I'm hoping you might be able to help me out with some anorak work, I'm wanting to clarify a date that i can't find in my reference books.
I think that the Ghibli was made from 1966 to 1973. Ruote Borrani make a selection of wheels mostly 6.5X15 & 7X15 (and they also do 7.5" but i think that mighty be a bit more "special build").
We know that the Ghibli originally came out on the 205VR15 PIRELLI CINTURATO ™ CN72
I'm struggling to find any accurate reference, but i know that some of the later cars came out fitted with 215/70VR15 tyres, But i don't know whether it was Michelin or Pirelli and i don't know what date they changed over. My guess is 1972.
QUESTION NUMBER 1 - What date did Maserati start fitting 215/70VR15 tyres to The Ghibli
I know that the 215/70WR15 PIRELLI CINTURATO ™ CN12 came out in 1971. That one is easy.
Without doubt Michelin were making 70 profile XWX tyres in 1970, tyres like 215/70VR15 Michelin XWX. However thanks to chatting to people on FerrariChat forum, i also know they were making the same tyre in 1968 on the first Daytona, it was the XWX but at the time it was just called an X. I actually believe the XWX tread pattern started earlier than that, i think the XWX tread design started in 1966, while being called "X" but not with the low 70% profile because it hadn't been invented until 1968. Which raises the next questions:
QUESTION 2 - When the Ghibli did change to 215/70VR15 tyres was it Michelin XWX or Cinturato CN12 (there is a slight possibility it could have been Cinturato CN36, But i don't think so).
QUESTION 3 - Did they at the same time change from 6.5X15 Borrani Wheels to 7" wheels?
On the subject of size 215/65R15 and 205/70VR15 they are completely the wrong size. And you should not fit inner tubes in 65% profile tyres. And wire wheels need inner tubes.
The picture below shows the correct original 205VR15 Cinturato CN72 tyres that the earlier cars left the factory with. it is still being made by Pirelli, we are shipping them all over the world and the quality is excellent. (if you buy them on line the shipping is excellent value, most places it is free, but we can even ship a set of 5 tyres to places like Australia for only £ 150 and when you think how big they are that is pretty good value. or you can buy them from Stuckey Tyres in Aus).
The tyre on the right is a 215/70VR15 XWX, again no doubt an excellent tyre, i would think that currently these are probably the most popular classic Masser tyres. The tyre on the left is a 205/70VR15 XWX, showing that because the side wall height is only 70% of 205mm instead of the 80% that is the 205VR15, the there is 20mm difference in radius (25.4mm - 1"). making the diameter nearly 2 inches smaller.
When we took the above picture when there wasn't the CN12 tyres that we now have. (There is also a budget version 215/70VR15 PIRELLI CN12 (Vintage Car use only, no DOT or E Mark))
Published on 14/11/2017