Is the rx8 a 10/10ths car?

[Django91]

Question to the more experienced rx8 owners among us,

Would you describe the rx8 as a comfortable drivers car at and beyond 10/10ths?
Have you made certain modifications on your car that have made its behaviour on the track more predictable at and beyond it limits.

Toby

[warpc0il]

http://www.1010film.com an interesting film for petrolheads

[79398]

Comfortable driving car, just, just put a Petit racing short shift on, and the difference is emmence, I have Tein street coilovers on my PZ and am more than happy with everything they do.

[ChrisHolmes]

RR54 is comfortable on track but not so on public roads due to noise and harsh suspension.
YA56 is more comfortable now it has an original standard exhaust and once I replace the PZ suspension with OE standard units it will be a more comfortable ride.
Up to 10/10ths I find the RX-8 is predictable and hence comfortable however past 10/10ths like any car it’s not a comfortable place to be unless one is skilled enough to go “catch” it of course.

[Delanor]

I can`t really remember the others as it was too many years ago but actually in terms of the 40th Anniversary car for the last 12 years I would say 11/10ths.

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Del.

[qwakers]

the rx8 is the most predictable car at the limit ive ever driven. i reckon you could start a slide and have time to read the manual too see what you need to do to catch it.
now my previous car, a sw20 mr2 rev1 with a 3vz-fe swapped into it, not so much lol. that thing was nasty on the limit!

[350matt]

agreed its a very friendly chassis, so yes its a 10/10ths car without a doubt, which is quite unusual in rwd

[Django91]

Would anyone be able to suggest tyres that have relatively low grip but predictable behaviour, wondering if anyone has tried this before, might be a good way to enjoy the natural balance of the car at relatively lower speeds, toyota gt86 style.

[Conan]

It’s difficult to get a rubbish tyre that gives up its grip progressively
A rubbish tyre tends to be rubbish in all areas
I would suggest a good tyre with very little tread for the purpose you require .
Remember you will only be able to explore the limits on track.
Regards
Pete

[Django91]

Toyota choose to under-specify the tyres on the GT86 as it was the only way that they could achieve the fuel consumption and emissions requirements, as the narrow tyres have a lower rolling resistance.

Specifically they choose the same tyres as the Prius, which needed them for range.

These tyres aren't "low grip" as such, they're just narrower than you'd normally specify for a sports car of that weight and power.

These means that you can break traction easier, if you try hard enough, but they still work as quality tyres under normal conditions.

You could try fitting narrower tyres to an RX-8 to get the same effect but it could be a very interesting discussion with your insurance company...

[Nerdstrike]

These means that you can break traction easier, if you try hard enough, but they still work as quality tyres under normal conditions.

It's not very hard at all although the default setup makes it understeer if you thump power on a stable faster corner. Hilarity ensues at 3 degrees on a damp morning! The Primacy HP is a ditch-finder of a tyre in the wet - it reminds me of the Bridgestone RE040 but with less dry grip. It can be tricky to pull away on embarrassingly shallow inclines when the road is a bit greasy.

In my opinion based on how the car moves, what makes the '86 arse-happy in comparison to the RX8 is:
1) More roll in the rear suspension than the front so it loads up one tyre more
2) Not a lot of contact patch from 215/45R17
3) Shorter wheel base (I think)
4) Better torque than a standard Renesis can deliver at lower RPM.
5) Weight balance forward of neutral

You could achieve some of these things by lightening the rear, changing toe-in/out (just a little bit), not adding more tyre, stiffening the front ARB but not the rear. Don't fit the Primacy!

[Ranjan]

Very predictable and controllable at the limit, so much so that it is a very popular car to teach folks track skills.
Just buy some worn premium tyres off eBay and go have some fun on track; remember switch that damned DSC fully off.

Ranjan.

[Django91]

Thanks everyone for such informative and interesting replies. I will raise you one more and ask another one thats been on my mind,

How much would a car have to be lowered that you start seeing issues related to a lower roll center. and increased body roll from this. Does a lower profile tyre count toward this issue.

[Conan]

Hi Django,
The RX-8 is not a 10/10ths car HOWEVER THE RX-8 PZ IS A 12/10ths car
In answer to a few of your questions I’ve posted up an old link to a suspension group buy which may or may not be informative if you have some time to spare
I’ve also posted what is essentially a standard RX-8 231 on track at Silverstone National circuit among cars of 300 - 400 plus HP
Which gives you some idea of what the car is capable of.
The weather was around 0 - 2 degrees with ice in the paddock, slightly damp track.
Car was on 40,000 ml PZ suspension and semi slicks, it was the passengers first ever experience on track.
PZ SUSPENSION (brand new) GROUP BUY !! POST UP WHEN RECEIVED



With regards to lowering a car on the suspension :
This doesn’t always have the desired effect or improve things and it’s also important to have enough hight in the sidewall to allow some flex and give regarding low profile tyres.
It’s probably more important to keep the wishbones etc fairly level for 99% of people
235 x 40 x 18 tyres are an improvement and lower the car 7mm
17” wheels can lower the car further
The PZ suspension also lowers the car further
Regards
Pete

[ChrisHolmes]

Nice demonstration there Pete, though I suspect is says as much about the nut holding the steering wheel, as it does about the suspension

[ChrisHolmes]

I remember that video well when you dived up my left side under braking into Brookands at 10:13 and nearly rammed the Honda. Good fast driving but not really a good example of how to drive on a track day.

