Tyre Pressures

[ChrisHolmes]

Have you had a “full” suspension alignment check?

[Django91]

Have you had a “full” suspension alignment check?

Its had a full geometry change to fast road setup with corner weighting etc.

[ChrisHolmes]

That could be why your car feels “skittish” compared to a standard car.

[350matt]

do you know what the actual settings are that are on the car?

[Django91]

do you know what the actual settings are that are on the car?

Yes, will try get a photo of the setup sheet

[casey]

For comparison, I've run with this setup and find it works well on track (and road) with my car and mods (see sig below).

Alignment Jan 2013.jpg

[Django91]

For comparison, I've run with this setup and find it works well on track (and road) with my car and mods (see sig below).

Alignment Jan 2013.jpg

Cant seem to find my alignment sheet but if my memory serves me right camber numbers look similar. Unsure about toe and castor though.

[Django91]

Anyone else on here who has experience with the Goodyear f1 supersport in the standard size?

[auditt235]

That's also typical of a "fast-road geometry" which is designed for experienced drivers that want to be able to control the stance of the car with the throttle.

If you're "learning" the car then you'd be better with a more conservative geometry, or just take your time and get a feel for it.

There are two other things that can also cause (what appears to be) excessive oversteer;
- a stiff universal joint on the steering column - see viewtopic.php?f=25&t=47002
- too tight a nut holding the steering wheel...

Seriously, your grip on the wheel should be really light and, other than parking, you should hardly be "gripping" at all.

Only just seen this thread...brought back memories of my first thrash in an RX8 back in 2006. I had just 'run it in' and was travelling down the B4100 coming up to a roundabout outside Aston Martin heading west. I decided to give it some wellie in 2nd as I turned right to break the back end...the first part was ok..but I still had the stabilty toys switched on...as I turned into the slide, the 'toys' decided that I wanted to turn left NOW...nearly shot up the kerb. Fortunately, as it was new I got to do the Prodrive driving course where they showed us how to switch the toys off...much easier to drive after. Loved the low friction test, but couldn't get the hang of the high speed top turn on the circuit...it was all just paint lines - I had no idea where the road went...can't beat dry stone walls to mark out where the road goes.

John

[Django91]

For comparison, I've run with this setup and find it works well on track (and road) with my car and mods (see sig below).

Alignment Jan 2013.jpg

Did it affect the handling/feel of your car when you got those spacers?

[bc-49]

TBH, I didn't notice any significant difference with the spacers. I fitted them mainly for aesthetics, so the tyres filled the wheel arches better.

[Django91]

TBH, I didn't notice any significant difference with the spacers. I fitted them mainly for aesthetics, so the tyres filled the wheel arches better.

Fair enough, yes the arches could use a bit of filling up, just wondering if there were anuly negative effects with them on

[auditt235]

I see that you have got more rear camber than front - I read somewhere.....

Post by auditt235 » Sun Jun 07, 2020 2:47 pm
Hi, have been interested in RX8 suspension settings for some time, and happened to read an article this weekend about the basics of setting up a race car by some F1 mechanic....it said rear camber always less than front unless you want excess oversteer?? Anyway couldn't find the article, but found this one .. http://racetrackdriving.com/car-setup/track-alignment/ I apologise for it being from the US... Some interesting thoughts about RWD..

However, I do understand that the adjustment on the back does allow for more camber??

[warpc0il]

A lot of that depends on the dynamics of both the front and rear suspension.

Many, like the Escort Mexico, significantly change the camber as the suspension is loaded/unloaded, so the relationship between front and rear camber has to take that into account.

There is no "one size fits all" for rwd cars.

Sent from my SM-G800F using Tapatalk

[ChrisHolmes]

A lot of that depends on the dynamics of both the front and rear suspension.

Many, like the Escort Mexico, significantly change the camber as the suspension is loaded/unloaded, so the relationship between front and rear camber has to take that into account.

There is no "one size fits all" for rwd cars.

Sent from my SM-G800F using Tapatalk

Live axles, Watts links, wishbones, A arms etc: Will all require different toe and camber settings and all are RWD designs

[auditt235]

No I agree with all that. I was lucky in my day with my RS2000 (ex-Gill Robinson works car - if only I had kept it...). Live axle and meaning more neg camber at the front end and a very 'throwable' car it was.

[Conan]

TBH, I didn't notice any significant difference with the spacers. I fitted them mainly for aesthetics, so the tyres filled the wheel arches better.

Fair enough, yes the arches could use a bit of filling up, just wondering if there were anuly negative effects with them on

Don’t forget that Casey can adjust his bump and rebound to compensate for the extra leverage created by spacers
Pete

[Conan]

I see that you have got more rear camber than front - I read somewhere.....

Post by auditt235 » Sun Jun 07, 2020 2:47 pm
Hi, have been interested in RX8 suspension settings for some time, and happened to read an article this weekend about the basics of setting up a race car by some F1 mechanic....it said rear camber always less than front unless you want excess oversteer?? Anyway couldn't find the article, but found this one .. http://racetrackdriving.com/car-setup/track-alignment/ I apologise for it being from the US... Some interesting thoughts about RWD..

However, I do understand that the adjustment on the back does allow for more camber??

