The rears must rotate at a faster rate in order for any torque to transfer to the front. If the fronts are rotating faster than the rears than they are basically providing driveline drag through the VC to the gearbox.

 

I'm taking the 19" plunge as well.

What's a good tire size for the best performance and ride?

Also what is the reason for the 19" wheel "performance decrease"? Is it simply an unsprung mass issue or suspension geometry?

Whats the "accepted" size that works and wont toast your diff?


235/40/19
305/30/19

?

 

I just installed 245/35/19's & 305/30/19's PS2 Michelin Pilot Sport's. This car rides and handles better than it did on the original 18's. There is a little neg camber and on the HRE 542R's which has a lot of positive offset and on lowered H&R springs I had to do some trimming on the front plastic inner fender wells which was easy with a good sharp utility knife (just look for the scuff). I wouldn't go back to those rough riding 315/25/19's for NOTHING!!!

There is a .5 difference in size between the front & rears which is .1 more than the factory. The revolutions per mile is 19 difference which is also inside the 21 max Porsche spec. The only problem you MAY encounter is the rear tires are taller than the fronts. Some posters seem to feel that this is/may be an issue. I have enough power on tap that when the rears break loose... it's in a BIG way! This is not an issue for me as my AWD works just fine.

 

235 35 19 305 30 19 is the official size.
i always advise 245 35 19 and 305 30 19.


absolutely no diff issues whatsoever. zip. 0. nada.

 

Wow that's great to hear!

My car's been laid up with a cracked wheel for the last week...I didnt want to spend $6k and wait 8 weeks for BBS/HRE, but I really didnt want to roll ebay OEMs. If I had the time, the forgestar F14 18" were mine choice.

Pretty much the only available thing right away were 18" victor equipments, 36lb Avant Garde Ruger Mesh.

I ran across a set of forgestar 19" and saw this thread, so I snapped them up.

My car is 600HP will there be less tire contact patch now? will the car lose traction easily?

Steve K, you have no issues with the 245 front as well? thats out of the porsche spec correct?

 

absolutely no problem whatsoever.
245 35 19 is what porsche puts on the gt2/gt3/
absolutely fine.
a 245 35 19 is actually a better fit than a 235 35 19 when mated to a 305 30 19.

 

Awesome Steve Thx!

Well, I'm pretty excited to get these wheels on. It certainly sounds like it should increase my car's performance - 245 up front will certainly help dial out the little understeer my setup has.

I dont get it - why do so many hate on the 19" setup? Is it how heavy 19" wheels were? (15 years ago?)

Rep to you Sir!

 

I had 225/40/19 and 305/30/19 without any problems but now I have 225/40/19 and 295/30/19 and better yet the car's handling is better than previous combo.

 

Having a little extra ground/spoiler clearance is also a + !!!

 

You know we need pics of the new wheel/tire combo! Else it didn't happen!

 

Sorry to bump an old thread but it seems no one looking for 19" tires considers this. I am looking to buy right now and it seems most people are running taller rear tires... This is the WRONG way to do things, correct? Seems to me 225/40 and 295/30 (26.1" F / 26" R) would be best. Right??

 

[QUOTE=DNugget991GT3;3791988]235 35 19 305 30 19 是官方尺寸。
我总是建议 245 35 19 和 305 30 19。


绝对没有任何差异问题。压缩。0.nada.[/QUOTE
]

 

That is my understanding as well. I have been searching for tires for some time...My current tires are the PS2 235/35/19 & 315/25/19...obviously these are no longer available in the US. I'm also in Boulder...let me know what you decide to do.

 

The 26 inch tall front could be tough to fit.