feel and you dare enter the "Fast Road Geo" set up thread, then geo will make more difference.

If you add a bit more negative camber and only have 0.01 of front toe in, you will get much sharper steering, however, the back end may then start to feel very loose. You will need to add a bit more negative camber and bring the rear toe right in to get that very planted rear end you are looking for. Around 0.20-0.25 toe in on the rear will give you this, which is well out of the Porsche specs for your car.


The guy who did you geo probably couldn't get passed around 0.40 of negative camber using the Porsche top mounts, rather than he wasn't allowed to go further.
Have a look at the top mounts and see if the three bolts are maxed out or if you have a bit more to go.

[carspath]

Thank you for all your replies, which have been carefully noted.

I had pretty much decided on Michelin PS4 tyres until I read Ed.Neumann’s reply which puts the cat amongst the pidgeons.

In reply to Ed, I am looking for:
(1) More chatter through the steering wheel. I was brought up on non assisted steering and still have 4 cars with non assisted steering all of which give me a pretty unadulterated picture of the road surface’s nuances. I miss this with the 981S.
I note that you say that I am not going to get this extra chatter ( some of which might be useless ‘noise’ ) by changing tyres as the 981’s EPAS is to blame

(2) I am also looking for more resistance when turning the steering wheel away from the dead centre position. I hate overslight steering as per the 355 for instance. I want to work the steering wheel as soon as I move it away from the dead centre position.

Ed’s suggestion that the M PS4 tyres might not help with 1 and 2 disappoints me, but you have driven 981s with all these different tyres so that is objective information that you are providing me with - thank you.

Bearing in mind that I don’t like oversteer and do want very good to excellent wet weather capability ( I won’t be using the car on track ) which tyre would you recommend.

I live in Dorset but am prepared to travel to get the geometry set up properly.
Who would you all suggest , and what general settings / objectives should I ask/emphasise to the technician?

I was interested to hear about using the GT4 suspension settings on a 981S wearing 20 inch wheels.
Have any of you done this and if so what was/is your experience?

Edited by carspath on Wednesday 23 April 21:33

[mr pg]

My experience with our 981CS was that PS4S's were a noticeable improvement over Pzero's all round.

[Royal Jelly]

carspath said:

Thank you for all your replies, which have been carefully noted.

I had pretty much decided on Michelin PS4 tyres until I read Ed.Neumann’s reply which puts the cat amongst the pidgeons.

In reply to Ed, I am looking for:
(1) More chatter through the steering wheel. I was brought up on non assisted steering and still have 4 cars with non assisted steering all of which give me a pretty unadulterated picture of the road surface’s nuances. I miss this with the 981S.
I note that you say that I am not going to get this extra chatter ( some of which might be useless ‘noise’ ) by changing tyres as the 981’s EPAS is to blame

(2) I am also looking for more resistance when turning the steering wheel away from the dead centre position. I hate overslight steering as per the 355 for instance. I want to work the steering wheel as soon as I move it away from the dead centre position.

Ed’s suggestion that the M PS4 tyres might not help with 1 and 2 disappoints me, but you have driven 981s with all these different tyres so that is objective information that you are providing me with - thank you.

Bearing in mind that I don’t like oversteer and do want very good to excellent wet weather capability ( I won’t be using the car on track ) which tyre would you recommend.

I live in Dorset but am prepared to travel to get the geometry set up properly.
Who would you all suggest , and what general settings / objectives should I ask/emphasise to the technician?

I was interested to hear about using the GT4 suspension settings on a 981S wearing 20 inch wheels.
Have any of you done this and if so what was/is your experience?

Edited by carspath on Wednesday 23 April 21:33

At this stage, I think you’re beginning to overthink it, to be honest.

The way ahead is going to be some PS4S/Eagle F1s and a fast road geo from a good shop with a Hunter alignment rig.

That will more or less get you to where the car is capable of, with standard parts.

Feel will improve, as will grip & handling. In my case, it was a huge leap in overall control and enjoyment.

I’d take it from there. For road use, I’m sure it’ll be enough..

[Ed.Neumann]

carspath said:

Thank you for all your replies, which have been carefully noted.

I had pretty much decided on Michelin PS4 tyres until I read Ed.Neumann’s reply which puts the cat amongst the pidgeons.

In reply to Ed, I am looking for:
(1) More chatter through the steering wheel. I was brought up on non assisted steering and still have 4 cars with non assisted steering all of which give me a pretty unadulterated picture of the road surface’s nuances. I miss this with the 981S.
I note that you say that I am not going to get this extra chatter ( some of which might be useless ‘noise’ ) by changing tyres as the 981’s EPAS is to blame

(2) I am also looking for more resistance when turning the steering wheel away from the dead centre position. I hate overslight steering as per the 355 for instance. I want to work the steering wheel as soon as I move it away from the dead centre position.

Ed’s suggestion that the M PS4 tyres might not help with 1 and 2 disappoints me, but you have driven 981s with all these different tyres so that is objective information that you are providing me with - thank you.

Bearing in mind that I don’t like oversteer and do want very good to excellent wet weather capability ( I won’t be using the car on track ) which tyre would you recommend.

I live in Dorset but am prepared to travel to get the geometry set up properly.
Who would you all suggest , and what general settings / objectives should I ask/emphasise to the technician?

I was interested to hear about using the GT4 suspension settings on a 981S wearing 20 inch wheels.
Have any of you done this and if so what was/is your experience?

A lot to unpack there.


You want your steering to feel sharper off centre but you don't want loads of oversteer?

I'm the same.


Number one, Michelins will numb the steering feel, end of. Others will too, but you have options now like the Conti Sport Contact 7s and Bridgestone Super Sport tyres that are more precise.


However, the geo will need to be right too.

You say about GT4 geo, however, I don't think that is really where you want your car for the road, not with standard dampers and ride height, it won't work.


You want to try and get as close to 1.0 of negative camber up front, you will probably get to around 0.6-0.7 with stock hardware, this is fine.
You will then want very little toe in, around 0.01.

This will give you a much quicker steering feel off centre, it will lose that light feel they come with as standard and feel much sharper as soon as you turn.
However the back end will now feel a little lose, like it wants to break away.

So you need to get the rear camber to around -1.4, and, this is the important bit, you now need quite a lot of rear toe in to get that back end feeling really planted, the GT4 uses 0.14 from memory, which is why the car feels so balanced, you should get at least 0.14 on yours, even go to maybe 0.18.

This will give you about as good as you will get steering feel, and although you have induced oversteer adjusting the front axle geo, you have then reduced it with the rear axle geo.

With the camber around 0.07 at the front it won't tramline too badly and won't make it feel too firm either.



Put on a tyre that is not wooly feeling and it should sharpen things up nicely.

[DRH986]

About 10 years ago, my son and I owned virtually identical 987.1S Caymans. Both on 18" PS2 N rated tyres, his with standard suspension and mine with PASM. I'd had mine set up to max out front negative camber, zero front toe and standard Porsche settings at the rear, as recommended by several people on forums at that time. My alignment was done by my local OPC, who got the settings bang on the target values with no variation side to side.

But my son's car was so much nicer feeling in terms of turn in and general feel, despite the occasional knock from 90K mile suspension components! We put his on a Hunter rig and found the settings, apart from front toe, were all within the Porsche recommended limits but far from consistent side to side. But the front toe had a tiny bit of toe out (which we had suspected due to a bit of inner edge wear).

At the end of the day, I concluded that it was the small difference in front toe, despite the supposedly better front camber and more consistent settings on my car, that made his car much more fun to hoon around in. So I'd start with alignment before tyres.