I was looking at getting Rota p45 so so so hot, anyway. They recomend on suby dude a 275/295 combo, i would also consider a 255/285. or anything down to 245/275. I am concerned with out right handling. I autocross frequently. I just want to know why would i not go for the massive tires. Other than price. And a slight loss in corner exit speed. The car is allready very fast. And straight lines bore me. Would the diffrence going to the big boys be that big......thanks alot.. also if it helps i was going to drop in tokico d-specs, and i have hotchkis sways.

 

Putting anything on your car that reduces corner exit speed means what you did was bad for handling. The whole point of improving the handling of your car is to increase corner exit speed.

I think your first few dollars should be spent on this:

The Race and High Performance Tire

 

Well i only assume it will give me a slight loss, i dont know for sure, i ment i wont use my power to exit. I was thinking so much more tire would make the speed throught the whole corners faster......Also i just want to get peoples opinions and why they would use what they say. Or if anyone has a reason why bigger is not better. I gotta say recomending that i order a book, wait for shipping, then read it all. (for a simple tire size question) is pretty useless to me, i just want some imput. This forum is here so you can get advise, or information. IF everytime someone asked a question you just recomend they go out and buy a book. No one would be on this thing. we would be at the library.

 

I mean i appreciate your attempt, i really do, i was a bit harsh. but i dont want to go out and buy a book let along one thats nearly 300 pages. i get asssigned enought books as it is. I dont need another. Can someone offer me something besides a reading assignment.

 

The issue with big wheels and tires is weight and MOI (moment of inertia). Increasing the weight of your wheel and tire package and moving that weigh out further from the hub center is bad. It takes more energy to accelerate, turn, and decelerate that wheel and tire mass.

That being said, the OEM wheel and tire package on my '06 weighs 54 to 55 lbs. I and a customer of mine will be purchasing some Kodiak 18 x 10.5" wide wheels that will come in at about 18 lbs each. These wheels along with a set of Kumho 285/30-18 V710s should weigh around 42 lbs total. In this example, going bigger means less weight and a lower MOI. The car should accelerate, turn, and brake noticeably faster.

Another thing to keep in mind, tire compound has more of an affect on grip then tire width. A 225/30-18 Kumho V710 or Hoosier A3S06 will grip better then any 295/30-18 treadwear 140 or higher street tire.

 

Agree.

These tires are for the street and autocross? If so then they will be a compromise. Since you autocross, you know that lap time is the result of

technique
Type of tires
tire size

In other words a 255mm performance tire (such as the Goodyear Eagle F1) is a better choice than a 295 junk tire. I recommend that you shop for a street-autocross performance tire. The size is secondary.

 

I was going to run bfg gforce ta kd;s best dry cornering tire i have em on my shelby cobra and they hold, and break out almost like an R compound, id go R compounds but the tread wear is too much for my wallet. THe wheels im getting at 18x9.5 all 4 they weight 22 pounds rota p45, im willing to take a power loss, for corner grip, and brakes are stronger than the tires right now so even if its more weight the contact patch will be bigger, i think braking will be much better. How about initial turn in responce will a 275 up front be bad or livable.

 

I can agree to that 200%. I have a 275 ****ty tire (which im gonna upgrade as soon as its shot (and its taking a long time...)). I can loose grip on turns easier than i could with even my ****enzas (which actually have decent lateral grip). However, with the full weight of the car going forward, the 275s have much more grip. A nice 255 tire such as Eagle F1 or my choice, KDW NT2, would give you far more grip than a crappy 275 tire. Next time i get tires, im getting 245 F/265 R for better neutral grip, as well as much increased lateral grip. Im tryna work out what kind of suspension to get too, as that also matters.

 

One thing you could look at is this article on Sport Compact Car about 275s all the way around on a 350Z. http://www.sportcompactcarweb.com/pr...n_350z_part_2/

With the p45 you could go 275/35 F ~ 275/40 R and get the car balanced while not upsetting VDC/TCS

You could also save up and get 4 rear nismos and save 4lbs a corner.

Chris

 

I dont havre the $ and cant budget to save up for them, i never use tcs, its off seconds after i turn the motor on. I want to run slightly bigger in the back, i just dont want to have any rubbing when i lower the car 1 inch