What tire pressure are other people with Nitto 555's running? The only thing it says on the tire itself is not to exceed 40 psi. The guy who mounted my tires said he inflated them to 30 psi and they definatly feel stiff. Anyway, I was on a back road last night practicing some launches and they spin launching as low as 1500 rpm. What is a good pressure for the street and what is a good pressure for the track? Any suggestions?

 

..would like to know this as well
-mike

 

mee tooo

 

Me Three I do hope he is talking about DRs.

 

Actually mine are the Extreme Performance ones not the Drag Radials. I plan on eventually getting slicks for the back for when I race. In the mean time I just want to know what is a good pressure for the street and what is a good pressure for the drag track on these tires.

 

me four

 

I e-mailed Nitto tech department about it. We'll see what they come back with.

 

After I bought my Nittos I had the same question. I found this on the web:

Changing the tire size or going to a plus-size fitment will change the required inflation pressure somewhat. Within the range of optional OE tire sizes, the vehicle manufacturer's recommendations should be followed. For sizes outside the range, the tire manufacturer should be able to help. (xxx brand), for instance, includes pressure recommendations for stock and plus-sizes, by vehicle, in its annual Fitment Guide, which your tire dealer should have a copy of. Typically, these are 0-3 psi higher for a Plus-one or Plus-two fitment.

I used this as a guide. The door sticker said 32 psi for the OEM 235/55-17 so for the 255/45-18 I went up to 35 psi. Seems to ride about the same as the 17's.

PS - the max pressure for my tires is 50 psi to carry the max load listed on the sidewall.

Greg

 

I still have not heard back from Nitto about what pressure they recommend. I have been running 30 psi on the street and the ride is nice. The problem is only when I try and launch the car. The tires break loose launching at as low as 1500 RPM (I still have the stock lower control arms). I am going to eventually try lowering the pressure to 25 psi and seeing what that does for my launch.

 

All tires are different....

I run Toyo T1Rs. On the street I run them around 40psi. Max is 45psi for this brand of tire. At the track, if I keep them at 40psi, I spin like crazy. If I drop them down to 28 psi, they hook a great deal better. I've tested this twice now. Each time I lowered the psi to 28, I bettered my time by .5 secs at least. Not to mention you can feel via the butt dyno.

Now on the flip side, my buddy is still running his stock P-Zeros. He hooks better with them fully inflated. If he deflats them, they don't hook on the track. I've talked to several fellow stang owners that echo this.

Once again... Each brand of tire is different.

 

Also, keep in mind the lower the pressure.... especially to 25psi the sloppier the handling. Under inflated tires tend to wrap around the rim.... I only lower mine at the track. Also, the door sticker is for the stock p-zeros tires. You should go by what it says on your tires.

Are you sure your tire don't have a psi range on them?

 

I certainly wouldn't drive around on them with low pressure. I am only saying I would lower it for the track so I am not worried about handling on the road if that is what you mean.

As far as the stock Pirelli's go...I didn't have them on long before swapping them for the Nitto's so I really don't know what to recommend as far as pressure goes. They aren't the best tires for drag racing so I would agree that you should just leave them as is when it comes to tire pressure.

There definatly is not a pressure range listed on my tires. All it says is not to exceed 40 psi.

 

I have BFG G-Force KDW 275-40-18's all around and had similar questions and concerns regarding tire pressure. I started out at 30, but found that handling suffered, but the ride was compliant. Stepped it up to 35, handling vastly improved, but was harsh. I have settled on 33 which feels right.

 

Nitto finally wrote back to me about the tire pressure question. Here was there answer: