275 GTB originality | Page 2 | FerrariChat

275 GTB originality

Discussion in 'Vintage (thru 365 GTC4)' started by Longstone Tyres, Apr 13, 2018.

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  1. miurasv

    miurasv F1 World Champ

    Nov 19, 2008
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    ....and acceleration/power from the engine.
     
  2. DWR46

    DWR46 Formula 3
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    Remember, the Michelin XWX was initially called the XVR in 1968. I think this was one of the first "V" rated tires. Ferrari was mounting them by the summer of 1968.
     
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  3. miurasv

    miurasv F1 World Champ

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    Wasn't that a Michelin model "X" that had a VR rating rather than model "XVR"? The VR rating must have been around in 1969 at least as looking at Braden and Roush's Daytona book there are some translated Build Sheets for Daytona #12775 dated 23rd July, 1969 listing the tyres as Michelin 215/70/VR/15/X. The Daytona shown at the 1968 Paris Salon had tyres with Michelin X painted in white on the sidewalls.
     
  4. turbo-joe

    turbo-joe F1 Veteran

    Apr 6, 2008
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    that is not really correct: the load capacity index and the speed index is important. there are several speed indexes - it start with N , max. 140 km/h and ends now at Z, more than 240 km/h, but the manufacturer says the max. speed. the speed index has nothing to do with the handling of the car. you may have for example V tires from manufacturer A and H tires from manufacturer B and find out, that the H tires are much better.
     
  5. miurasv

    miurasv F1 World Champ

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    I am well aware of there being several speed ratings, thank you, and my post was to emphasize the importance of the speed ratings. Your post contradicts itself I'm afraid. If a H rated tyre, which has been designed with a max of up to 130 MPH, is applied to a car with a higher speed capability, that H rated tyre is not going to be as good at keeping the car on the road on a long sweeping bend at 149 or 170 MPH or braking from those speeds as a tyre that has actually been designed to cope with the extra forces placed on it such as a V or a Z rated tyre. As an extreme example an H rated tyre will not be up to the job of coping with the acceleration, cornering ability and braking of a LaFerrari even up to 130 MPH.
     
  6. DWR46

    DWR46 Formula 3
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    Steve: Ignore what it said on the side of the tire. I went back and looked at a number of magazine photos of early Daytona's in 1969 and the tires on the cars "look" exactly like today's XWX, though the tire sidewall said XVR. This is also exactly matches my memory. Was there a difference between the XVR and the XWX, I am not sure, but it would take a Michelin engineer to tell us. As a matter of fact, I may still have some XVR's in the shop.
     
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  7. miurasv

    miurasv F1 World Champ

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    #32 miurasv, May 24, 2018
    Last edited: May 24, 2018
    Interesting, Dyke. Thanks. See here also for a Michelin "X": https://www.ferrarichat.com/forum/posts/142464205/
     
  8. miurasv

    miurasv F1 World Champ

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    #33 miurasv, May 24, 2018
    Last edited: May 24, 2018
    Daytona tyres as per Owner's Manual.

    Owner's Manual for the earlier Plexiglass Headlamp Daytona the tyres are stated as Michelin 215/70 VR 15 X.

    Owner's Manual for the later Pop Up Headlamp Daytona the tyres are stated as Michelin 215/70 VR 15 X or Michelin 215/70 VR 15 XWX.

    First pic from Plexiglass Daytona Owner's Manual and second pic from Pop Up Headlamp Daytona Owner's Manual.



    Image Unavailable, Please Login Image Unavailable, Please Login
     
  9. trkevin

    trkevin Formula Junior

    Nov 3, 2003
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    Any other photo's of the complete car? This is 275 GTB s/n 06449 at the Paris Motor Show in 1964. See my article in Cavallino Magazine 173 about this car. Haven't seen this photo yet.