[Conan]

I remember that video well when you dived up my left side under braking into Brookands at 10:13 and nearly rammed the Honda. Good fast driving but not really a good example of how to drive on a track day.

It’s not an example of how to drive on a track day and never has been as most would realise.
It’s an example of a virtually standard RX-8 on PZ suspension
There was never any danger of raming another car as the passenger can confirm rather than your opinion.
Overtaking on both sides was allowed on that occasion and the car is never anywhere near the limit that people may assume which the passenger can also attest to.

[Ranjan]

Pete, you and your PZ fixation

Nice bit of driving, have not seen that video before.

Ranjan.

[warpc0il]

Played at 1.5x it looks like something out of a video game

[350matt]

Blimey I was there that day, in the Cosworth Gt86, where you go flying by early on

I had a near miss with someone on that same outing




and here's the full session



looking at the footage now I was being rather cautious

[Django91]

Hi guys thanks for the replies,

So my car has parts that have been recommended by many here:
1)Eibach springs
2)Racing Beat roll bars
3)235/40r18 tyres
4)Fast road alignment

I have spoken about some characteristics of my car that were bothering me before in earlier posts, such as marginal ride quality which I think is down to my tyre choice and those have very stiff side wall( eagle f1 super-sport) and super sharp(nervy) front end, which could be alignment related.

I have been doing some reading around on roll centers and springs, and based on my newfound 'vocabulary', I can describe my car as having lesser body roll, but when you put on some steering lock it seems to roll more 'quickly' before it settles into a flatter stance and that just makes the car feel a bit nervy. The eibach springs are progressive, could it just be that the first few degrees of lean are in the 'soft' region of the spring? Maybe the 'faster' roll has something to do with the change in roll center. I think overall the spring and tyre profile lowers the car around 15mm?

I have been doing my recent driving in a completely standard rx8, and that car has a lot of body roll but everything just seems to happen in a more calm and slower paced manner.

Trying to diagnose handling characteristics based on textbook knowledge is a bit like trying to diagnose illness based on google symptoms, so I'm prolly plain wrong about some of those things.

Toby

[350matt]

I'd say the racing beat roll bars are probably the biggest contributor to the feel in the handling that you don't like

do you have the stock roll bars that you can put back on but keep everything else the same?
also what tyre pressures are you using? and what is the sidewall rating of the tyre?

[Django91]

Hi Matt,

Why do you think its the roll bars? It feels nice once the car has settle into a 'stance' but seems to roll more quickly. Stock car has way too much body roll, on my car i put the springs on first and it didn't make a big difference. Did it through a specialist who suggested roll bars over coilovers to keep the ride quality close to OEM.
I don't have the stock roll bars unfortunately, tyre pressure between 30-32 psi I think haven't checked in a while but seems 'ok'. Its this tyre basically:

https://www.camskill.co.uk/m61b0s322p16 ... se%3A_72dB

[warpc0il]

I discovered that "sudden roll, then stance" on a friends Capri many years ago.

After a bit of poking about we discovered that the ARB mounting rubbers were very loose around the bars.
Not sure of they'd worn or shrunk or if the wrong rubbers had been fitted.
Anyway, the ARB's weren't doing anything until the slack was taken up by one side pushing against the other, which perfectly explained the strange handling - which he hadn't noticed and just assumed was normal for a 2.8i.

Replacing the mounting rubbers transformed the handling and cured an occasional "clunk" that I hadn't heard but his wife use to complain about.

[Django91]

I discovered that "sudden roll, then stance" on a friends Capri many years ago.

After a bit of poking about we discovered that the ARB mounting rubbers were very loose around the bars.
Not sure of they'd worn or shrunk or if the wrong rubbers had been fitted.
Anyway, the ARB's weren't doing anything until the slack was taken up by one side pushing against the other, which perfectly explained the strange handling - which he hadn't noticed and just assumed was normal for a 2.8i.

Replacing the mounting rubbers transformed the handling and cured an occasional "clunk" that I hadn't heard but his wife use to complain about.

This is interesting, might be whats going on with mine. Its sat up for some engine work at the mo, might suggest for this to be checked, I bought them 2nd hand from the specialist, will ask him to have a look. Think I forgot to mention earlier I am running the roll bars with OEM drop links.

First time I had them installed there was definitely a clunking noise turning left, and then it vanished. When I had the car serviced a few thousand miles later, one of the drop links had come loose apparently, was re-connected and the clunking noise was back again, which then vanished again.
Wondering if there's something going on there. Is the noise going away when it comes loose again maybe?