Factory Tires - How much mileage? Options

[Scotts-GTR]

i did a 3/4" drop, and more aggressive camber. The more aggressive camber will help your turn in and result in less understeer. if you can tune the understeer out, the tire wear is a lot less. Let us know how you make out. I cant wait to get a set of real tires on this car.... Grrrr.

[Neoseven]

i did a 3/4" drop, and more aggressive camber. The more aggressive camber will help your turn in and result in less understeer. if you can tune the understeer out, the tire wear is a lot less. Let us know how you make out. I cant wait to get a set of real tires on this car.... Grrrr.

Real tires are on the way for 20" which is where I am staying. Bridgestone has them already in Japan, just not here yet, you saw them on the Nismo car. Toyo will probably be the first to release here, but something is not right about what they did. The tire the showed at SEMA needs a wider wheel front and rear to work. Not sure what they were thinking, or why they did this. I really wish they would have just designed a tire to work with the stock wheel.

For now, I am switching to the Dunlop SP 600 as repeated reports give this tire the advantage.

My car is sitting at -2.5 degrees front, -2.4 degrees rear. As you know, there is not a lot of room in the stock suspension for this kind of adjustment. I have gone to the maximum the stock suspension allows in adjustability in regards to camber so if it isn't working out, I can either raise the suspension, or start looking for aftermarket, or custom suspension components to give me the adjustability I want.

[AutoXGTR]

For now, I am switching to the Dunlop SP 600 as repeated reports give this tire the advantage.

My car is sitting at -2.5 degrees front, -2.4 degrees rear. As you know, there is not a lot of room in the stock suspension for this kind of adjustment. I have gone to the maximum the stock suspension allows in adjustability in regards to camber so if it isn't working out, I can either raise the suspension, or start looking for aftermarket, or custom suspension components to give me the adjustability I want.

You were able to get that much negative camber from stock adjustments? Very good for the front but I wonder about setting rear to slightly less like -2.0 degrees since more negative in back increases understeer. Could even go as extreme as -2.5 in front and -1.5 in the rear for negative cambeer- you'd have to track test it or check run times for various types of driving from slaloms to different speed cornering. With more negative camber you get a bit of inner tread tire wear.

Another idea is to use a Max Summer tire like Goodyear Eagle F1 Asymmetric and use the same sized tire on GTR front and rear. 295/30-20 fits rims 10-11" wide so fine for rears but a bit wide for the 9.5" fronts but might still be OK and non runflat for better comfort wear and performance for street use. $357 each at tirerack and 240 treadwear.

Another choice in non runflat Max Summer tires would be Michelin Pilot Sport PS2 a great street tire. Using the same one tire on front and back idea one could use
275/35-20 $382 each 220 treadwear and fits from 9-11" wide which is fine for stock rims. Tire diameter is good at 27.6". 255/35-20 is an alternative front tire size.

[mcduck]

anybody found availability or pricing better than Tire Rack?

Tire Rack - tires for GT-R

I most likely will go with Dunlop SP 600s next. I cannot justify Toyo R888s unless I have a dedicated set of track wheels. If I time this right, i can pick up my second set of wheels and two full sets of rubber at the same time (just after New Years).

[Neoseven]

anybody found availability or pricing better than Tire Rack?

Tire Rack - tires for GT-R

I most likely will go with Dunlop SP 600s next. I cannot justify Toyo R888s unless I have a dedicated set of track wheels. If I time this right, i can pick up my second set of wheels and two full sets of rubber at the same time (just after New Years).

Nope, tire rack is the place to go. I am at emergency status, so I got a local Nissan dealer here in Phoenix area to get a set of Dunlops for me at $50 higher per tire than Tire Rack. He told me his cost is almost identical to what Tire Rack sells for.

[Neoseven]

Neo...I cant wait to hear you understeer stories when you get back!
Its a real pity we cant get any decent tyres for the stock rims yet. I just wish TOYO would hurry with those R888s!
We tune the Team TOYO Australia Drift Car and have had the thumb screws out for some tyres, but they are telling me not until your US spring

Damn thing just wouldn't stop pushing. Fronts just weren't holding up any longer to what I wanted from them and the worse the tire condition got, the worse the pushing became. I was trailing the brakes deep just to keep speed up in the turns because hard on gas wasn't going to happen while the wheels were still turned. Needless to say, I managed to get approx 2 hours in on the track today at the cost of set of RE070R's that have a solid ring of cloth showing inside and are heading that direction quickly at the outside edge. (no steel belts yet, I am just at the cloth, but the rubber started coming off in chunks. Hell, I am going for another 15 - 20 minutes on them tomorrow just to end their life right.

One thing I found, for those of you wanting to learn how to handle your GT-R when it starts getting loose. . . . run your tires down and you will find out.

[Neoseven]

They served me well.