    Best regards

    Kevin
     
  10. Longstone Tyres

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  11. miurasv

    miurasv F1 World Champ

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    Exactly!!! I've been telling people this for ages and they look at me as if I'm stupid reasoning that they never go over 100 mph etc. What they don't understand is that a tyre with a lower speed rating will not be up to handling the acceleration, braking, load placed on the tyres in cornering even at speeds well below the speed the incorrect tyre they have on the car is rated at.
     
  12. 3COL

    3COL Karting

    Jun 12, 2017
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    So in effect, if you have a 275 on 14 x 7, the only option is a 205VR14 XWX, which is to low of a speed rating to fit?

    What is the answer here, to have safe, but correct (or as correct as can be)?
     
  13. miurasv

    miurasv F1 World Champ

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    The XWX does not have too low a speed rating for a 275.
     
  14. 3COL

    3COL Karting

    Jun 12, 2017
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    Thank you Steve
     
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  15. Longstone Tyres

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    Speed rating is not a problem. they have a rating of W which is 170mph the rest of the detail about these tyres is on here https://www.longstonetyres.co.uk/catalog/product/view/id/1453/s/205vr14-michelin-xwx/category/2478/ including dimensions

    I suppose there is sort of another alternative tyre for the 14" Borranni https://www.borrani.com/ferrari-wheels/275-gtb.html which would be the 215/70VR14 XWX https://www.longstonetyres.co.uk/catalog/product/view/id/1459/s/215-70vr14-michelin-xwx/category/9093/ It would sort of be change for change sake.

    you would loose 28mm (inch and a bit 24mm in an inch) in diaameter, which i don't think is where you want to be going, for road use i wouldn't want to lower a 275 GTB, i don't think i would want more revs at cruising speed either. The wider foot print might track a little on uneven roads. it would lower the centre of gravity, a little making it a little more stable in some ways, but a little less progressive. Oo less comfort, which is also vibration absorption, so it is not so kind to the car.

    I wouldn't do it

    The other option is the 15" wheels on this 275 GTB/4 Borrani page https://www.borrani.com/ferrari-wheels/275-gtb-4.html That extra inch of rim in a 215/70VR15 tyre buys you that inch of diameter back, but you get the other issues of wider tyres and lower profile carcasses. there is more choice in tyres though https://www.longstonetyres.co.uk/tyres/215-70x15.html but they are not cheap either. 215/70VR15 seems to fit cars with V12 engines (& Maserati's), including the XJV12 saloon and if i had a penny for every XJV12 owner i had ringing me up and complaining about the price of their tyres i would probably have £ 2-62p. (i bought a beautiful XJV12 for £ 2,500 a few years ago. it was epic, it went like the clappers, a cheap way of having a V12 car)

    The speed rating thingy with Michelin XWX - back in the day V speed rating meant, it was a tyre that could be fitted to a car that was capable of over 210 kmh (149mph). at that point they hadn't invented W speed rating yet. Michelin as well as building the highest possible quality tyres are also very good at fashion, so in an attempt to make the tyres look just like they did in the day, they still call it a 205VR14 XWX, where arguably it should be called a 205WR14 XWX, or a 205R14 89W XWX. what the heck you could go further and call it a 205/80R14 89W. But what they do is put all the extra writing that they need to do for modern legislation on the side wall, but small and subtle so they still look right.

    So the 89W means it has a load rating of 580kg. so that tyre is capable of carrying 580kg at 170 mph for an hour continuously. there is a challenge!
     
  16. lancia

    lancia Formula Junior
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    The XWX is not the only 275 option for size 205VR14. Blockley Tyre offers their radial in full profile 205VR14. It has a dog-bone tread pattern similar to the Dunlop SP Sport that originally equipped many 275s.
     
  17. Longstone Tyres

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    I wouldn't consider that.
     
  18. lancia

    lancia Formula Junior
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    Could you give supportable reasons why the Blockley option, a VR rated tire in the proper size and profile should not be considered? (With all due respect and no offense intended, you do have tendency to recommend/promote only tires that you sell.......Blockley not being one your product offerings!)
     
