Nitto 555R Extreme on GT40P2117

Rick Muck- Mark IV · 23rd May 2007, 09:04 PM

WOW!!!

Those look nasty sticky!

How do they work?

Rick

Rich E. · 24th May 2007, 11:20 PM

What size are they and do you have a side shot with the clamshell down?

Thanks in advance
Rich.

Mike · 25th May 2007, 12:08 PM

Well, they are a 15" tire, but at this time I'm not sure of the other specs. While I have not seen it personally with the rear section on, the builder tells me they fill out the rear wheel well awsomely.

Bill D · 25th May 2007, 12:38 PM

They look like they may be the 325/50R-15 tires. Very wicked looking.

Check here

Mike · 25th May 2007, 01:39 PM

They are a drag radial. A lot of the hot Mustangs are using them as a DOT approved tire on all four corners with no problems, except for the wear factor. Nitto also makes the NT555RII which is a road race tire, and looks identical, but is not availble in 15". Since I'll probably only put 2 to 3k mpy on the '40, and these are good for 15k or so, I'll replace every 4 or 5 years. Who knows how much tire tech will improve in 5 years.
I'm using a different type Nitto on the on the fronts

Mike Drew · 29th May 2007, 09:40 PM

Quote:

Originally Posted by Foowowee

They are a drag radial. A lot of the hot Mustangs are using them as a DOT approved tire on all four corners with no problems, except for the wear factor. Nitto also makes the NT555RII which is a road race tire, and looks identical, but is not availble in 15". Since I'll probably only put 2 to 3k mpy on the '40, and these are good for 15k or so, I'll replace every 4 or 5 years. Who knows how much tire tech will improve in 5 years.
I'm using a different type Nitto on the on the fronts

Note that these are a DRAG tire. I talked with the technical representatives at Nitto about these tires for use on a Pantera, and he confirmed what I suspected--they are NOT designed for sports car use. They are intended solely for the mission of launching a front-engined musclecar down a 1/4 mile dragstrip, and they have numerous engineered-in compromises which make them marginal for any other use, other than slowly limping said musclecar to and from the dragstrip. Although they look fantastic on a GT40 (or a Pantera), Nitto strongly discourages ANY sort of spirited cornering with these tires. If you are literally just going to use your GT40 as a cruiser, you should be okay, but if you plan any Sunday-morning backroads blasts, or track days, you should be changing tires first.

These are a very specialized tool, and should be appreciated for how excellent they are in their narrow area of competence, but at the same time, acknowledged for their total unsuitablity for anything else....

Mike · 30th May 2007, 09:59 AM

You hit the nail on the head. My intended use of the '40 is as a "cruiser".
"Spirited driving" in a car like this only draws police attention, and track use, in my opinion, just tears up your car. If I want to track, I'd rather just go to a school and abuse their vehicles.

Mike Norvilas
Homer Glen, IL

Mike · 29th April 2009, 12:35 PM

Randy, no, you can't have everything. See below a quote from a post I made in 2007

Mike

Quote:

Originally Posted by Foowowee

They are a drag radial. A lot of the hot Mustangs are using them as a DOT approved tire on all four corners with no problems, except for the wear factor. Nitto also makes the NT555RII which is a road race tire, and looks identical, but is not availble in 15". Since I'll probably only put 2 to 3k mpy on the '40, and these are good for 15k or so, I'll replace every 4 or 5 years. Who knows how much tire tech will improve in 5 years.
I'm using a different type Nitto on the on the fronts

mike · 29th April 2009, 01:36 PM

Quote:

Originally Posted by Foowowee

Randy, no, you can't have everything. See below a quote from a post I made in 2007

Mike

hey mike!
the only way your going to get 15k miles out of a DOT comp tire is if you trailer the car everywhere...

not that you probably care abt the mileage, just sayin....

i got 2k miles out of my rears on my noble, DOT comps...street driving.

i drive pretty aggressively though.

mike · 29th April 2009, 01:40 PM

Quote:

Originally Posted by Mike Drew

Note that these are a DRAG tire. I talked with the technical representatives at Nitto about these tires for use on a Pantera, and he confirmed what I suspected--they are NOT designed for sports car use. They are intended solely for the mission of launching a front-engined musclecar down a 1/4 mile dragstrip, and they have numerous engineered-in compromises which make them marginal for any other use, other than slowly limping said musclecar to and from the dragstrip. Although they look fantastic on a GT40 (or a Pantera), Nitto strongly discourages ANY sort of spirited cornering with these tires. If you are literally just going to use your GT40 as a cruiser, you should be okay, but if you plan any Sunday-morning backroads blasts, or track days, you should be changing tires first.

