kartaphilos

I thought this data would be interesting for all of you that wonder about how tyres compare for hard driving. I've been competing for almost all of this year on Toyo Proxy T1-R's but when the rears were worn I thought I'd try some Bridgestone RE050A (MZ - S2000 specific fitment) at the rear. My first event on the tyres was a sprint at Cadwell Park (my first time at the circuit - what a great place!). I had a reasonably good result there, beating a Porsche GT3 RS that I'm usually a couple of seconds behind and within 3 secs of an EVO IX that I'm usually 5 secs adrift.

Today I sprinted at Lydden circuit in Kent and where I've sprinted 3 times previously. My previous best time on Toyo's was 88.48secs for 1.75 laps from a standing start. Today I beat that time by over 2.5secs with an 85.93.

This plot from the datalogger shows some important detail on the differences. The red lines on the graphs are today's time and the black line is my previous best.


The graph in the top right of the pic is the corner radius of each corner which effectively shows if my lines are any good. In this case the red line and black lines mostly overlay, sometimes the red is better, sometimes the black is better. Thsi means that I was drving the lines pretty much the same. The graph in the lower left shows an estimate of engine power (BTW: about 245 at crank if you're curious) and shows that power is the same as the previous run. Track conditions today were dry but cold but my previous best was in May which was also dry but warmer (not as warm as it should have been in may though!!). So what this data shows is that the conditions and driving on the day were near enough the same (although I reckon I did find a better line through devil's elbow and better braking for paddock).

The graph on the bottom right show's a trace of speed for each run and you can clearly see I am getting better speed through almost all corners. This I put down to better lateral grip from the RE050's. I've never got mid corner understeer on the car before but I am getting that now in a few corners. Overall I have much more grip from the rear.

Here's my verdict...
- The RE050's don't have as good drive of the line, they spin up easier. The Toyo's are better here.
- the 50's also take a few corners to come up to good grip. The Toyo's had good grip from cold.
- The 50's have much better grip in the first half of the corner and you can really lean on them in the middle of the corner.
- Under power the '50's and the T1-R's have similar grip, they both have the same level of desire for producing power slides. The Toyo is more forgiving for lower speed corners the '50's more stable for higher speed corners.
- In the wet both seemed good but the '50's needed more warming up and I'll wait and see what they're like when the tread depth wears down.

So what would I buy? Either really. For higher speed sprints/hillclimbs and track work defintiely the '50's. For the road at built up area speeds (<50) and motorways the Toyo's (especially if the roads are wet).

Cheers,
Matt

motogp1

Great write up matt.

MB

Oooh the "Toyo are shit" brigade won't like that

Great info.

I've been a Toyo advocate since about 2002 - I do think they need to bring out something more up to date though. I wouldn't have much else on an S2000.

Very cool data logging thing you have there too!

Stradale

I think RE050A are different than RE050 that wears the S from the begging.Am I right?

Dembo

Why? He's proved Toyos are shit.

Good write up, but you should really get the RE050s on the front as well and try that.

Si2k

Wait there, you are comparing on different days.

Today was very cold.

Ultra_Nexus

As good as the write up is, the data is inconclusive as Si is pointing at.

I refuse to believe that some corner could be taken over 10mph faster.

kartaphilos

I also trust my bum data logger and it concurs with the results. Comparing times with other competitors in the same sprint the conditions were within 0.5-1 secs. My driving may have accounted for another .5 secs. Extra rear grip accounted for the rest.

MARTS2K

I have T1-R's on the back and I must admit the grip going to work this morning on heavy surface water was fantastic with the SO2's the back would twitch feel really frightening ...these are brilliant and I hit roundabouts in the wet at speed and it just sticks whereas before id be trying to hold the back end by counter steering.

I dont like the soft side wall the T1-R's have the flex is terrible in the dry the SO2's were much better here and back end was very firm and sure due to hard side wall

Even running the T1-R at 36psi its quite flexi!! Im going to try RE050 next purely for the harder side wall

Dembo

Tyres could easily make that sort of difference. And if you're saying it's all down to the cooler temperatures, why has he leap frogged a Porch and gained a couple of seconds on an EVO all on the same day?

With the wibbly wobbly Toyos on the front you must still be suffering on the turn in. I'd bet with RE050s on the front as well you'd gain more time from being able to brake later and turn in sharper.

SO2s were okay in the wet if you could get them warm, but I have to admit driving with the RE050MZs in the wet is certainly more relaxing. Can't speak for the 16" version, but the 17" are very good tyres wet and dry.

But some people are just determined to be different.