370z MEATY TIRE THREAD

[FortuneLSX-TT]

Originally Posted by cjr1881

Yeah those are the only tire options in 20" and they are just fine. I would rather go taller than smaller with performance upgrades I want first gear to be useable. 285/35/20 315/30/20

315*.30= 94.5mm sidewall
20*25.4= 508mm rim
508+94.5+94.5 = 697mm overall diameter (27.44in)

vs stock
275*.35=96.25mm sidewall
19*25.4= 482.6mm rim
482.6+96.25+96.25=675mm overall diameter (26.57in)

You're increasing your rear overall tire diameter by almost an inch.

315*.25= 78.75 mm sidewall
20*25.4 = 508mm rim
508+78.75+ 78.75 = 665.5 mm overall diameter (26.2in)
The 25's drop about .4in from stock whereas the 35's add almost a full inch in those sizes.

If I was going for 20's I'd go with the 25 and not the 30, but good luck. I think first gear will still be usable in either size, but like others have said... much taller than stock. I'd be interested to see how it looks and how far off your speedo is and if you have any rubbing issues etc.

[cjr1881]

Originally Posted by FortuneLSX-TT

315*.30= 94.5mm sidewall
20*25.4= 508mm rim
508+94.5+94.5 = 697mm overall diameter (27.44in)

vs stock
275*.35=96.25mm sidewall
19*25.4= 482.6mm rim
482.6+96.25+96.25=675mm overall diameter (26.57in)

You're increasing your rear overall tire diameter by almost an inch.

315*.25= 78.75 mm sidewall
20*25.4 = 508mm rim
508+78.75+ 78.75 = 665.5 mm overall diameter (26.2in)
The 25's drop about .4in from stock whereas the 35's add almost a full inch in those sizes.

If I was going for 20's I'd go with the 25 and not the 30, but good luck. I think first gear will still be usable in either size, but like others have said... much taller than stock. I'd be interested to see how it looks and how far off your speedo is and if you have any rubbing issues etc.

There is no /25/20. He made a typo, those are the only tires available in 20". I used an offset and tire calculator and it says I will be doing 62 when my speedometer says 60. 2.8% I think it said. I don't have anything to consider because there are only 2 tires made in R888 20" - 315/30 285/35. If anyone knows of any other competition 20" tires I am all ears. I think maybe michelin, but I hate them. Other than that, I don't know of any other tire company that makes 20" competition DOT tires.

[wheee!]

Time for some pics from the Hankook install... 305/30/19 rear and 275/35/19 front

thanks to EVOHUNTER for the great deal and service!

[One_Quick_Z]

LOL at the guy bashing me about my tire choice and then when it comes time for him he does the same thing almost and then trys to justifiy it.









DAN

[Nissanboy]

Originally Posted by cjr1881

You need to keep the total circumference of the tire the same or you will change your gearing. He has effectively shortened his gearing and will now take more rpms to achieve the same speed. The profiles for 19" tires on the 370Z should be front/40/19 rear/35/19. His are F/35/19 R/30/19 . When his speedometer says he is doing 60mph, he will actually be doing about 50mph. 17-18% off. I can't believe how many cars I see with the wrong profile tires. People are obviously oblivious to the fact that they are not just changing how the tire looks. If you plus size you need to change aspects accordingly, and if you keep same wheel size then you must keep same aspect or you will be changing gearing and your speedometer.

17-18%?!??! What are you smoking?
@ 60mphs, his speedometer will be off about 1 1/2 mph, resulting 61-62 mph

Do the math Tire size calculator

[W.O.W. 370Z]

Originally Posted by Ron

wow if you ever decide to change wheels (again) hit me up. I'll buy those.

PM me.

Contemplating changing it up, again.

[Shamu]

I use 315/30/18 rears and 295/30/18 fronts on 18x10.5 and 9.5 wheels. Looking for more wheel.

[Rusty]

Some pic's of my set-up finally. Mich PSS's, 275/35-19, and 325/30-19 on 9.5" and 12" ForgeLine ZX3R.

[Ron]

constructive criticism? Front tire sidewall is a little to tall. And you need a drop! Other than that, sweet setup

[W.O.W. 370Z]

Originally Posted by Ron

constructive criticism? Front tire sidewall is a little to tall. And you need a drop! Other than that, sweet setup

I was thinking same thing but its OD is 25.6. Looks tall in pics.

[Rusty]

Originally Posted by W.O.W. 370Z

I was thinking same thing but its OD is 25.6. Looks tall in pics.

Sorry, wrong tire size for the front. It's 275/35-19. So the OD is 26.6. I wanted to run the same set-up you have. But couldn't get these rims in a 20" diameter size. So I got the 19's instead. I wanted the tire OD to be close to stock with these rims.

[W.O.W. 370Z]

Originally Posted by Rusty

Sorry, wrong tire size for the front. It's 275/35-19. So the OD is 26.6. I wanted to run the same set-up you have. But couldn't get these rims in a 20" diameter size. So I got the 19's instead. I wanted the tire OD to be close to stock with these rims.

Disregard my post.

[Rusty]

Originally Posted by Ron

constructive criticism? Front tire sidewall is a little to tall. And you need a drop! Other than that, sweet setup

The drop may be my winter project. Thinking with Ohlins.

[Ron]

uuuuh deep pockets.

[Rusty]

Originally Posted by Ron

uuuuh deep pockets.

Widower, empty nester about to retire in 6 years. GF makes more money then me.