½cwt Posted November 21, 2019 Report Share Posted November 21, 2019 4 minutes ago, PaulQ said: You do realise the rear tyres are nearly 70mm greater in diameter then stock.? Stock is 318mm rolling radius and these are about 352mm so just over 10% oversize which will cause the speedo to under read (17s will be back on for the MOT in late March), but too good a deal to turn down. Probably only going to run them this season as they are reasonably worn by winter tyre standards or might even change them to a better size of winter tyre, but will be better than summer tyres, plus I use my satnav to give true road speed which is far more accurate than the speedo. Long term plan that I'm formulating is to refurb my 17s and run them with winter tyres once I've worn down the summer tyres over next summer or even two and then get standard tyres for the 18s. Cross climates on the 18s and sell the 17s...… Its a work in progress which budget and whim will determine eventually. Quote Link to comment Share on other sites More sharing options...
PaulQ Posted November 21, 2019 Report Share Posted November 21, 2019 18 minutes ago, ½cwt said: Stock is 318mm rolling radius and these are about 352mm so just over 10% My apologies if my maths is wrong, but are you sure ? 255/40/17 is 636 mm diameter and 275/45/18 is 705 mm which is a 69mm difference so a sidewall height increase of 34.5 mm Thats double what your suggesting..... Quote Link to comment Share on other sites More sharing options...
GmanB Posted November 21, 2019 Report Share Posted November 21, 2019 @PaulQ 35/18 stock on the rear to 45/18. I'd imagine you won't be able to drive the car very fast on 45/18, especially if your car has been lowered or on M030 springs. Correct me if I'm wrong but doesn't the 35 to 45 just add 10mm to each radius and hence adding 20mm to the diameter? This is tyre size we're talking. Quote Link to comment Share on other sites More sharing options...
PaulQ Posted November 21, 2019 Report Share Posted November 21, 2019 (edited) 17 minutes ago, GmanB said: @PaulQ Correct me if I'm wrong but doesn't the 35 to 45 just add 10mm to each radius and hence adding 20mm to the diameter? This is tyre size we're talking. No.The 35/45 is the aspect ratio, so the figure is the % of the tyres width. Use this to get some numbers. https://www.willtheyfit.com/ Edited November 21, 2019 by PaulQ Quote Link to comment Share on other sites More sharing options...
GmanB Posted November 22, 2019 Report Share Posted November 22, 2019 Urgh apologies, yes then it's a lot more than I thought. A 6.2cm diameter increase on the rears. Quote Link to comment Share on other sites More sharing options...
el 3.2S Posted November 22, 2019 Report Share Posted November 22, 2019 275/45 18 is nearly a 4x4 tyre, I have 285/50 18 on the ML55. Quote Link to comment Share on other sites More sharing options...
Patt Posted November 22, 2019 Report Share Posted November 22, 2019 It is exactly a Panamera tyre as had to have "N" rating for warranty and was stuck for choice when needed. Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 22, 2019 Report Share Posted November 22, 2019 11 hours ago, PaulQ said: My apologies if my maths is wrong, but are you sure ? 255/40/17 is 636 mm diameter and 275/45/18 is 705 mm which is a 69mm difference so a sidewall height increase of 34.5 mm Thats double what your suggesting..... You are quoting diameter, I am quoting radius, hence factor of 2 discrepancy... The ratio of differences is the main factor. (I just find it easier to work with one profile i.e. the number on the tyre and add half the diameter converted to mm). I'm a 2pr man rather than a pd man. Anyhow when I bought them and was fully aware of the size issue and @Patt will tell you I even had a print out check sheet for the sizes showing the difference. Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 22, 2019 Report Share Posted November 22, 2019 11 hours ago, GmanB said: especially if your car has been lowered or on M030 springs. Standard suspension so no problem there I hope. If there is it has sagged a lot and the cost of these will be the least of my problems...! Quote Link to comment Share on other sites More sharing options...
PaulQ Posted November 22, 2019 Report Share Posted November 22, 2019 10 minutes ago, ½cwt said: Anyhow when I bought them and was fully aware of the size issue and @Patt will tell you I even had a print out check sheet for the sizes showing the difference. Cool. Didn't want you to be disappointed Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 22, 2019 Report Share Posted November 22, 2019 8 hours ago, PaulQ said: Cool. Didn't want you to be disappointed To be fair the fact the rims have winter tyres on them that can be used even if not ideal sizes is a bonus, it is the fact they are 18" 996 GT2 rims to upgrade from my standard 17s that made me buy them😀 Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 24, 2019 Report Share Posted November 24, 2019 On 11/22/2019 at 8:04 PM, ½cwt said: To be fair the fact the rims have winter tyres on them that can be used even if not ideal sizes is a bonus, it is the fact they are 18" 996 GT2 rims to upgrade from my standard 17s that made me buy them😀 Typo, GT3 style rims, not GT2. However as I suspected might be the case with the bigger winter tyres they don't go on, they just foul on the spring platforms on the shock/strut assembly, so plan B is to run out the rubber on my 17" rims over the next 12 months or so, then get new summer rubber in the correct 986 sizes (225/45/18 & 265/35/18) and fit winter rubber on my 17" OE rims going forward. In the mean time anyone want a pair of 30% worn 235/45/18 N rated winters or a pair of 65% 275/45/18 N rated winters? I'll post this elsewhere too. Quote Link to comment Share on other sites More sharing options...
