Pirelli Rosso...difference between N3/4 & MO?

[POR_NT]

Does anyone know what the difference is between the Pirelli PZero Rosso N3/4 and MO tyres?

I know that N3/4 are deemed most suitable for Porsches, and the MO's for Mercs, but what's the actual physical difference?

TIA.

 

[Richard_Hamilton]

I would check the load rating. N rated rears are often a higher load rating than non-N.

 

[Melv]

Figures ......stiffer side Walls on the N Tyres, and tested by Porsche!

 

[POR_NT]

Curious, as the MO tyre states "Extra Load", and could be fitted on the likes of CLK, CL,S....etc...so it might appear that the "MO" rated tyre could have a stiffer side wall then the N rated tyres...

 

[38F3E1]

Each tire will have a specific load rating stamped on it to do a direct comparison. Wikipedia explains how to decode it http://en.wikipedia.org/wiki/Tire_code#Load_index

Ian.

 

[Richard_Hamilton]

I "just" looked this up on a few tyre sites for Pirelli P-Zero Rossos:

225/40/18:
Standard: 92 (Load Index)
Mercedes: 92
Porsche: 88 (ie lower than standard!)

265/35/18
Standard: 97
Mercedes: 97
Porsche: ?? - Couldn't find any in stock anywhere, nor was there a load index shown in the places I did find them listed.

 

[A Croft]

Porsche are not the only manufacturer to use a sidewall marking on the tyre to designate homologated brands/ patterns. other manufacturers include BMW (*), Bentley (B/ B1), Aston Martin (AM8), Renault Espace (A), Peugeot (P), Jaguar (J), Ferrari (K1/ K2) and many more besides!
The difference is usually minor compounding differences in the various components used in the manufaturing process (see www.maxxis.com then automobile/ light truck then "how a tire is made" for info on the whole process if you're interested!) which "tune" the tyre to the different characteristics each vehicle manufacturer is looking for.
For many vehicle manufacturers it is not such an issue to fit non homologated product at replacement, providing you do not mix across an axle. This is partly because as a vehicle is used and suspension parts etc wear, at 20,000 miles the non homologated product will perform equally well. With a high performance sports car this is rather different. It does not mean that a set of non N rated tyres will not perform equally well in performance terms - just that they have not been homologated as an OE fitment by Porsche.