[Neoseven]

You were able to get that much negative camber from stock adjustments? Very good for the front but I wonder about setting rear to slightly less like -2.0 degrees since more negative in back increases understeer. Could even go as extreme as -2.5 in front and -1.5 in the rear for negative cambeer- you'd have to track test it or check run times for various types of driving from slaloms to different speed cornering. With more negative camber you get a bit of inner tread tire wear.

Another idea is to use a Max Summer tire like Goodyear Eagle F1 Asymmetric and use the same sized tire on GTR front and rear. 295/30-20 fits rims 10-11" wide so fine for rears but a bit wide for the 9.5" fronts but might still be OK and non runflat for better comfort wear and performance for street use. $357 each at tirerack and 240 treadwear.

Another choice in non runflat Max Summer tires would be Michelin Pilot Sport PS2 a great street tire. Using the same one tire on front and back idea one could use
275/35-20 $382 each 220 treadwear and fits from 9-11" wide which is fine for stock rims. Tire diameter is good at 27.6". 255/35-20 is an alternative front tire size.

I tired PS2's on this car, didn't like them. The Goodyear Eagle F1 is a good tire as well and were adequate on a vette I was recently driving. None of these tires, from my experience are going to give better results that either the stock Bridgestones or the Stock Dunlops on this car. The ones you are mentioning are just more street tire alternatives. I am just waiting for the Bridgestone or Dunlop R comps for this car.

Regarding the camber, No, that is as far back out as I could bring them after the suspension drop using the stock suspension adjustments. I would have actually liked to see approx -2 degrees front and -1.5 rear but that was not to be had.

[mcduck]

I tired PS2's on this car, didn't like them. The Goodyear Eagle F1 is a good tire as well and were adequate on a vette I was recently driving. None of these tires, from my experience are going to give better results that either the stock Bridgestones or the Stock Dunlops on this car. The ones you are mentioning are just more street tire alternatives. I am just waiting for the Bridgestone or Dunlop R comps for this car.

Regarding the camber, No, that is as far back out as I could bring them after the suspension drop using the stock suspension adjustments. I would have actually liked to see approx -2 degrees front and -1.5 rear but that was not to be had.

what are your thoughts on the R888s? Thinking those will be my track tires when I finally get an extra set of wheels

[Neoseven]

what are your thoughts on the R888s? Thinking those will be my track tires when I finally get an extra set of wheels

Unless they change something, they aren't going to work for me. The R888's that were on those cars at sema you will notice had huge, truck like sidewalls. That's because they were mounted on stock wheel widths and they needed a wider wheel. I think the R888 is going to be a great tire, but to me it looks like you are going to need new wheels to use them in say 20x10 front 20x11 or 11.5 rear. Talk to the guys at Axis, as they had to switch out wheels to fit the R888 especially in the rear.

Who knows, maybe it was just a prototype, and the finished tire will be an exact fit for the stock wheel.

[trumperZ06]

Check the early videos for mega tire howl. That coupled with a 25 min stint on the skid pad killed the fronts. backs are still ok.

Early, tire howl in turn 1, with a lot of understeer.

http://www.viddler.com/explore/ScottsGTR/videos/1/

Late, a lot less tire howl, because of Cobb suspension and new alignment.

http://www.viddler.com/explore/ScottsGTR/videos/5/

Your first setup shows a lot of understeer... car seemed to plow in the corners.

That Cobb setup certainly impoved the GT'R's handling.

Nice driving...

[amfaster]

I tired PS2's on this car, didn't like them. The Goodyear Eagle F1 is a good tire as well and were adequate on a vette I was recently driving. None of these tires, from my experience are going to give better results that either the stock Bridgestones or the Stock Dunlops on this car. The ones you are mentioning are just more street tire alternatives. I am just waiting for the Bridgestone or Dunlop R comps for this car.

Regarding the camber, No, that is as far back out as I could bring them after the suspension drop using the stock suspension adjustments. I would have actually liked to see approx -2 degrees front and -1.5 rear but that was not to be had.

How were the PS2's compared to the Bridgestones?

[mcduck]

Unless they change something, they aren't going to work for me. The R888's that were on those cars at sema you will notice had huge, truck like sidewalls. That's because they were mounted on stock wheel widths and they needed a wider wheel. I think the R888 is going to be a great tire, but to me it looks like you are going to need new wheels to use them in say 20x10 front 20x11 or 11.5 rear. Talk to the guys at Axis, as they had to switch out wheels to fit the R888 especially in the rear.

Who knows, maybe it was just a prototype, and the finished tire will be an exact fit for the stock wheel.

well, I will be buying new wheels, but was hoping those would be the street/for looks set. Going to need something to fit stock wheels for track. Guess I'll figure it out later...

[Neoseven]

How were the PS2's compared to the Bridgestones?

Bridgestones were better than the Michelin tire in my opinion. I am talking about grip, not comfort. If your goal is comfort, the PS2's win hands down. Nice soft ride on those.