Huw_L Posted November 24, 2019 Report Share Posted November 24, 2019 7 minutes ago, ½cwt said: Typo, GT3 style rims, not GT2. However as I suspected might be the case with the bigger winter tyres they don't go on, they just foul on the spring platforms on the shock/strut assembly, so plan B is to run out the rubber on my 17" rims over the next 12 months or so, then get new summer rubber in the correct 986 sizes (225/45/18 & 265/35/18) and fit winter rubber on my 17" OE rims going forward. In the mean time anyone want a pair of 30% worn 235/45/18 N rated winters or a pair of 65% 275/45/18 N rated winters? I'll post this elsewhere too. Not sure how 'just' we're talking, but if it's only a couple of mm, some cheap spacers may well sort you out. Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 24, 2019 Report Share Posted November 24, 2019 Just now, Huw_L said: Not sure how 'just' we're talking, but if it's only a couple of mm, some cheap spacers may well sort you out. Thought about spacers but as the rears just rub when static and the fronts are only about 1mm clear I'd need to go to 7mm spacer to ensure dynamic clearances, even then with the rear tyre size I'm not sure the wheel arch clearance would have been good enough and I don't want to risk bodywork damage. A set of longer bolts and spacers would be about £200 which is more than 1 new rear tyre cost so starts to eat into the tyre replacement budget. As I noted before, I really only wanted the rims not the tyres when I bought them. If the tyres had worked out, bonus. So you win, some you lose. I'll just have to wait a bit before I fit them (when it will look gorgeous, the one I fitted on the front left did look fantastic and almost made my cry 😥 when I realised it was going to have to come off again) but I've always planned this car as a long game. Quote Link to comment Share on other sites More sharing options...
John2000 Posted November 24, 2019 Report Share Posted November 24, 2019 Bad luck Chris I was looking forward to the pictures but as you say they are cracking wheels so worth the wait. Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 25, 2019 Report Share Posted November 25, 2019 (edited) OK, I've joined the village idiot club. After messing around with my new wheels yesterday I left the key in my working trousers which has now been through a nice cool wash overnight. Transponder unit, without battery, now sitting in a bag of rice near a radiator and I'm hoping... Maybe time to get the second key sorted even if this one survives, basically the transponder seems shot but the red light does flash, hover the body of the key won't clip closed, I guess it was the mainly used key before I got it with the one I've washed usually being the spare. Also intriguingly the windows were open this morning (definitely close when I locked it up last night) so I'm also drying out the interior as it rained overnight. It did at least make it easier to unlock the car without triggering the alarm. A little less happy with my Boxster now than I was 24 hours ago Edited November 25, 2019 by ½cwt Quote Link to comment Share on other sites More sharing options...
Menoporsche Posted November 25, 2019 Report Share Posted November 25, 2019 Quote Link to comment Share on other sites More sharing options...
John2000 Posted November 25, 2019 Report Share Posted November 25, 2019 1 hour ago, ½cwt said: A little less happy with my Boxster now than I was 24 hours ago Ho I'm sorry to read this hope you get sorted quickly and can put this behind you so you can enjoy you boxter again. Good luck Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 25, 2019 Report Share Posted November 25, 2019 27 minutes ago, John2000 said: Ho I'm sorry to read this hope you get sorted quickly and can put this behind you so you can enjoy you boxter again. Good luck Nothing some time and money can't fix. Quote Link to comment Share on other sites More sharing options...
John2000 Posted November 25, 2019 Report Share Posted November 25, 2019 2 hours ago, ½cwt said: Nothing some time and money can't fix. Hope not too much money. Re your comment about your windows "Also intriguingly the windows were open this morning (definitely close when I locked it up last night)" Don't know if you know this but if you hold down the unlock button on the the remote key a little longer than normal or will hope both windows, useful on a hot day. How far away is your washing machine did the key when wet send a single? Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 25, 2019 Report Share Posted November 25, 2019 I'll be impressed if that is the case it as the key only works from about 8 metres away and the washing machine is at least twice that and though 2 walls. However seems a reasonable explanation. Just my luck the key over performs as it is being washed and it is raining outside... Quote Link to comment Share on other sites More sharing options...
Russjmills Posted November 25, 2019 Report Share Posted November 25, 2019 (edited) Lobbed out £520 notes on Michelin ps4s Edited November 25, 2019 by Russjmills Quote Link to comment Share on other sites More sharing options...
John2000 Posted November 25, 2019 Report Share Posted November 25, 2019 32 minutes ago, Russjmills said: Lobbed out £520 notes on Michelin ps4s I did the same a few months back but I was stupid and let the same tyre garage do a four wheel alignment or should I say out of alignment more like Lee at CPS re did them and they been really good on my current road trip as it rained from England to well passed Paris and in Spain it been blue sky and top down and they feel really good. Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 27, 2019 Report Share Posted November 27, 2019 On 11/25/2019 at 1:43 PM, ½cwt said: I'll be impressed if that is the case it as the key only works from about 8 metres away and the washing machine is at least twice that and though 2 walls. However seems a reasonable explanation. Just my luck the key over performs as it is being washed and it is raining outside... Please to report that after leaving my (now nice clean) key transponder in a bag of rice near a nice warm radiator whilst I've been working away for the last couple of days, all it well and it still works. Phew! Only a little time and no money @John2000 Getting happier with my Boxster again Quote Link to comment Share on other sites More sharing options...
John2000 Posted November 27, 2019 Report Share Posted November 27, 2019 53 minutes ago, ½cwt said: Getting happier with my Boxster again Really pleased the read this on a wet and windy night in Bilbao. Quote Link to comment Share on other sites More sharing options...
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