Will Nitto 555s in lower series fit?

[studio460]

I'm thinking of replacing the factory BFG G-Force KDWS tires with Nittos. I really want to lower the car's CG, and so I also plan on getting the Eibach front springs to assist in lowering the car as well. But I also want lower-series tires, front and back to improve cornering/handling even further. I am trying to keep the factory "rake" by offsetting the series front to back by "5." So, instead of a 50-55 series set, I am thinking of using a 40-45 series set. Make sense? I thought about doing a 35-40 series set, but I guess that might be too extreme for such a heavy car? Plus, it just might look too weird anyway. Unfortunately, Nitto doesn't make a "245/45-18." So here's what I'm thinking . . .

NT-555 EXTREME ZR
Ultra High Performance Radial
UTQG: Treadwear 300, Traction A, Temperature A
Z Performance Rated

Stock BFGs:
Front: . . . . . . . . . Rear:
235/50 ZR18. . . . 245/55 ZR18

Case A: Nitto NT-555s:
Front: . . . . . . . . . Rear:
235/40 ZR18. . . . 255/45 ZR18

Or I could try larger fronts with the Nittos:

Case B: Nitto NT-555s:
Front: . . . . . . . . . Rear:
245/40 ZR18. . . . 255/45 ZR18

Anyone tried these yet on a Marauder? Are there any clearance issues using the stock rims with these lower-series tires (and larger-front width in case "B")? Any suggestions or comments most welcome (because I can't wait to do this!). Thanks.

[studio460]

Oh, and the first number is the tire width in millimeters, right? So, I'm talking about a 10-millimeter, or 1 centimenter-wider tire which is a bit less than a half an inch (1 cm = 0.3937 inches).

[studio460]

Well, I just read in this in another thread originally posted by looking97233:

"Marauder S tire sizes: 255/45/18 front, 255/50/18 rear--Pirelli P-Zeros . . ."

Which I guess answers my question. I saw in another thread where someone put 305s on their blown Marauder! I can't believe those fit! The Nittos certainly are a lot less money that the Pirellis. Also, the Pirellis come in the more conservative 45/50 series combination which I was trying to achieve with the Nittos. After looking through all of Nitto's available tire sizes, the only good match I could come up with were the 40/45 series sets I mentioned above. I did some of the tire math and found that each lower-series Nitto as stated above would increase the wheel well gap by a little over 1.5-inches on each. That means, if I install the Eibach springs to lower the front by 1-inch (is that how much it lowers the car?) and lower the height adjustment of the rear air suspension by 1-inch, I've still increased the wheel well gap by a little more that 0.5-inches in each wheel. Not too sure that would look okay. Hmmmm . . .

The whole idea was not only to get the car closer to the road (to lower my CG), but to also enhance the car's appearance by making the car look more "snugly" planted on the road as well. An increased wheel well gap goes counter to that goal. Hmmmm . . .

[sailsmen]

With the Eibach springs and reduced sidewall in the fronts I would be concerned about what effect that would have on bounce and kick back.

Notice the KB goes with a wider front tire to maintain a similar sidewall.

[studio460]

Hmmm . . .

Good point . . . I guess, who knows 'til someone tries it?

Case B: Nitto NT-555s:
Front: . . . . . . . . . Rear:
245/40 ZR18. . . . 255/45 ZR18

Marauder S: Pirelli P-Zeros:
Front: . . . . . . . . . Rear:
255/45 ZR18. . . . 255/50 ZR18

Here, looking side-by-side, it's a bit easier to compare the two specs. Shorter sidewalls in "Case B," true. I would LIKE to emulate the Marauder S set-up. It's just so DARN expensive!

[sailsmen]

It may not be an issue, I would think a good tire person would know how much sidewall flex difference there is between the 2.

I just wanted to point it out.

[MMM2003]

I posted this before, in one of your threads. Here is the link again for the Tire size calculator. http://www.miata.net/garage/tirecalc.html

It's a pretty handy tool and you can compare the overall Diameter to each other by choosing the tire size you want.

Oh, don't be mislead by the Miata link, it's a universal calculator.

[studio460]

Sure, Sailsman, thanks for pointing that out! Didn't mean to sound snippity or anything. Sidewall stability is something I am pretty concerned about. What with the weight of these cars and the punishing cornering I'm planning to put the car through . . .

[looking97233]

NBC- The stock tires.... front 27.3" tall, rear 28.6" tall. Divide the rear by the front to get a ratio of the two. It is 1.05.
This is the important thing to keep in mind (the ABS module will go into fits if you stray to far) other than that you can go with whatever size tires you like. Keep in mind your spedo and odo will be off unless corrected by a chip.
Hope this helps.

