Which 205/50/15 semi slicks?

[davekmoore]

Kudos to Trackphotos for the pics of the wheels and tyres in the car and for the comments about whether it's worth bothering swapping road and track tyres.

Based on this and other helpful comments (thanks everyone) I'm tending to go with the set of Konig 15x8 +25 wheels already ordered and to add R888s. With BARMY's coilovers and enough negative camber and braided brake lines I can fit either 205/50s or 225/45s. Judging from Trackphoto's pics and my own measurements, going with my preferred 225/45s would rule out ever carrying them in the car. This means I need to make the right choice of dual purpose tyre, albeit with the compromises that have been well stated here about being sensible in the wet and cold.

So, looking for final (?) opinions please on why I would not go for R888 225/45/15s and just leave them on the car all the time.

[deviant]

Buy them. You will be happy with them.

[chrons_rotary]

Not sure you will need the extra width tyre, unless you are super competitive, then the 205/50 would be fine (and cheaper i think).
I've got a 180rwkw NA8 turbo, and 2 year old half worn 205/50 R888s and they still manage to hold down the power pretty well.

Up to you whether you think you'll need the extra grip, with the possible issues with guard rolling, etc.

[ausbuoy]

Thanks for the great pics. Is there anything a little more, erm, stealthy at all?

Hey Dave-Probly this post is about D to D but I need a Guinea pig to test the newfound talent of pic posting from benevolence of 'Slug Dub:)
so the reality to test the many theories=









Not sure if the photo sequence is A about F but the correct sequence is from the one with the softop up which is on arrival at Wakefield Park after drive from Melbourne (not your 'normal' drive to the track commute, but to prove a point, "overkill is appropriate"!:)

so you see three 'track whls/tyres in the pax posit + inverted seat & other hidden necessities, and 4th track wheel in the boot. Not as traditional with the magic bungee cord fastener but not illegal, and plenty fresh air dilutes the attendant CO fumes. The reason no closey is these are 9" 6ULs with 225 45 15 tyres so it CAN be done & no attention from the vigilantes.

Then you see them unloaded/trackies on/go have heart failure for cpl hours or so/reload for the next trip( to Newcastle)/ & Bob's you uncle!:)

(BTW you may recognise the road wheels as they used to be under your 'Barmy' once up.....

Greg.

[davekmoore]

That, Greg, is a quality post.

R888s ordered today in 205/50/15.

[ausbuoy]

BTW Dave, the 'Turbonator' now has 15 X 7 ALT roadies (your Racing harts went to a better place=Helen in N'castle had an urgent need), and they are shod with 205 50 15 R888s. They had enuf grip to hook up and tear a cpl of teeh off 2nd cog with the 'T''s newfound muscle:(see N D's F/Book page for explicit image!:)
As you know from Broadford, 'J' has AO50s on his SE that are 225 55 15 and you can attest to their capability in the wet/dry from that day.
My point is, no matter what tyre you choose, it will be at some time the RIGHTEST or the WRONGEST depending on the conditions, and what you are trying to do with it, and there are as many 'correct' opinions as there are people to ask, so just as with blondes/brunettes/redheads, try to pick what will work for you 'mostly' for most of your needs, OR, re/mortgage and buy 3or 4 sets of wheel/tyre combos that will allow you a smug smile whenever this insoluble dilemma arises!:)

[davekmoore]

Blondes, final choice, locked in, permanently, no compromise. Last Sunday she'd put up with 10 years of marriage with me.

Even got a blond dog, although he's actually supposed to be Golden.

The tyres and wheels will be a compromise as there will be one set. I'll still not be the quickest on the track or the most comfortable on the road but then I also don't plan to have a Bentley dedicated road car and a modified Ferrari track car.

[Charlie Brown]

Dave,
Magna Blue has given very sound advice. Stay away from true R-Spec for a road tyre as they need heat to grip as well as "normal" road tyres. No heat = spin in the first corner. They also don't perform in the wet.

Just a comment on R-Spec's.
I've just swapped to A050's, had my first run with them last weekend at Eastern Creek GP. They are very expensive at almost $1900 for 225x45x16 with heat treatment.

I know it's not a fair comparison as Turn 6 had been changed since I ran there last time with V70A's on board 2 years ago but the A050's were 3 seconds a lap quicker. They had far more grip through corners I previously struggled with getting around. They did go off after four laps, as most tyres will, if you over drive them. Keep them in the right temperature range and they are fantastic.

For my thinking R888's have been around for a long time and just don't measure up to new technology tyres. Around Wakefield the V70A would be a second and a half quicker than R888. The A050's look to be over a second quicker than the V70A.

My suggestion. Keep a set of wheels for general road use and bolt on R-Specs to drive to the track.

[Regie]

Watch out Ralph aye Phill??

[Dan]

Wow, that's an expensive set of tyres, but it sounds like it was worth it

I'm tossing up getting a set myself before the next Supersprints round.

[davekmoore]

Playing Devil's Advocate here now:

If I left R888s on the car all the time, would they be heat cycled out after a month of daily driving and a couple of sprints, or do only high temp/stress events* such as the sprints contribute to heat cycling?

* Not that tyres get especially stressed when I'm driving, of course. It's the brakes I kill.

[Dan]

You won't heat cycle them driving on the road.

The tyre pressure you'll run on the road will minimise sidewall flex and control heat even during spirited driving.

You might wear them out over an extended period of driving as they are softer than street tyres but that's just par for the course. Saying that 888's are pretty durable.

If you plan on daily driving your MX5 just buy another set of wheels and street tyres. These tyres are going to be illegal on the street long before they are too snagged to drive on the track. Which means you are up a creek if you have an accident on the road or you will be spending a fortune to replace tyres all the time.

[manga_blue]

For my thinking R888's have been around for a long time and just don't measure up to new technology tyres. Around Wakefield the V70A would be a second and a half quicker than R888. The A050's look to be over a second quicker than the V70A.

That would be true for a NSW driver. Vic drivers have always preferred R888/NT01. NSW drivers have mostly used V70A as their bread and butter tyre. For once the reason is not inter-state prejudice.

R888s do best when you heat them up slowly. This suits the longer session times down there. I've found they give their best at around laps 5/6 and then again around 8/9, long after NSW drivers are back in the pits. V70A is better for the mad NSW 4 lap dashes.

Nowadays though the A050s are streets ahead of both of them.

Having said all that I can't understand why anyone would voluntarily inflict any of these tyres on themselves as daily drivers.

[davekmoore]

Thanks Dan

It's sort of an 80% DD and there is now a second set of road wheels and tyres.

The 888s will now only be used to drive to the track and at the track so from what you say that should all work out save for having to get spacers so the road wheels will clear the brakes.

[davekmoore]

So run what pressures for 888s on the way to the track?