This year, I'm getting dedicated drag tires, be it drag radials or all out slicks.

My car will be making somewhere in the vicinity of 450whp on a Mustang dyno, trapping 123-124mph. I run 255/40/17 RT-615's on lightweight 17x9 rims in the summer, and snow tires on my stock rims in the winter. At the end of last year, with 407whp, I was breaking loose the RT-615's inflated to 20psi... I know, they're not a drag tire. It's too dangerous for me to keep using them. The other major concern for me is that I am running out of gear. I have a Shep Ultimate Ratio tranny and I was already topping out 4th gear last year, trapping @ 122mph.

My options are:

1. Mount BFG Drag Radials (225/45/17) on stock rims
2. Mount Nitto 555R (245/45/17) on stock rims
3. Mount (or try to) Mickey Thompson 26"/7"/17" motorcycle slicks on stock rims
4. Buy new wheels so that I can run a wider tire (which tire? I have no idea)

Now, I put a lot of miles on my car, so I'm not gonna daily drive with these tires, they are for the track only... That said, here are my concerns:

1. The BFGs are going down in size, that means small contact patch but more importantly, I need to run out 4th gear over 8000rpm, which I'm not really a fan of (stock motor, stock valvetrain).
2. The Nitto's are a good size, but supposedly aren't worth using... they are allegedly some of the worst drag radials you can get
3. The MT Motorcycle tires don't mount easily, they are more dangerous, but they do improve my gearing situation
4. I don't want to spend money on wheels just to use them a few times a year at the drag strip

So... unless I'm missing something, I'm pretty much screwed. Honestly, I'll probably end up buying the Nitto's, because gearing is a major concern, fitment on stock rims is a major plus, and I'll just have to deal with the fact that they aren't the best tire out there.

Any other thoughts or things I missed? Can anyone chime in with their experience with the 555Rs and a decent powered car? Thanks in advance!

 

The M/T motorcycle slicks on a stock rim has a slightly larger diameter then Nitto 555R's. The Nitto's will give you an extra 2mph at the same rpm.

 

If my math is correct:

M/T is 124.1 mph in 4th @ 7500RPM, Nitto is 122.8 mph in 4th @ 7500RPM. So 1.3mph, or about 80-90rpm difference.

The Nitto is 2.65" wider, but obviously not as sticky/soft. It will be easier to mount/unmount (I will still have to use these rims for snow tires next winter). As much as I'd love to try the M/T's, I don't think it's realistic for my situation.

The BFG's, as nice as they are, are only good for 119.4mph, 3.4mph less and requiring about 220rpm more than the Nitto's.

 

What about the 215 MT ET Streets? Or are they to narrow? they fit on 17s and according to MT's website they can be mounted on a 8 inch wide rim (within specs...)

 

What model number is that? I don't see them on their site

 

Do you have the Evo 8 4th gear? If your still on the Evo 9 4th gear those figures are way off.

Now that I'm looking at your graph its completely off. At 126mph I was just under 8,000rpms going through the traps last time I was at the track. Your not going to get 132mph out of the M/T's even with an Evo 8 4th gear until around 8,600rpms give or take.

With the Nitto 555R's on the Evo 8 4th gear you will have to rev out to about 8100rpms to trap 123-124mph

 

I have an Evo VIII 4th, and I'm pretty sure the numbers are accurate. I used an online calc and confirmed using a spreadsheet I've had forever that has always given me accurate values.

7900RPM will get me to 129mph on the Nitto's. It only got me to 126 on the RT-615s, so this seems like a good upgrade. Last year I was trapping 122mph on the RT-615's without coming close to my 8000RPM rev limit, so my numbers check out.

 

Well then your Evo 8 4th gear must somehow be longer then my Evo 8 4th gear because your figures equate to higher trap speeds then my real world results have shown. Good luck.

 

What tires do you have? The M/T slicks?

The numbers I got for those tires were doing my own conversion from 26" x 7" x 17" to 175/65/17... I'm not sure if that's 100% accurate but it should be close.

 

I used the Nitto 555R's which are my daily tires all the way up to my 11.09@123.5mph and I crossed the traps around 8000rpms in 4th. Your not going to see anywhere near 130mph at 8k in 4th with the Nitto's. With the M/T motorcycle slicks I ran 10.80@125.97mph right around 8000rpms again.

I wish your chart was spot on as I would not be planning on shifting to 5th on my next time out at the track due to the alternative of ragging 4th gear out to 8700-8900rpms. Unfortunately for both of us, it's unrealistic.

 

Well, seeing as trap speed is the average of the light at the quarter mile and the one 66 feet before, you're actually going through the trap faster than what prints out on your slip.

I don't think I'll have any problems staying in 4th on the Nitto's if I plan to trap 123-124 with an 8000rpm rev limit.

 

With the Evo 8 4th gear you should be banging the limiter about 10ft before the finishline. It'll work.

 

i can use nittos for daily drive??? i started a thread long time ago asking for a good drag/street and every one says BFs.... but bfs are only a drag tire right???

 

where do you buy motorcycle slicks?? what website??

 

I ended up buying the Nitto's. Anxious to see how they work out.

I wouldn't daily drive drag radials... they are too soft for precise cornering and will just wear out in 5k miles.

I'll be daily driving on RT-615's, definitely happy with those after going through 2 sets, and they do last 15k or so