These are a very specialized tool, and should be appreciated for how excellent they are in their narrow area of competence, but at the same time, acknowledged for their total unsuitablity for anything else....

you are correct, but we are running out of options in a 15" rim size.
one thing where we can KIND OF get away with taking a few hot laps with these tires, is that our cars are very light. probably 800-1000lbs lighter than what the tires were meant to support. less weight equals less load on the sidewalls.
is this an "ideal" tire? no. but again, we have little choice.
i know some ppl who take some laps with these and said they were fine.
also, these are a speed rated drag radial, as opposed to bf goodrich which is not speed rated.

Mike · 29th April 2009, 02:05 PM

Mike, you should register for the MVP track day at Autobahn in Joliet on June 1st.
Apparently they will let you run the full 3.56 track on that day. It would be a good way to christen your GT40. I'll bring my 40 on that day but I'll just watch.

Mike

mike · 29th April 2009, 11:26 PM

Quote:

Originally Posted by Foowowee

Mike, you should register for the MVP track day at Autobahn in Joliet on June 1st.
Apparently they will let you run the full 3.56 track on that day. It would be a good way to christen your GT40. I'll bring my 40 on that day but I'll just watch.

Mike

june first....hmmmmm, thats a monday, mike! some of us a-holes have to work! haha....ill make it if i can. my car is basically complete, we just need to tune it, align it, and corner weight it. then put some miles on it and see what bolts shake loose..

. hopefully all will go without a hitch.
as of now, im waiting on my paperwork from the state. hassle.
hope to meet you soon though.
regards

Bill Musarra · 30th April 2009, 09:36 AM

These tires have been discussed elsewhere and also are included on the spreadsheet of 15s elsewhere on the forum. The tires are a bit tall for our cars(27") but I too chose them. I had heard form others the same arguments. I also heard that with the decreased weight they will work on more than straight line driving. I don't have mine on the road yet but that will change in the next month. I can tell you this though, if you don't have the modified flares the rear clamshell won't close. My DRB is a standard rear clip and on the 10" rims it sticks out past the fender edge by 1 1/2". When the car first arrived, it came with 295 Goodrich tires that fit real snug under the fenders with out any rub.

and the top of the flare is resting on the tire with about 2" of the mating surface of the clip to the body short. I didn't realize it until I took the car off its stand with the tires on. Worked great at full droop.

I have a set of flares on order and they should be here any day. I wanted the more flared rear clip anyway so it is working out fine for me. Now this is on a car that the rod ends for the rear suspension are pulled in almost to it narrowest settings and the suspension other than the ride height is aligned only to roll it around the shop.

Bill

Mike · 30th April 2009, 01:47 PM

Bill, WOW! those things really stick out on you car. The SPF rear clip must be wider, because mine really don't stick out. I have the stock non flared clip and they fit with no modification whatsovever. I'll take a pic later today from the same angle if I get a chance.

Mike

mike · 30th April 2009, 01:53 PM

Quote:

Originally Posted by Foowowee

Bill, WOW! those things really stick out on you car. The SPF rear clip must be wider, because mine really don't stick out. I have the stock non flared clip and they fit with no modification whatsovever. I'll take a pic later today from the same angle if I get a chance.

Mike

i believe it will show it sticking out abt half an inch.

Mike · 30th April 2009, 02:06 PM

pic Well, they stick out a little.

Mike

Randy V · 2nd May 2009, 11:43 AM

Quote:

Originally Posted by Foowowee

pic Well, they stick out a little.

Mike

Mike

The MKII rear clip is a bit wider than the standard MKI rear clip I think...

Have you ever hit a really good sized dip or bum with those tires and still no rub?

Maybe the camber scrub in the suspension will pull the top of the tire in on BUMP far enough...