185 (OEM) Series vs 205 Series Tire?


(69 FHC ) #21

If we are referencing the “P” before the section width it refers to tires that are primarily designed for passenger car use.

From Tire Rack’s web site:

P225/50R16 91S

P = When a tire size begins with a “P,” it signifies the tire is a “P-metric” size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of P-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.

225/50R16 92S

If there isn’t a letter preceding the three-digit numeric portion of a tire size, it signifies the tire is a “Metric” size (also called “Euro-metric” because these sizes originated in Europe). While Metric tire sizes are primarily used on European cars, they are also used on vans and sport utility vehicles. Euro-metric sizes are dimensionally equivalent to P-metric sizes, but typically differ subtly in load carrying capabilities.

The full discussion can be found here: https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=46

If, on the other hand, we are talking about the “P” after the XVS" in Michelin tires that “P” means the tire has a protective area built in to the tire to protect the rim from curb rash.


(Pete Ingraham) #22

https://www.cokertire.com/185hr15-michelin-xvs-p-curb-guard.html It depends where the P is…for the XVS it means PROTECTION.


(Pete Ingraham) #23

Coker also shows a 185/70 15 XWX - looks to be 1/2" wider than the XVS - which may be a compromise?


(Longstone) #24

It is the XVS-P that is being discussed

This link shows all the good 185R15 tyres that you would consider for an XKE. https://www.longstonetyres.co.uk/tyres/185-15.html If you click on a tyre then it will give you all sorts of extra details about the tyre. such as heighth and width.

This link shows the 185/70VR15 tyres https://www.longstonetyres.co.uk/tyres/185-70-15.html
in theory the width of a 185/70R15 should be about the same as a 185VR15 (give or take a little. you will also notice differences between brands of tyre),
but the heighth will be approximately 10% of 185mm smaller in radius. also as you start getting lower like this then the tread is often a little wider in relation to the section width. But that is not such a great issue, if you stick with period tyres, but as you get more modern and lower it becomes more of an issue.
However 185/70R15 is totally wrong for an e-type. I know some of my competitors recomend it, but they are wrong.

205/70VR15 this page shows all the tyres we would sell in this size. https://www.longstonetyres.co.uk/tyres/205-70-15.html again click on a tyre it will show you the distention, which again vary from brand to brand. However 70% of 205mm is 143.5mm is about the same as 80% of 185mm = 148mm (ie not 70% of 185mm). which amounts to about the same diameter of tyre as the original 64.0_15 Dunlop RS5 which was 683mm when Dunlop still made it.

On this film it shows you all the tyres that we recomend https://www.youtube.com/watch?v=cioJAe2t8F4&list=PLORxf0xWk2NAz0J53D0dlFGi8rWwUOHYj&index=3 you can see the differences in tread width, and see the tyres in tthe flesh. But if you want to get yoour hands on them come and see us or arrange t o meet us at a VSCC race meeting.

205/70 tyres are over tyreing the car, which is why they didn’t fit them to the e-type in 1968 when it came out but waited until they fitted powersteering. there is a phenomena now where people are keen to fit a 205/65 or a 215/65 tyre or something of that ilk, because it is cheaper. The feeling that it is better is understandable, because of the perception that a modern tyre is better, which in some ways is true, but not for an e-type. a modern tyre suits different geometry. People then buy a new set of wheels, because you need a wider wheel to fit the lower profile tyre, which does cost less but will spoil your handling.

Of course because you are fitting a low profile tyre, you cannot use an inner tube. so you need a tubeless wire wheel. All cars that fitted wire wheels need inner tubes. I have seen too many failed tubeless wire wheels to trust them. Any tyre a discerning driver would want to fit to these cars would not be less than 70% profile.

It is a misguided rout to go down. Yes they are not cheap, but there are some great tyres in the right size for these cars. what you don’t want is to set yourself off down the rout of modifying you car to suit a modification that you did to make amends for another modification you did etc. etc…


(Bob Curran) #25

This is obviously a matter of opinion and one that I struggled with, but eventually I opted for the the original 185 tires and I have never regretted it. The car handles wonderfully and has a light responsive feel while cornering and at speed. There is really nothing that has to be improved upon, either in terms of performance or appearance, if you are not racing the car. And as someone who was taught to drive without power steering, it was common knowledge that it was much easier to turn the wheel, and better for the tires, suspension, steering gear etc. if the car was rolling while the wheel was turned.


