Settings For Nitto NT01s?

[Sleeper_08]

This is my third season tracking my car and I switched from 285/40/18 BFG KDW2s to 275/40/18 Nitto NT01 R-comps for this season.

Last weekend was my first time on R-comps and I am lapping faster but not as fast as I hoped.

Presently I'm running -1.5 front camber and about 1/8 toe in. I seem to remember reading somewhere that the R-comps work better with more negative camber.

Your suggestions on what to set the front end at, remembering that this is also my "daily driver", would be greatly appreciated.

 

[marksti]

This is my third season tracking my car and I switched from 285/40/18 BFG KDW2s to 275/40/18 Nitto NT01 R-comps for this season.

Last weekend was my first time on R-comps and I am lapping faster but not as fast as I hoped.

Presently I'm running -1.5 front camber and about 1/8 toe in. I seem to remember reading somewhere that the R-comps work better with more negative camber.

Your suggestions on what to set the front end at, remembering that this is also my "daily driver", would be greatly appreciated.

I ran -2 degrees ,

I would play with your hot tire pressures..mine worked best at 32 psi hot

BTW my tires lasted 12K+ miles and 15 track days

 

[SoundGuyDave]

Change that 1/8" toe-in to 1/8" toe out, and you'll be a LOT happier with the turn-in as well... My Hoosiers seem to like a LOT more pressure, up around 37 cold, 45 hot. I'm running -2.5* camber, but really, you should let the tire-wear (or temps, even better) tell the tale. If you start wearing the outside edges, either you need more pressure, or more negative camber.

 

[Sleeper_08]

Thank you your considered responses.

My backside is not terribly sensitive but it does feel like it is understeering more. After two hours tire wear was just to the tips of the sidewall diamonds on all tires except the left front. Tire pressures were around 39 hot front and rear.

The left has worn the diamonds right off. The track we were running, TMP, seems to be hard on left fronts.

With the NT01s I was expecting to see cornering lateral Gs above 1.0 G and I only touched 1.0 G once. There was a fair bit of time at 0.9 G. On a flat track should these tires corner at better than 1 G?

My plan is;
1) take the car in tomorrow and have the front set to - 2.5 camber and 0 toe
2) try to borrow or buy a needle type pyrometer by Friday or as a minimum get an infra red one
3) My brother and I are taking the car to Mosport, a high speed track, this Friday. He has over 10,000 laps there and will set my new Mosport benchmark on the NT01s. Last year on the KDW2s he got down to 1:42 and my best was 1:48.
4) The next time Marcus, a fellow with a similar car except running NT05s, and I are TMP, if it is OK with him;
a) have him drive my car for a few laps
b) put my data logger and video on his car for a few laps

 

[ArizonaGT]

Try -2.5 Camber up front to start, 32 front cold pressure, 31 or 30 rear cold pressure (might need to do one side 30, one side 31 depending on track direction).

I highly suggest investing in at least an IR Pyrometer to measure tire temps, this will help you get your camber dialed in very well on each track.

 

[SoundGuyDave]

+1 on the pyrometer, something I'm ordering tonight... Also, if you haven't try running your front swaybar at a setting one notch softer than you are now, if possible. That will help with the pushing a bit. Also, R-compounds can require a slightly different driving approach, at least at corner entry. Do NOT let them push, you'll scrape the rubber right off the outside edge of the outside front.

As far as your data goes, I would like to suggest that you can carry more speed through the corners (get on the gas sooner after turn-in, or trail-brake to help the rotation), since .9G is seriously in street-tire range. With the Hoosier R6 tires, I'm throwing peak G readings in excess of 1.7, and getting consistent 1.1G readings on the Dunlop *specs... I think doing data comparisons of you and your brother and your buddy, all in the same car, will be eye-opeining. Look for the following: coasting periods (just don't do it!! stay in the gas, or get on the brake, no coasting allowed!), braking points and rates, and turn-in speeds. Then, compare your numbers to theirs, and start really thinking about what that means: the car can do it. If your brother is running 6 seconds a lap faster, in your car, that means that you are giving that much time up. Use the data to find it! Understand, I'm not advocating just throwing the car into any given corner, but if you are entering at 60, running pure maintenance throttle all the way to track-out and then going WOT, but your brother is entering at 60 as well, but starts to accelerate right after turn-in, that could be worth .5 seconds right there. Multiply that .5 seconds by 12 corners, and there's your differential. Same entry speed, just getting on the gas sooner and harder.