I haven’t read the thread
An F1 mechanic tends to work on single seaters
I always ran more camber on the rear on my single seater and won 7 championships, I was helped by a race engineer who helped to get a driver into F1
Saloon car set up is different to single seater set up
The main things to look at are roll bars, width of tyre, spring rates, speed driver corners at etc, etc
A slower driver in corners will require less camber than a faster one ( assuming they had identical cars )
Pete

[PJ_Parsons]

I don’t have a clue about suspension setup but can offer you experience of the tyre you are using. I use the Eagle F1 Supersports myself (same size), car is an S1 with PZ suspension, standard geometry. They are a great tyre if, and that is a big if, you do trackdays. They work amazingly well on track, wet or dry, which is quite something. They are very close to semi-slicks in performance. On the road, they are also great with good wet and dry grip. I’ve not noticed any obvious handling vices on the road, but I leave the hard cornering for the track. The tyre sidewalls are very stiff compared to normal high performance road tyres. This makes them edgier, but more nimble on track. The ride is quite firm and might make the car feel less planted than it is. If I wasn’t tracking the car, I would use the Eagle F1 Assymetric 5’s. I have these on a Swift Sport and the ride is smooth, very compliant and they do not want for grip. The Vredestein Ultrac Vorti is another good road tyre that is smooth and grippy.

Why not do a track day on the Supersports? Get a feel for what they are all about on the limit and you may well enjoy them more on the road. They are an amazing tyre, just not your regular high performance road tyre.

[Conan]

Have you had a “full” suspension alignment check?

Its had a full geometry change to fast road setup with corner weighting etc.

Hi Toby,
I jotted an answer on a piece of paper a couple of months ago in France then lost the paper and the thread, found it today so may as well post it.
Your car cannot have been corner weighted as you don’t have hight adjustable dampers.
You really need to obtain the set up sheet so we can see it to help. ( who did it as it should be on their system to obtain a copy)
I really don’t think this is your tyres from what you describe and I’ve never known a tyre that didn’t squeal ( not recommend on the road ) 235 x 40 x 18 is the best tyre for the car, I recommended this back in 2011 ish along with the Vreds you had which were a very controllable and forgiving tyre that could be used all year.
I tried 5 different sets of tyres in quick succession to appraise those.
Your problem sounds like front drop links : ( it’s not always obviously broken ) check or change all drop links and check roll bars
I took an RX-8 flat through the cranes curves at Donington once with a broken front drop link which made it interesting.

Casey”s camber looks like it may be measured in degrees and minutes and is very aggressive.
For example : left rear -2.33 degrees = -2 degrees 19 minutes
If your set up is anywhere near this it’s way too much for your application.
Casey is a very competent driver with 60 + track days and a million miles

You should try, all in degrees :
Fast road : camber front 1.0 rear 1.25
Track : camber front 1.25 rear 1.5
Front toe : tiniest bit toe in for road and track
Regards
Pete

[Django91]

Have you had a “full” suspension alignment check?

Its had a full geometry change to fast road setup with corner weighting etc.

Hi Toby,
I jotted an answer on a piece of paper a couple of months ago in France then lost the paper and the thread, found it today so may as well post it.
Your car cannot have been corner weighted as you don’t have hight adjustable dampers.
You really need to obtain the set up sheet so we can see it to help. ( who did it as it should be on their system to obtain a copy)
I really don’t think this is your tyres from what you describe and I’ve never known a tyre that didn’t squeal ( not recommend on the road ) 235 x 40 x 18 is the best tyre for the car, I recommended this back in 2011 ish along with the Vreds you had which were a very controllable and forgiving tyre that could be used all year.
I tried 5 different sets of tyres in quick succession to appraise those.
Your problem sounds like front drop links : ( it’s not always obviously broken ) check or change all drop links and check roll bars
I took an RX-8 flat through the cranes curves at Donington once with a broken front drop link which made it interesting.

Casey”s camber looks like it may be measured in degrees and minutes and is very aggressive.
For example : left rear -2.33 degrees = -2 degrees 19 minutes
If your set up is anywhere near this it’s way too much for your application.
Casey is a very competent driver with 60 + track days and a million miles

You should try, all in degrees :
Fast road : camber front 1.0 rear 1.25
Track : camber front 1.25 rear 1.5
Front toe : tiniest bit toe in for road and track
Regards
Pete

It's strange I've had the chance to try 3 rx8's. First one had different brands and sizes front to rear, 2nd one had Vredestein Ultracs which were way past their usage date and were terrible, this set was swapped for goodyear f1 supersport, 3rd one has goodyear f1 assymmetric 5.

Can't remember back to the 1st car, but 2nd and 3rd cars on either of the goodyears, definitely no high pitched tyre squeal whilst over/understeering just a sorta scrubbing noise. Don't know why. Alignment was done by harveys autotech based closed to castle combe, they have since changed their system and don't have the records back to mine

[PaulAV]

I found after having my geometry set up to standard by a wheel refurbishment company the traction control kicked in on the rear whilst turn in seemed very aggressive, I put it down to be tyres at the time, I had the geometry reset by a decent the fitting company and the rear end began behaving correctly and the front end was less aggressive. Not all geometry set up is equal(this was set to Mazda specifications on both occasions)

[warpc0il]

The Mazda specifications, even if they measure the ride-height and refer to the tables correctly, which most don't, still give quite wide tolerances on some of the key parameters.

If two sides were outside of the range, one above and one below, and they were both adjusted to be with the range, still with one near the top and the other near the bottom, then that's still sufficiently different to create an issue, even though the system would produce a printout "all in the green".

[PaulAV]

I always try to watch what is happening and get a printout to see what's been altered and what they have achieved