[Martin Donnon]

Just saw those shots of your tyres Neo.....respect

[trumperZ06]

Damn thing just wouldn't stop pushing. Fronts just weren't holding up any longer to what I wanted from them and the worse the tire condition got, the worse the pushing became. I was trailing the brakes deep just to keep speed up in the turns because hard on gas wasn't going to happen while the wheels were still turned. Needless to say, I managed to get approx 2 hours in on the track today at the cost of set of RE070R's that have a solid ring of cloth showing inside and are heading that direction quickly at the outside edge. (no steel belts yet, I am just at the cloth, but the rubber started coming off in chunks. Hell, I am going for another 15 - 20 minutes on them tomorrow just to end their life right.

One thing I found, for those of you wanting to learn how to handle your GT-R when it starts getting loose. . . . run your tires down and you will find out.

Ummm... per your statement above...

You are cording the inside of the tires @ the shouder...



you are running way TOO MUCH negitive camber.


Take another look at your alignment... try to spread the wear & temp. across the width.... with more wear on the outside edge !!!

Have you taken tire temps. using a probe pyrometer... coming into the pits/hot ?

[Kickhard]

Just a quick question. Has anyone tried to go to a non runflat 20in tire? and is there any to fit the GTR? I think weight would be better as ride comfort?

[descartesfool]

I agree with trumperZ06. You have the wrong camber on those tires for the track. Even without a tire pyrometer (which you should use), even wear tells you all of the rubber is working and your grip is maximized. It is normal for the inside of the tire to wear a little faster if you have the right camber for cornering as the tires will get hotter on the inside while running down the straights, accelerating or braking due to camber. But you have way too much wear on the inside and you are just throwing away good rubber. You should typically have the inside hotter by 10 to 20 degrees than the middle and outside when camber is optimized for cornering when you come in the pits hot and measure. Don't stay stationary for long to measure hot tire temps as you need to move again to get the brakes cooled down and turbos too. Pyrometer will also tell you if you are running the right hot pressures. Only make small adjustments at one time, as when you go back out after a change, all of the tire temps (12 of them) will have changed. Too many adjustments and you will just be chasing your tail.

That is some expensive rubber to burn. I would try some adjusting, with height or camber changes to get it right. A tire pyrometer only costs $130 and that is not much compared to the cost of 4 tires with mounting and balancing. And a pyrometer will last forever unless you bend the pin, and that only costs $65 to replace. Compared to tires......

[Neoseven]

But you all seem to think that the wear you are seeing on these tires is 100% track use. Let us not forget the 8000 or so highway and city driving miles those tires have. Yes, unfortunately negative camber causes a lot of inside wear on your tires when your going in a straight line.

Sorry if you mistakenly thought that my car was a track car only. No, it's actually a daily driver, including driving it to the track so wear is going to be much higher on the inside on my street run tires. I am now setup with one set for street track use (Bridgestones for now), and one set for track only use so I can actually start to tell more accurately what I am doing.

So you understand, the car wasn't pushing bad until the tires were worn out. The more worn out them become, the more pushing, duh.

I will be dialing in my own car next time out at the track with a fresh set of tires for the track. Not high mileage street tires like the ones shown above. Like I said, they did their job well, got me from the east coast, to California, did an autocross, and a few days at Buttonwillow and several days of commuting, canyon driving, and local road trips. For almost all of those miles, they were at the factory race camber settings, which is a very small amount of negative camber. That alone, with all of those freeway miles was enough to run the inside edge smooth, not that it was too much negative camber.

I have a pyrometer and I will be checking my fresh, track only tires when at Buttonwillow later this month to see where I stand and how much, if any I need to adjust.

I am glad you are such an expert trumper but in your eagerness to take a swipe, but I believe you miscalled this one. You may want to go over to Japan and teach Powerhouse Amuse how to set up their car while you are at it. They are running the same settings as me.

[trumperZ06]

My car is sitting at -2.5 degrees front, -2.4 degrees rear. As you know, there is not a lot of room in the stock suspension for this kind of adjustment. I have gone to the maximum the stock suspension allows in adjustability in regards to camber so if it isn't working out, I can either raise the suspension, or start looking for aftermarket, or custom suspension components to give me the adjustability I want.

negitive 2.5 degrees camber on the front... is way too much for a modified street/track alignment using street tires.

Hoosier dot "R's" and either Hoosier or Goodyear slicks... for track use... YES

absolutely NOT for street tires.


Negitive 2.4 degrees rear... is WAY overboard... even for a track alignment.



Your Dec. 3rd post... where you say you :


" would have Liked to see approx. negitive 2.0 front, negitive 1.5 rear" ...

would work a lot better for street tires.


Now dial both front and rear negitive camber back ~ 1/2 a degree should be close to optinum using street tires.

Use a pyrometer (Probe Type) for fine tuning your alignment.



This post has been edited by trumperZ06: Dec 5 2008, 09:23 AM