 

[Sleeper_08]

SoundGuyDave

Have you been looking at my left front".. you'll scrape the rubber right off the outside edge of the outside front."?

There is one slow corner at TMP that I think was contributing most to the wear on the left front. I've started trying to get the entry speed under control and then getting on the gas faster.

My front bar is adjustable and right now is set to the middle so I'll give the softer setting a try. It also makes the Stranoparts adjustable rear bar more interesting as mine is non adjustable.

At Mosport last year my time improved considerably mainly by getting my turn in speeds closer to my brother's. Once we have the data for him on the R-comps then I'll be able to raise it another notch or two

One thing I did notice last weekend was that I am getting on the throttle faster with the R-comps. I was having to shift up a gear in places where it wasn't required before.

Can't wait until Friday for Mosport

http://www.mosport.com/trackmap.htm

 

[SoundGuyDave]

Nope, I didn't peek: I did the same thing with my first set of R6, the extra speed coming into the slow corner takes a bit of re-thinking in terms of braking point! I also find that I can turn-in a little earlier, at a little higher speed (closer to a momentum line, less of a late-apex power line), as long as I'm not scrubbing the front end...

The bar change may do you a world of good! A slightly softer bar will give you a bit more front grip, effectively freeing up the rear a touch. This WILL help you to rotate the car at entry, and makes for a noticeable difference. FWIW, I'm running Sam's bars, and while I'm still experimenting with the tuning, full soft up front, and medium in the back allows me to throttle steer the car into just about any attitude that I want, which is a VERY reassuring feeling!

The extra speed at the end of the straight (the extra up-shift) may not necessarily be from you getting on the gas sooner, it could easily be from overall higher cornering speed due to the extra grip. A little higher entry speed, even with the same throttle technique, combined with more grip mid-corner and no shenanigans on exit WILL result in a higher corner-exit speed, and that translates to more speed at the end of the straight. Take a look at your data, and make sure that you're ACTUALLY booting the car in the ass sooner! There are all kinds of benefits to being on the gas sooner: !) the car is more stable in the turn, B) you can start throttle-steering the car around the corner (less wheel input means less scrubbing of speed!) and C) you can immediately start gassing it to the point where the rear just hints at stepping out, without waiting for the track out. All of this will generate more exit speed!

I can't wait to hear about your outing to Mosport!

 

[Sleeper_08]

....I can't wait to hear about your outing to Mosport!

I tend to be more conservative at Mosport as there is more to hit and it is hit at higher speeds. All part of complying with objective #1 which is to drive the car home.

That said running R-comps at the same level of conservatism as KDWS should result in lower lap speeds.

Just to remind you of what Mosport is like here is a video from last year

http://www.youtube.com/watch?v=KYgjaztqFdw

 

[SoundGuyDave]

Oh, trust me, I know EXACTLY what you mean!! First "real" event for me was Gateway, a Roval outside of St. Louis, a little over a 300-mile drive to get back home, and there is NOTHING but concrete in any particular direction:



Still a lot of fun, though!! Particularly when the "red mist" descends, and you push a little harder than is probably completely sane... The car ahead of me set the TTU track record that day, Saturday, and I wound up stealing it away on Sunday...

We both know that we need to respect the tracks, BUT, we also have to have some faith in our cars, and our skills, and learn to gently push the envelope a bit, and not just stay complacent. I'm honestly not suggesting that you try to brake later, or start trailbraking if you're not comfortable with the dynamics of the car, however, that whole "back on the gas early" think is a win-win deal. The car WILL be more stable in the corner, and you have the control over how much throttle you feed in. Later braking will (maybe!) gain you a couple of thousandths, but getting on the gas sooner can gain you a couple of tenths, or more...

 

[Flash_of_Yellow]

Damn, did that guy in the video get a spare wing from a Cessna? That thing is huge.

Nice video Dave.