stupid question but can you further explain this a little bit more, just so i can get a full understanding; im a rookie when it comes to these things. Is there certain tires you would recommend me buying since these ones have about 1-2 seasons left.

Oh this is awkward too but I used to have your car as my wallpaper for the longest time haha

 

What size tires were on your old wheels?

 

You should re-calibrate the rotary coupling after putting new wheels on. That should take care of it.

 

the tires were 215/55/17


you mean balance the wheels?

 

haha, thanks... as far as rotational mass goes, the closer to the center the better, the further out you push it the more the weight is gonna be a factor. example: wheels of equal weight and width, the one w/the smaller diameter will spin faster w/less force. that's why drag wheels are so small(diameter wise). the reason the the forged 19's are better over all is they're wider and "lighter." you can offset the affect of the larger diameter w/shorter final drive gearing and a light weight 1pc driveshaft.

 

^Thats what i said! 3.5vlsd will fix it.

 

Thanks for the info and tip. As far as what Im experiencing this is all normal than i suppose?

To be honest when you mentioned that, I had no clue what your talking about haha I will have to do further research on this 3.5vlsd to fully understand the purpose and etc.

 

The overall diameter of your current tire is greater then your previous set, which also factors into the car feeling slower.

Final Drive gearing: https://g35driver.com/forums/drivetr...tial-swap.html

 

Its the rear end differential from a manual g35 coupe/sedan or 350z. If you have an automatic transmission this mod will help you feel like you have more power, and give better acceleration. However you may experience a lower mpg from this mod as well, it will cause you to run at a higher rpm in the same gear than the stock 3.3 open diff.

I have a 3.5 vlsd and i really love it!

 

Thanks for the help! Im going to need this DIY thread if im going to tackle this project


I have an 03 G sedan doggy door, would it matter what year the rear end differential came from? (manual g35 coupe/sedan or 350z)

 

Also to note, if your total tire circumference is larger than the prior tire, your speedo is off. On tirerack's website you can find the dimensions of each tire and the revolutions per mile. I had the stock 17s on my car and put a lower profile tire on it. The tire was smaller and was 'faster' than the stock tires. My speedo and mileage was off. The car was 'fast though'. It was easy to hit 80 or 100 on the highway. Cause I was really going 8-10 mph slower as the speedo was reading fast. I verified with 2 different gps units. Now that you're on 19s the tires are probably larger and the 'slower' than your stockers. Check your speedo vs a gps to see just how fast you're really going. I've managed to get really close to the stock tire size on my 19s now the speed is just 1-2 mph fast. Surprisingly that seems normal and acceptable for our speedos. but that's a whole different thread already covered.
changing your rear gears is a big decision and will affect your car a lot. Its not an easy or cheap swap. don't give up on the coupe wheels, they are a great product. refinish and re-tire if necessary. Best of luck.

 

^^thanks for the help much appreciated, makes a lot of sense now that you have explained it like this.

Has anyone used 225/40/19 and 245/40/19 kumho ecsta spt tires? Anyone felt like their pretty loud when driving over a certain speed?

 

I had that model in a 17 size it was ok but a lot different than the oem Michelin. I recommend the tirerack site and reading the the 1000+ reviews there over one or two here in this forum.

 

Were they noisy for you when driving? your experience my differ since my tires have different specs.

 

Yes, others have noticed the same thing. Just the same I'd keep the 19s because they're light, strong, and look great.