Nitto Nt01 air pressure

[RR711]

What's the word on the preferred air pressure for Nt01's? I just replaced a set of Toyo R888's with the Nitto's. I will be doing DE followed by time trials this weekend. (74 911 widebody 3.6 conversion 2800 lbs 225 45 17 and 275 40 17 with ambient temps in the 80's. Any suggestions?

[175K911]

FWIW, I swapped from R888 to NT01 and never looked back. I'm running 235/40-17, 255/40-17 on a 2500 lb '86 Carrera track car. With the R888 I ran 36/38 front/rear. With the Nittos I run 32/31 cold, yes more in the front than the rear. When hot I'm at 37/37. Another friend with a G50 Carrera runs the same cold temps as well.

Just for the heck of it I threw my R888's on this past weekend at Blackhawk and after just one run session I pulled them off and threw them back on the trailer. The Nittos are so much more fun to drive.

[Jack Olsen]

Below 30 hot.

[glewis80SC]

32/34 hot.

[175K911]

Originally Posted by Jack Olsen

Below 30 hot.

Are you serious? Explain. Everyone I know running the Nittos is above 30 cold, let alone hot. But I'm always looking to try something new for an edge.

[Mike Metzler]

I am intrigued as well by Jack's very low pressures. My NT-01 experience echos Ed's very well, although I prefer even higher hot pressures. Last month at Mid-Ohio I did some unintentional experimenting, coming in off the first session with the pressures 36/35 f/r. The handling was very bad, with the normal precision gone. I bumped the hot pressures to 37/38 f/r, knowing some folks (Hi Ed) liked lower pressures than the 40/40 I normally run, and things were much improved. The third session I went on up to 40/40 and the car was great again. For reference, this is an '87 Carrera, 23/33 torsion bars, TRG sways, Fox shocks, ~2750 lbs with me in it and ready to go.

Ed -- something to shoot for next season -- I finally got into the :42s. Just, as in 1:42.98.

Mike

[KTL]

Originally Posted by Mike Metzler

I

Ed -- something to shoot for next season -- I finally got into the :42s. Just, as in 1:42.98.

At Blackhawk? That's pathetic...........

[Mike Metzler]

Ouch! I figure that if the bar is set too high I will never reach it!

Blackhawk is on my list of tracks that I have yet to visit, but plan to. Perhaps I can get a 42 there as well...

Mike

[glewis80SC]

Tried them at 36/38 hot and the handling was bad,dropping the pressure and she was back to normal. 80SC with 22/28 Tbars, smart racing sways 225/275x17's.

[450knotOffice]

I'm finding that lower seems faster with my NT-01's.

[175K911]

Originally Posted by Mike Metzler

I am intrigued as well by Jack's very low pressures. My NT-01 experience echos Ed's very well, although I prefer even higher hot pressures. Last month at Mid-Ohio I did some unintentional experimenting, coming in off the first session with the pressures 36/35 f/r. The handling was very bad, with the normal precision gone. I bumped the hot pressures to 37/38 f/r, knowing some folks (Hi Ed) liked lower pressures than the 40/40 I normally run, and things were much improved. The third session I went on up to 40/40 and the car was great again. For reference, this is an '87 Carrera, 23/33 torsion bars, TRG sways, Fox shocks, ~2750 lbs with me in it and ready to go.

Ed -- something to shoot for next season -- I finally got into the :42s. Just, as in 1:42.98.

Mike

Stop raising the bar Mike! 42's with a stock engine 911 at MidO is quick. Where'd you find the time, any particular turn or just everywhere? I'm going to need to do some shock work over the winter to keep up with you now. I'm also intrigued by the fact that we both tend to start with about the same cold pressures but you build up a pound or two more hot than I do. Next time we chase each other around MidO we should compare temps coming off the track.

Originally Posted by KTL

At Blackhawk? That's pathetic...........

So Kevin, what would you consider a good time at Blackhawk for our 911's? Would high 19's be OK, with my student riding shotgun? In 40 degree temps on a cold track? Sunday morning it was 26 when I got to the track, but warmed up to the mid 40's and the track actually began to work OK. The air cooled and turbo cars loved the cold weather.

[Mike Metzler]

Stop raising the bar Mike! 42's with a stock engine 911 at MidO is quick. Where'd you find the time, any particular turn or just everywhere? I'm going to need to do some shock work over the winter to keep up with you now. I'm also intrigued by the fact that we both tend to start with about the same cold pressures but you build up a pound or two more hot than I do. Next time we chase each other around MidO we should compare temps coming off the track.

Where I found time might depend on what you are doing about power this winter 3.4? 3.6??

I agree we should do a temp/pressure comparison next time, and I am very curious about these reports of very low pressure on the NT01's. That is something I will need to try (I think).

[KTL]

I see you got the Octoberfest treatment- sub freezing morning. We had that the last two times I was there with PCA for their Octoberfest. That's some cold camping in a tent and sleeping bag!

Yeah 19's ain't bad in the snow........... Especially since my best so far is 1:22's in hot weather! Maybe an LSD and some stickier tires than Victoracers, and i'd keep you in sight for a few laps? Car's always a work in progress, so this winter should net a few more tenths here and there! Front struts and sway bar should help with some geometry/setup improvements

As far as the Nittos go, those will be my next choice of tire when the 17's go on my car. I'll be sure to report back with my findings too.

[175K911]

Cold temps are a love-hate thing at the track. Love the way the 911 makes power and keeps oil temps down. Hate the lack of grip, and not being able to keep the HT10's fully up to temp. But all in all, it was a great weekend.

[Peter Kelly]

I switched from MPSC to the Nittos. First time I ran them was in hot weather end of August, ran them about 38 hot and was less than thrilled. Went back to the Glen a few weeks ago and tried much lower presssures, (31 to 32 hot) and liken them a lot better. This is on a 89 Carrera track car. They are wearing right to the tips of the little triangle marks on the sidewall which is I am assuming what you want to shoot for.

Rear tires are deforming a lot based on pics I have seen, but the car drives pretty good on them. I think part of it is getting used to the different tire. So far I am about 2.5 seconds off my MPSC times at the Glen.

[Mike Metzler]

I will need to try the lower temperature route.

In my experience, the first session with new (unshaven) NT01s is lousy. They do not seem to grip at all, they are vague, they suck. However, starting with the next session -- and that can be as soon as 1/2 hour later -- and they work. That has been my experience with each new set. For what it is worth, driving ~500 miles on the street (to Watkins Glen) immediately after having them mounted made no difference. First session still sucked.

[glewis80SC]

Mike,
I had that experience at Willow Springs last time out, first run really sucked but second less than 60 minutes later they were great. I still love them though.

[fredmeister]

so in summation:
optimum pressure hot is 37-39 pounds.
take it easy the first session until a full heat cycle has been run in.
Anyone other than Jack O. run lower pressures with good results?
Can anyone comment on optimum camber settings, especially the front?

Will they run properly on camber limited to neg 2 degrees or so?

[jhelgesen]

I'll be trying my first set of nt01's this week at VIR. 225 and 255 x 17's on a +/-2400lb 911. Temps should be in the 60's during the day (40's at night). Car is about 1.5deg front 2.0 rear.

Tires are green, not shaved, so I'll be careful with the first runs. Let you know what I find out with pressures.

Switching from RA1's.

[peehonix]

I run 23 psi cold in the rear on 315/18's and 21 psi cold on 275/17 in front.

This is on a 2100 lb. car. -2.5 camber in front, -3.2 in the rear.