Anyone running ACR size tires on a non ACR?

[jknappster]

I'm in need of new tires for my 04 and see there are two options for front tires, 275/35-18 (stock size) and 295/30-18 (ACR size). Anyone using the larger of the two? There is only .78" difference in width. Is it worth the extra $. Significant ride feel?

Thanks all.

 

[dtenney]

I believe the ACR sized PS2 tire you are referring to is a Porsche spec tire. I have read that the PS2 sizes for the Viper are a unique PS2 compound for the Viper similar to the Sport Cup compound. If that is correct, than I doubt that you would want to mix tire compounds.

-David

 

[RTTTTed]

New ACR has 19" fronts?

Didn't the 03s get 19" fronts and 20" rears? Like the 10spoke Gen 3 wheels and runcraps that came on my 97 GTS?

Ted

 

[venomous06]

I have the sport cups on my car. Ride is definitely different, tread wear on the PS2 is better than the cups but the cups have way more grip. Cups are a great auto cross tire, were the PS2 leaves a little since they are more the daily driven tires. It's all a toss up as to what you want to do with the car.

 

[venomous06]

New ACR has 19" fronts?

Didn't the 03s get 19" fronts and 20" rears? Like the 10spoke Gen 3 wheels and runcraps that came on my 97 GTS?

Ted

fronts are 18's backs are 19's

 

[dtenney]

I believe the original post was inquiring about the PS2 tire in 295 width that is built for Porsche as an OEM tire? If the question is PS2 vs Sport Cup, the answer is easy, if car is primarily street driven get PS2s, if primarily track driven gets Sport Cups.
-David

 

[RTTTTed]

My 2000 ACR has stock sized 275 x 35 x 18" Kuhmos

My 2001 GTS has 275 x 35 x 18" PS2s

Ted

 

[jknappster]

I should have been more clear. I was inquiring about the PS2 and the gen 4 ACR which is equipped with 295/30-18 on the fronts. Are PS2 really made in different compounds for different sizes?

 

[Viper X]

The difference in the OE PS2 Viper sizes is the C-1 (stiffer) sidewall and a bit less tread depth, which is better for spirited driving.

PS2 tread compound, regardless of sidewall, has a wear rating of 220, so no difference there.

If you are going to run OE PS2 rear tires, you should run OE PS2 front tires as both have the same sidewall stiffness. There is a difference.

If you got to PS Cups, going with the OE ACR sizes is a good idea.

Dan

 

[Leslie]

I run 295's (PS2's) up front on my GenII.

 

[motor602]

what are the pros and cons of running the 295 over the 275 up front??

 

[TommyG]

what are the pros and cons of running the 295 over the 275 up front??

I have heard the pros are reduced understeer and with a more aggressive alignment that adds to this. I have 295 ps2's on a 19 inch front for my street tires.

I just received the 295's in a ps cup for my new 6 spoke snake wheels and will find out how they handle at TWS viper days this month. I have not used my 19 inch fronts on track, only my 04 stock wheels with kumho's and had severe understeer until I got the aggressive alignment done. I still have understeer but not as much on the 275's after alignment.

 

[Leslie]

That was the case for me, I had a lot of understeer (which makes sense with a front heavy car) with the 275's and a lot of push, I was going through front tires twice as fast as my rear tires. The car would drift out on entry point of the turns and would lose grip, so I would have to compensate by turning in tighter, which...of course is not a good thing to do, especially in a high-torque car. Even my tire pressures were higher in the front and I would continually have to keep bringing them down, especially the front driver side if it was a clockwise roadcourse.

Bottom line is, for me I have found the larger I go up front, the more traction I have, less heat build up, less understeer and the tires are lasting longer. I have seen a few track Vipers with 335's all around.

I have heard the pros are reduced understeer and with a more aggressive alignment that adds to this. I have 295 ps2's on a 19 inch front for my street tires.

I just received the 295's in a ps cup for my new 6 spoke snake wheels and will find out how they handle at TWS viper days this month. I have not used my 19 inch fronts on track, only my 04 stock wheels with kumho's and had severe understeer until I got the aggressive alignment done. I still have understeer but not as much on the 275's after alignment.