[looking97233]

Oh, one more thing...

Figurein' the height of a tire...

width X series X 2 / 25.4 + wheel size= tire height.

Example:
Stock front tire...

235 X 50 X 2 / 25.4 +18= 27.25 round up to 27.3"

[BigMerc]

good info, Hey LOOKING whats the update on the Badges, you got customers all around here.

[looking97233]

ooopppps!

the series should be .50 not 50. Duh, silly me.

[studio460]

Thanks for your informative post, looking97233. Here's the tire diameter (inflated) info taken directly from the Nitto site . . .

Stock BFGs:
Front: . . . . . . . . . . . . . . . . Rear:
235/50 ZR18 27.3". . . . . . .245/55 ZR18 28.6"

Case B: Nitto NT-555s:
Front: . . . . . . . . . . . . . . . . Rear:
245/40 ZR18 25.67" . . . . . 255/45 ZR18 26.97"

The difference between the front/rear Nitto tire diameters, as spec'ed above, is 1.3" according to Nitto.

The stock ratio you pointed out is: 28.6"/27.3"=1.0476
The ratio fo the Nittos above would be: 26.97"/25.67"= 1.0506
Hmmm . . . I think I have a WINNER! A difference of 0.003" Here's the difference in tire height in a table:

Front: . . . . . . . . . . . . . . . . Rear:
27.3" . . . . . . . . . . . . . . . . .28.6"
25.67". . . . . . . . . . . . . . . . 26.97"
-------------------------------------------
(1.63") . . . . . . . . . . . . . . . (1.63")

Also, according to at least one Eibach dealer, the the Eibach front springs (part no. 3596.120) drop the front by 1.1" (and also state, correctly, that the rear drop is "N/A"), but Eibach's own site specs the front drop at 1.4" which I think is wrong since they also spec a rear height drop of 1.2" which is absolutely wrong since there are no springs to replace in the rear.

So, now, I have a 1.63" increase in wheel well gap. And now I need to divide 1.63"/2=0.815." Less a 1.1" drop from the Eibachs in the front, and a manual 1.1" drop with the rear height adjustment, leaves me with an overall wheel well gap decrease of -0.285" compared to stock.

Decrease in overall wheel well gap after Nitto 40/45-series tires and Eibach springs = -0.285"

[studio460]

Oh, I also forgot the most important part . . .

My overall ride height would drop by nearly two whole inches at -1.915"!!!

I CAN'T WAIT 'TIL MY BFGs WEAR OUT!!!

[looking97233]

sounds good, If you like it... do it. Only problem will be the spedo, but you should be able to have Trilogy set the chip up (that will come with your SC, 01.2004) for it.

[studio460]

Okay, maybe I could go even lower. Look at this . . .

Case C: Nitto NT-555s:
Front: . . . . . . . . . . . . . . . . Rear:
265/35 ZR18 25.28" . . . . . P275/40 ZR18 26.61"
Rear-to-front ratio = 1.0526

Wonder if THESE will fit? Otherwise, I could try . . .

Case D: Nitto NT-555s:
Front: . . . . . . . . . . . . . . . . Rear:
255/35 ZR18 25.08" . . . . . P275/40 ZR18 26.61"
Rear-to-front ratio = 1.06100 (+0.011 greater than stock ratio)

[TooManyFords]

We all want to see it dropped 2"!

Put down the babes and get busy! :D

[darebren]

on the stock rims, we should not go beyond 255's, so you will need new rims and 9 or 9.5 inches (all the extra width to the inside), these rims do not exist cheaply as we have all seen.

I think the Pirelli's are the answer...more bucks I know..

[studio460]

TooManyFords . . .

I AM DYING TO GET THOSE NITTOS ON! But I have to wait until the stock BFGs wear out! Also, can't find any dealers with the Eibachs in stock.

Darebren . . .

Yeah, I was wondering about that . . . thanks. I've been thinkin' real hard about Lidio's modded factory rims and the Nitto drag radials. I suppose I could get the widened rims and put the 275/40 555 tires on there instead for extra drivability and longer wear (compared with the 305/45 555R drag radials Lidio's intending for the widened rims).

[Slowpoke]

I am definitely up for a set of new tires in March. Perhaps we can get a good price if enough people go for it. NBC is in California; dont think that will work - but I checked the Nitto website and there is only one dealer in chicago - perhaps we can aproach them.

mean time, i will do my best to wear 'em out before then!