Haven't been doing much of anything car-related for a while, but I got a chance to get over to Capitol last night to try out some different tires. They're Nitto NT05R DOT drag radials in 305/45R18 size for my 1320. I'd picked up an unused set earlier in the year for a pretty hefty discount vs what the original purchaser paid, so I figured they were worth trying out.

The SRT Demon came w/ Demon-spec NT05Rs in 315/40R18 that are different than regular production NT05Rs. Dodge and Nitto worked together to redesign the sidewall, but I don't know if they made tire compound changes, too. I've seen pics of the Demon-spec tires wrinkling on a hard launch, so I believe what was said about the sidewall redesign. A guy with a Demon with whom I've pitted at the track a couple of times has gone as quick as 1.39 60s on those tires w/ good track prep... but I've also seen him just spin hard when the prep's gone away.

Here's the tough part... I don't know how much of what I saw/felt last night was tire-specific vs a reflection of the track's surface prep last night. The crew dragged the track a couple of times during the session, but never re-sprayed it from what I saw.

Quick summary:
- got 5 passes and car never hooked solidly on any pass
- tried pressure from 20.0 down to 18.0
-- at 20.0 the car just spun hard
-- at lower pressures it felt like the sidewalls folded over, rather than wrap to absorb some of the hit
-- they did not hop on any pass, which is the benefit of having taller sidewalls than the factory 275/40R20 Nexens
- compound feels much harder than M/T ET Street S/S, and still a bit harder then the OEM fitment Nexens, although they definitely got "sticky" after the first burnout and stayed that way
- MPH down at least 1+ compared to slowest passes earlier this year; didn't weigh Bravado 18x10 wheel & NT05R combination, but I believe they're on the heavy side compared to what I've run before
- best ET was in the 12.2s at 111+ w/ a 1.80 60; typical 60s have been low 1.7s with 305/40R18 MT ET Street S/S or Nexens (at least when the Nexens don't just spin & hop)
- they drove like regular street tires set to 28 psi to & from the track, but it's a good thing I missed the rain that came through near home before I left the track about 11:30 PM

At this point, my conclusion is... I don't have a conclusion. When I bought these, it was thinking they might be an affordable alternative with better life expectancy than M/T ET Street S/S or R. Since I bought them, I noticed that Nitto discontinued the NT05R series a few months ago. Nitto now offers only their NT555RII series as a DOT drag radial, which they claim is a better all-around, including at the track. However, the new tires seem to be getting hit-or-miss reviews, so I'm not inclined to try those out at this time.

For what its worth, I had MT ET Street Rs on my scat pack challenger.

They were damn near idiot proof on a 12.0@114mph car. 1.75 60ft.


I have the 555R2s on my new Redeye, and I think they are great on the street. We will see how good they are this fall when I get a chance to run it at the track in some good air.

How was the air, density altitude, last night compared to when your car was faster

Figured they would be better, I've been 1.81 60ft on stock crappy Eagle F1's, 392 Charger.

Data from Friday night

Comparative data from some other passes earlier in the year. The altitude-corrected ET and MPH for the one pass I calc'd from Friday doesn't seem that much out of line w/ other corrected runs, so the low MPH is probably due to the DA being a little higher. I'd thought I'd run in even higher DAs this year, but guess my memory is failing me... again.

I got to Mason-Dixon last night for a second round of testing the Nitto NT05R. Track conditions were good in that the car hooked up on all 3 passes. However, the results confirm my thoughts that these tires simply don't work as well as other tires I've tested on my 1320. Here are the 60-ft ranges I've seen with the three different tires I've run (good passes only used for data):

Nexen 275/40R20 (9.5 x 29.0)
- Capitol: 1.680 - 1.775
- MIR: 1.749 - 1.774

M/T ET Street S/S 305/40R18 (10.5 x 28.0)
- Capitol: 1.714 - 1.746
- Mason-Dixon: 1.743 - 1.777

Nitto NT05R 305/45R18 (10.5 x 29.0)
- Capitol: 1.807 - 1.861
- Mason-Dixon: 1.816 - 1.854

I suspect the reasons the NT05Rs aren't working as well as I hoped are as follows:
1. Rubber compound; sticks when hot on good track, but overall noticeably harder than either the M/T (softest) and Nexen (intermediate)
2. Sidewall design; they don't feel like they "wrap up" like the M/Ts do; they felt good at M-D, but definitely seemed to "fold" the sidewalls at Capitol
3. Weight; they're heavy and tall, which I believe increases their rolling resistance...

Data from both test sessions below.

I wish I could read the small print

I blew it up some, hope this helps
Nevermind.

I run a 305 M/T R on 18" Bravados. For me, track prep is everything. On a well prepped track I can mash the pedal to the floor, get consistent 1.6's and dip into 10.90s. Other than that I have to add ballast or ease the pedal down. There's a local track here that is very stingy with traction compound so even slow cars have slicks on them.
You are going to make a choice about treadwear and longevity if your drive to the track like I do. And don't get caught in the rain.

Maybe this will display better...

Yep, the M/T in the same size as the Nitto is gonna be the better choice for track use. I was thinking if the Nittos showed well at the track, then they would be a reasonable option with better lifespan. But, they didn't, and Nitto doesn't even offer the NT05R any longer, so it's kind of a moot point. I'll wait for more feedback on the NT555RII, since I'm tired of paying to be the guinea pig for new stuff.


That's why my full set of spare wheels have MT ET Street front and S/S rear that I swap out for trips to the track. Oddly enough, M/T has dropped the S/S in the 305/40R18 size, so my next option w/ the S/S series is a 275/45R18 (same 28" height, about 1" narrower, and somewhere between 1-2 lbs lighter) or giving the 305/45R18 ET Street R a try. But the S/S is definitely more "street friendly" when it comes to driving on wet roads.

Thanks brad, that helped a bunch

That's a nice spread sheet. Where do you get your DA calc from? Guys on Hellcat.org are yakkin about DA all the time and I never really asked where they got it or saw it explained on any website.

Online DA calculator: https://airdensityonline.com/free-calcs/#weather. DA is a factor of elevation, temp and humidity; if you don't have absolute (uncorrected) barometric pressure, then you need to have the track altitude level to adjust for a corrected barometric pressure.

A "0" DA is no adjustment from standard rating; "4000" is representative of oxygen available at 4000' based upon standard conditions; anything "-xxx" is better air density than standardized conditions.

Same site has list of tracks w/ links to their current & forecasted atmospheric conditions: https://airdensityonline.com/us-track-list/?filter=222

For PA, this is what they list:
Beaver Springs Dragway, Beaver Springs, Pennsylvania
Keystone Raceway Park, New Alexandria, Pennsylvania
Lucky Drag City, Wattsburg, Pennsylvania
Maple Grove Raceway, Reading, Pennsylvania
Numidia Dragway, Numidia, Pennsylvania
South Mountain Raceway, Boiling Springs, Pennsylvania

I have an old "weather station" kit to take my own measurements at the track, but have been using ADO (Air Density Online) for capturing my data this year. At some point I'll use both and see how close the are.

Thanks Brad, I'll be lookiing that up!