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  19. Longstone Tyres

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    It is true to say i no longer sell Blockley Tyres, due to a series of reasons. I do get asked to sell them every now and again, but i don't want anything to do with them. But that is all business reasons that is not really what an end user should even care about. and i don't want to wash my dirty laundry in public.

    When it comes to performance i think the best thing to do would be read this article on Porsche tyres https://www.longstonetyres.co.uk/classic-car-tyres/porsche/911/classic-porsche-tyres-test-and-fitment-guide.html I don't think the XWX came out terribly well in this article, which surprised me. but there are a few things that aren't tested here that i think are Michelin strong holds and also aspects that the XWX is very good at.
    • Quality control. you don't get failed Michelin tyres. (I can only think of one issue with XWX tyres where they were perishing early, but after checking them, they had been repeatedly pressure washed using some pretty strong chemicals. Don't pressure was your tyres!)
    • The other one is durability, if you want to get one of your cars and hammer it round a track for a few hours you would want the XWX. it won't fall apart
    • if you are blasting along a motorway at high speed for a long time the XWX will give you excellent directional stability.
    • If you are going to jump in and drive a car on tyres that haven't moved for 6 months you want XWX.
    But Michelin didn't do terribly well in the wet. there is a bit of a balance when making tyres, and this strength and durability isn't a great help to wet use where you want it all softer. Michelin doesn't do well in the scoring, but from the descriptive text in the article, you would choose Pirelli or Michelin

    Anyway read the article and make your own mind up, but here are a few quotes that i use to build my opinion
    • Blockley's radial needed another 7 meters to stop.
    • The Blockleys surprise with sudden kick out of the rear axle while Vredestein lack crisp turning. Pirelli and Michelin are more harmonious through the bends.
    • Especially when the tyres from Blockley were straining for connection between the car and the road; with lack of lateral guidance and swerving back axle the driver experienced a roller coaster ride
    • Blockley led too some nerve-racking slides
    • With an additional braking distance on 16 meters (almost 4 car lengths) the Blockleys are definitely out of the running, modern standards are clearly lacking here - our verdict: steer clear.
    • and the English Blockleys are encountering problems, sliding an additional 4 car lengths when making stops on the braking track. Ultimately compared to modern technology these tyres are miles behind
    I should point out that this article was written in German, and i got a German freind to translate it for me, so you may feel i have put some spin on it, so i think i still have the original German one if you want to see it. But they are comparing them to modern technology, and the Blockley is modern technology. they are a wholey new tyre.



    This article does kind of back up my encouraging you guys to fit proper period tyre from top brands because all though the XWX doesn't do terribly well in the scores in the wet, i think this is the bit that really counts after being strongly critical of the handling of the Vredestein and Blockley they say:-
    "On the other hand the Porsche is well balanced on the road with Michelin and Pirelli" for me it is about the handling. then when they look right that is a bonus, as is coming from a quality brand. However the best thing is when you can have an OE tyre from a top brand, so it looks right, handles well and you feel confident its not going to let you down.

    I understand what you mean and i don't take offence when you say "(With all due respect and no offense intended, you do have tendency to recommend/promote only tires that you sell.......Blockley not being one your product offerings!)"

    I'd like to turn that round and say we sell what we consider to be the best tyres, and that way we can recommend them.

    I have always sold on quality, while at the same time allowing people to buy cheap tyres off me if they insist, but before they can do that they have to undergo a gauntlet of abuse on the phone if they want to fit a wrong sized modern carcass from a rubbish brand on a nice European Sports car. If you ring us up and start attempting to buy a white wall tyre for a European Sports car you are really going to get it in the neck. comments like "people will point at you and laugh while you drive down the street if you fit a white wall tyre on your XKE" i feel some times i have to save people from themselves. RING LONGSTONE TYRES FOR A BETTER CLASS OF INSULT! I am an old car enthusiast and keeping the cars handling nicely is imperative to me. we sell on quality, it is up to our customers to worry about their overdraft.

    I have been fortunate in the way my business has worked out. I always thought the Michelin Classic range of tyres was the best, and encouraged people to buy them, as a result of doing so, when Michelin wanted specific distributors to sell and stock, their classic range, we were selected, because with us their tyres don't end up on the wrong cars. And also as a result of doing so i have customers that are happy, because their cars drive well, long after they have forgotten their credit card bill. I've had Michelin on several of my classic cars and they are always miles better than what i take off.

    Then through the grape vine i heard that Borrani were looking for a UK distributor, and again because we are such nerds on what tyre fits what car we do very well for Borrani. Simon in our office is nearly as big a nerd as Matteo in Milano.

    And the most recent big and excellent development for us and the world of Classic tyres was Pirellli. They had made a whole heap of classic tyres that hadn't sold. I bought the lot and since then have been working with Pirelli to develop a small range of top notch classic tyres. These ones are particularly important to you guys
    https://www.longstonetyres.co.uk/pirelli-cinturato/ca67/185vr16-pirelli-cinturato-ca67.html this is pretty much the radial tyre Ferrari fitted to their road cars up until 1960 ish
    https://www.longstonetyres.co.uk/pirelli-cinturato/ca67/185vr15-pirelli-cinturato-ca67.html this is generally what Ferrari fitted between 1960 & 1964 cars like 250 GTE 2+2, GT Lusso, Road 250 GT SWB, etc
    https://www.longstonetyres.co.uk/pirelli-cinturato/cn72.html came out in 1964, and was the biggest tyre that was able to with stand the speeds of cars like a 500 Superfast, 330 GT 2+2 and pretty much the rest of the top Italian cars from Maserati Ghibli, Lamborghini Muira, ISO Griffo, Aston Martin DB6 etc. up until low profile tyres started coming in from 1968.

    So yes i do only recommend the tyres i sell. but Longstone sell the best tyres.

    Do i sound like an arrogant t**t? (I'm not going to ask my wife for a second opinion on this i know what she'll say)
     
  20. lancia

    lancia Formula Junior
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    Thank you for your detailed comment Longstone. No, does not sound arrogant at all, just a good presentation that you sell products that you believe in and stand behind. I appreciate the basis behind your cryptic caution about not considering the Blockley. I had not yet seen any kind of a test of the Blockley radial, and it is enlightening to see at least one tested assessment of their radial. I was aware of some concerns with the XWX in the wet. Again, no offense intended, but happy to draw out a reasoned critique. Do you know what the status is of the Pirelli Stelvio reproduction?
     
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  21. Longstone Tyres

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    The Stella Bianca is in the pipe line.

    A while ago now i was posted 3 different carcass structure of Stella Bianca, and i arranged a test session at my local track (Blyton). we tested the 3 different set ups and i had a couple of technicians over from Milan, and the best tyre was chosen. it was pretty unanimous. I had 2 cars and 3 drivers 2 of whom are very good drivers. all 3 of them independently chose the same tyres which was nice. so we are happy we have the right one. They will be crossply, but high performance.

    As far as timing goes. it is always impossible to estimate when a new production tyre will turn up. On top of that, this is also a very different kind of construction compared to what Pirelli make their normal road tyres, so i am less confident in giving estimations of timing. It should be this year, it could actually be next month. i wouldn't commit. the one thing i will commit to is that when they do get here i will be dead keen to let you know about it and get some sold ASAP.

    The first tyres will be a 600X16, which is an important size for '40s and '50s cars. in the '60s road cars tended towards radial more, so i'm not sure about making any 15" crossplys, however there is discussions about making a 590X15 for cars like the 125, 166, 195 and 212, but i'm not sure it will sell. my plan is that if the 600X16 sells, to follow this up with a 550X16 then maybe a 650X16. Then go a bit pre war with 550X18 and 600X19 for Alfa. this will not happen over night it will be tentative investment. so lets hope the 600X16 tyres are well received. they should be, Image Unavailable, Please Login the test tyres were great.

    developments should be somewhere on this page as it happens https://www.longstonetyres.co.uk/pirelli-cinturato.html
     

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