wampire

hi guys,

I just installed Nitto nt05 tires on my 2012 C63. Size 245/35/29 front and 275/30/19 rear. guys wanted to put 35 PSI in all of them but told them to put 40 in the rear and 37 in the front till ill come home just to check cause Mercedes recommended pressure is above 40psi.
Well while driving home car feels like it floating on the road and doesnt have a good grip so do you have any suggestion what pressure to run on those tires.
Now ill go to the gym and will try to lower the pressure to 32psi just to see whats gonna be the difference.
On the 27th i have a track day and have to figure out what tire pressure to run on a track to or ill be the slowest guy there

Any help appreciated

mdgrwl

Brand new tires need a good scrub to get sticky. Put 50 miles of spirited driving on them and they will feel much better.

I used to run NT05's - they have pretty stiff sidewalls. I would run around 38-40psi tops.

wampire

I lowered the rear for a trial run to 32psi and feel much better but just manage to drive around the block cause im going on a trip in couple of hours so will continue to test when i come back. On 27th i have a track day so have to figure out at least a base for a track setup

PkB2014

nitto shows a load rating of 100 @ 50 psi

http://www.nittotire.com/Tire/nt05#size

OEM Conti has load rating of 95/94 so the Nitto can handle more load. There is some math to figure out the load rating at lower psi. No need to guess. I just didn't look for it too hard.

roadtalontsi

ya those tires werent really worth a crap on mine. the rears lasted 2500miles if that. Pretty disappointed figured they wouldnt last long but atleast hook up good, which they didnt. atleast they are relatively cheap. i was running 36front 38 rear.

wampire

Well i know they will not last long but if they hold good ill be happy. Toyo R888 were double the price so ill try them next time. Only problem i have is tire pressure. Mercedes recommends 44psi on mine and of course i didnt wanna inflate those tires to 44 but with 40 rear and 37 front, car was like floating on the road mot holding the road. Feeling was like when you have high pressure on a track so i lovered rear to 32 . Next will be to lower the front ones too when i come back from a flight. Will let you know about my tests

Strafe1

I had those tires on my c63 as well. They don't last long, about 6k on mine (rears). They hooked up great! A bit more road noise.

wampire

i sent email to nitto and got a reply nice support at least

The PSI recommendation for your vehicle would be listed as 42 PSI fronts and 46PSI rears for daily use.

For slightly better lap times the NT01 or NT555RII competition tires would be best suited for race track.
If using NT05 for track use, hot pressures in the high 30s seem to work well. Your starting cold pressures would depend on how much your tire pressures grow on track. We would not recommend using the NT05 above 40 PSI for track use.

The NT05™ is a max performance tire that was developed through extensive computer simulation modeling and on-track testing. These rigorous development procedures helped produce a street tire that provides precise and responsive handling and performance.

Please keep in mind these are general guidelines for setting up your vehicle and the NT05. The right setup for you would ultimately depend on what you feel most comfortable with.

Sincerely,
Nitto Technical Department

wampire

went to try that high pressure and guys please dont do it. car feels and handles very bad so im down now for a road on 38 rear and 36 front. still have to play with it but hopefully on 27th ill see what i can get on a track

PkB2014

The manufacturer is most likely making recommendations based on Load. So the question is, do you want to protect your wheels from pot holes, etc. ? If not, then the lower tire pressure may feel better for the winter months. The NT05 is not an all-season tire, so I would expect it to not feel so great in the cold weather. You might try the recommended tire pressure again once the weather warms up. Also, new tires are never as good as they will be after a few hundred miles. Once you put 100-200 or so miles on them maybe they will feel better.

wampire

Well im working in Abu Dhabi and at the momenth there is 24C temp so i dont have problem with outside temp except during summer when temp goes up to 50C.
What im saying is if you have the same tires trie that high pressure and you will see how the car is unstable and hard. By the way Conti which i got with a car they like that high pressure on the road but not on a track