19/11/2007 23:00:57 Gary&BVZ Hi all ..Further to my mails a while ago I report that I am well pleased with my Toyo Proxes T1 - R tyres ... Wearing very well .. Many of you have passed me and observed their grip ... My new question is will an increase from 205 / 40 to 215 / 45 be acceptable on a ZR 160 or will I be rubbing inner or outer wings ????? Or any other parts I am not aware of ... All thoughts appreciated ... Bests ..Gary & BVZ ..:)

20/11/2007 12:37:03 Stu Hi Gary It's a difficult call, as you know we don't have too many ZR's come out and play with us([I]which hopefully will improve in 2008.[/I]) so there won't be many here who can answer your query. It might be worth asking on one of the other more model specific forums, maybe xpower or mgrover.org I'll be surprised if someone hasn't tried it Stu;)

20/11/2007 13:43:14 Steve Hill Here is the home of the ZR fraternity, you may need to register to access the forum. It's an interesting place. :) [URL="http://www.themgzr.co.uk/"]http://www.themgzr.co.uk/[/URL]

22/11/2007 18:15:36 Ralph 215 tyres on 7J rims is at the absolute limit. I would recommend getting wider rims (7.5J) if you are going to be using these tyres in earnest on track. This is what I did with my Mk1 ZS180.

23/11/2007 07:46:59 Martin C Hi Gary, The question I would ask is "Why do you want to do it?"

23/11/2007 13:30:59 Gary&BVZ [b]Why ????[/b] Hi Martin ...Thats a good question ...I am thinking along these lines ... Looking for more top speed on straights ....:eek: Need to exit corners faster , so looking for max grip through corner . I have purchased a spare set of used 17" ZR 160 wheels and am thinking of putting Proxes R888 or Yoko A048R on them ... Trouble is neither come in 205/45-17 ....Hence my question about fitting 215/45 or 205/40 ...:confused: All advice and thoughts welcome ....

28/11/2007 22:00:42 Martin C [quote=Gary&BVZ]Hi Martin ...Thats a good question ...I am thinking along these lines ... Looking for more top speed on straights ....:eek: Need to exit corners faster , so looking for max grip through corner . I have purchased a spare set of used 17" ZR 160 wheels and am thinking of putting Proxes R888 or Yoko A048R on them ... Trouble is neither come in 205/45-17 ....Hence my question about fitting 215/45 or 205/40 ...:confused: All advice and thoughts welcome ....[/quote] Hi Gary, Those were the answers I was expecting and too be honest I don't think you'll find a significant difference. Certainly they won't improve your straight line speed, bigger contact area = more rolling resistance, hence why dragsters have bicycle type front wheels. But your reasoning could be made for the corner speeds, bigger contact patch more grip. But the step up is not that great so you might not notice the difference :confused: However it may make a difference in the confidence one has to attack a corner. The belief that bigger tyres will make the car more sure footed and consequently you will be faster. But have you tried experimenting with your tyre pressures :confused: . Of course this does take up valuable track time, especially if the handling becomes worse:eek: . But a couple of p.s.i. adjustment at a time should not make it too drastic and a note book to record conditions, pressures front and rear and the effects it had can be invaluable. Whilst at Goodwood we were fairly evenly matched for speed I thought, with perhaps me carrying a little more through the corners. I have of course 120 to your 160, but no mods to the suspension set up, if the ZR is like the ZS it has phenominal handling. I am at this moment running FULLRUN tyres at 205/45X17. Never heard of them :confused:, no neither have I :p and they handled the situation fine, they are the tyres that came on the wheels. OK I know in the wet they are a very different proposition, I get chronic understeer and adapt my driving style to get speed through the corner. So instead of powering through after an apex, I have to maintain momentum on a feathered throttle and power on when almost straight. Were these tyres the reason for my off at Woodcote :mad: , well not entirely, I came off the brakes too early. Because I was carrying too much speed in I did understeer off, but it was my fault, I overestimated my (brake) lift off point. Would this have happened with better tyres :confused:, probably not, greater margin for error and YES when these tyres are shot I will be buying a proper set of boots :). So I would go with your 215's, I don't think you will get any rubbing issues, but as Ralph pointed out they are at the limit for 7j's. But having bought the wheels now you're not going to go and buy bigger ones.... are you:confused: But remember there is always the plain and simple fact no matter what one does there are always going to be quicker cars or drivers out there and at some point one reaches ones own and the cars limit. But it is fun getting there, just as long as it doesn't end in tears. Cheers, Martin

10/12/2007 17:15:41 rozzr [b]re topic[/b] Hi there, not sure if this is any use, but just to let you know i was running 215/40 tyres with 17" wheels on my ZR lowered 35mm all round. Rory

15/12/2009 12:52:09 prb Gary, Just picked up this thread as I am heading towards replacing the road rubber on the ZR. Which way did you go? Having re-read your original question, it occurred that the higher aspect ratio would defeat your objective of better speed out of a corner as the gearing would effectively be higher, reducing acceleration. I am interested in how it all went. Rgds, Paul

16/12/2009 21:10:01 Gary&BVZ Hi Paul ..I will send you a PM .. Regards ..Gary ..

17/12/2009 17:41:17 Ralph [quote=prb]Gary, Just picked up this thread as I am heading towards replacing the road rubber on the ZR. Which way did you go? Having re-read your original question, it occurred that the higher aspect ratio would defeat your objective of better speed out of a corner as the gearing would effectively be higher, reducing acceleration. I am interested in how it all went. Rgds, Paul[/quote] The higher aspect ratio is negated by the increase in width - 205/40r17 vs 215/45r17 have very similar rolling circumference.