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325’s on the rear for the track?

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So, due to the slim pickings in 315/30/19 I’m thinking about running 325/30’s in the rear for track use. I’m sick of chording Hoosiers so looking at all the other choices but going to have to go bigger just to keep options open. I’m concerned about possible rubbing during hard track driving. I currently have 325/30 PS 4’s on the rear for street use and have had no issues with rubbing.

Has, or is anyone track driving with 325’s on the rear? Any rubbing issues?

Thanks all!
 

Ludachris

Chris
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For those who aren't running a squared set up, I imagine running a staggered setup with 325's in the rear and say 275's or 285's on the front would result in some additional understeer? Asking for a friend 😏 🤦‍♂️ Looks nice on the street but it isn't ideal for the track.
 

Apex Wheels

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For those who aren't running a squared set up, I imagine running a staggered setup with 325's in the rear and say 275's or 285's on the front would result in some additional understeer? Asking for a friend 😏 🤦‍♂️ Looks nice on the street but it isn't ideal for the track.
That's why you pair with with at least 305 up front :)

We have a lot of Mustang and Camaro customers running 325 rear setups on 11.5-12" wide wheels and it works quite nicely. The tire selection is much better compared to 315/30 as you eluded to. A popular selling setup has been 305/30-19 front and 325/30-19 rear NT01s for HPDE use.
 
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For those who aren't running a squared set up, I imagine running a staggered setup with 325's in the rear and say 275's or 285's on the front would result in some additional understeer? Asking for a friend 😏 🤦‍♂️ Looks nice on the street but it isn't ideal for the track.
Well, there's more to it than just the numbers on the sidewalls. I ran last year with 285/35x19 front, 325/30x19 rear Pirelli Trofeo R's. The 285/35's measured as 305/32.7's and handling was surprisingly good.
 

Bill Pemberton

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Having run a staggered system for years on Vipers I have to say from a cost perspective it is not overly advantageous for the wallet. Obviously there are advantages to such a system or we would not see it constantly on many performance machines. That said , I imagine most folks will favor a squared system for the ability to rotate/swap sides extending tire life. If one is desiring to go staggered a 325 should fit as noted, and the choices are out there with tires that should be ( in most cases ) at a lower price than Hoosiers. They should wear a bit longer also and all are available through the TMO link to TireRack. Would suggest , based on cost to the racer , the following three , for a bit more tire wear, yet still pretty damn quick;

1. Goodyear F1 3R
2. Michelin Sport Cup 2
3. Trofeo R

Pretty big price difference from the Goodyear to the Pirelli , and I admit my biases are towards the Michelins and Goodyear.
 
All, thanks for the intel! Looks like I’ll be getting some 325’s for the rear. Still planning on running a staggered setup however. I have a set of Forgeline’s that I use for the track and would be expensive to replace them. 11’s up front and 11.5 in the rear. Thinking about the Goodyear’s in a 305/325 setup. Hopefully they will way outlast the Hoosiers without much loss of grip.
 

Bill Pemberton

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Good luck BadVoodoo and am sure many will look forward to hearing your impression on the Goodyears. Have some friends who had good luck with them , and the TireRack link here shows they are the price leader. Would bet you will only be about a second slower than the Hoosiers, but with the extra width, that could just disappear and they might be equal?
 

boardkat

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you going with NCRC end of the month? I am thinking of going if the weather looks good.
Nope, SFSpeed - it's a bit of a trek for me (9 hours), so I won't be there often, but need this setup/seat time ahead of Optima LVMS next month.
 

boardkat

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The bespoke 315/30-19 GT350R Cup 2 is faster and stickier than the off the shelf 325/30-19 Cup 2.
Any experience with the 2020 version of the 305 or 325 IMSA Michelin or Pirelli soft or medium compound tires? Picked up a Daytona qualifying set of 305 Michelin softs dirt cheap to have some track day fun when I’m not competing on series mandated 200TW tires, and interested to hear how grip and wear compares to other tires.
 
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Bill Pemberton

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Be ready to drive around corners like you have super glue on the tires ----- you will find a completely new level of sticktion!!! Have fun , but I would conservatively guess around 3 seconds a lap quicker , if not more.
 

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