(Pete Ingraham) #26

Thanks for the informative videos and discussion. I have just ordered the Pirelli Cinturato CA67 in the 185VR15 based on your discussions and recommendations from my local shop. They were pretty dear, but good tires (tyres) are insurance you collect on.


(Longstone) #27

I bet You love them.

i’d love to see some pictures


(Nick Saltarelli) #28

185HR15 Vreds on 6” wheels is the way to go, IMHO.


(David Ahlers) #29

So Nick, the wider wheels show the intuitive advantage of more tire on the ground, ie. greater traction. Mr. Longstone’s narrative is that situation is not the advantage it may seem to be. I have a tough time rationalizing that. But my Bridgestone 205x65x15’s on 6" daytons grip is far beyond my balls for street driving.

So how does your car handle? Can you drift it through the corners like a Goodwood racer?
I remember putting Pirelli Cintauratos on a Fiat and killing the fun factor because it stuck so well. Less is more?


(Nick Saltarelli) #30

David, the advantage of the 185s mounted to the 6” wheels is the original footprint is maintained with a slightly stiffer sidewall. Tire on the ground isn’t changed from the original configuration. The lightness of steering is maintained (I will depend on @John_Walker1 to testify to that since he’s driven my E) with to my eyes an improved aesthetic.


(Chris Fell) #31

I have had 195 and 185 width tyres on my car. I couldn’t tell the difference between them. If I ever fit 205 width I’m sure I’d still not tell the difference on the road, even when parking. Maybe that’s because I cut my driving teeth on cars that had no power steering, and have always made sure the wheels are rolling when I turned the steering wheel.

I don’t ever drive at the limit of the tyre’s adhesion. Given today’s traffic that would be stupid, and given the traffic laws in Blighty I’m sure my licence would become heavy with endorsements. If I wanted to put it on a track (I never will, but…) I’d change the tyres for more suitable compounds widths and profiles, and the suspension to reduce roll.

So the only reason I’d change tyres for a wider tread would be to make the car look less inept, to fill the wheel arches, to make it look more planted on the road. Make it more boxer than ballerina. The E-Type never was a wimp, but it needs to look the part. Wider tyres will do that.


(Longstone) #32

205/65R15 is too small in diameter (5% of 205mm = 10mm radius. nearly an inch in diameter.

When you change tyres. the ones you take off might easily not be up to pressure. so if you take off a 185 that is slightly low in pressure and fit a 195 at the correct pressure arguably the 195 could feel lighter. One of the other things that makes tyre comparisons difficult is you take off old rubber and fit new.

The science tells us that a period 185 is better on these cars. and a 185R15 Cinturato will not stop you as well in a straight line as a modern tyre like a 205/65, and you may have less wheel spin with a wider tyre. However in the corners a 185R15 Cinturato will be miles better because it is thinner with a more rounded cacrass, where your modern tyre will lift the inside edge and the loss of grip will be more sudden.

Back to the tyre comparison. if you take off an old perished, low pressure 185 and fit a correctly inflated 195 or 205 section tyre you might not so much feel it is a bad thing. However one thing i think i can very confidentially say is that everyone that takes off wrong size tyres and fitts either 185Vr15 Pirelli Cinturato or 185VR15 Michelin XVS is over the moon with it, they love the feel of the car being the way it should be.

Has anyone ever made this transfer back to the good stuff and not been really pleased with the results?


(Eric) #33

Most of the period photos that I have seen of E-types in race trim show wide, modern rubber…definitely not 185s at all four corners. The factory offered (recommended?) a 5.5 inch wheel at the rear and the very early race cars appear to have front tire diameter of the same size as a 205/65 and the rear diameter the same as a modern 205/70. I believe David Alhers post above is on the mark. The 185 tires give the vintage “feel”…along with the loss of grip and slip when cornering fast. Dollars to donuts the actual grip is far less than a modern tire. You get to feel like boy racer, but the car is relatively speaking…slow. Another anecdote…the fast autocross cars in recent years do not use 185 tires. My experience with 205/65 V rated Sumitomos on the front is that they provide massive grip and instant steering response …akin to my old Lotus Elan on shaved Pirelli P7s on 6" wheels back in my autocross days.


(69 FHC ) #34

I’d judge your car as very well sorted, obviously well maintained and quite a joy to drive. Yes, I noted the steering was lighter than my FHC with its 205s.