Mismatched Tires?

Discussion in 'SRT Hellcat Wheels and Tires' started by rollieman, May 18, 2016.

  1. rollieman

    rollieman Silver Member

    Joined:
    Aug 17, 2015
    Messages:
    267
    Likes Received:
    48
    Trophy Points:
    138
    Vehicle:
    Challenger SRT Hellcat
    Do you see any problem running factory Pirelli 275/40/20 "all season" tires in the front with Pirelli 285/40/20 "summer tires" in the back?

    I know this may not be optimum for handling, but I only drive the car casually with an occasionally 1/4 mile straight line burst on the highway and not into flying around corners.

    I wanted to go up one size in the rear to slightly fill the wheel well a bit better and still retain the factory look,
    (the 285's are about .28" taller and .88 wider than the 275 AS tires.

    Note: will be using the factory wheels.

    Thank you !
     
  2. MABBRYFL30

    MABBRYFL30 NYS President Hellcat Car Club Gold Supporting Member

    Top Poster Of Month

    Joined:
    Feb 10, 2016
    Messages:
    4,609
    Likes Received:
    1,833
    Trophy Points:
    568
    Vehicle:
    Challenger SRT Hellcat
    Tire God is a member of this site along with rboyal. Those guys really know their stuff. Topcat is another good source. Check some of thier threads or posts. This forum is full of many members who help you do your homework. A lot of the Guys and girls really help us. Hellcat brotherhood and sisterhood is a growing network that is unbelievable
     
    • Agree Agree x 2
    • Like Like x 1
  3. 1949chopper

    1949chopper NC STATE PRESIDENT Hellcat Car Club HCC Charter Member

    Joined:
    Oct 5, 2014
    Messages:
    1,254
    Likes Received:
    574
    Trophy Points:
    563
    Location:
    Gold Hill NC
    Vehicle:
    Challenger SRT Hellcat
    You're all set. I run 305s with no problems
     
  4. TNCHARGER

    TNCHARGER SRT Hellcat Supporter Gold Supporting Member

    Joined:
    Nov 19, 2015
    Messages:
    1,001
    Likes Received:
    360
    Trophy Points:
    258
    Vehicle:
    Challenger SRT Hellcat
    For the street I run 275/40 (front) and 295/40 (rear) on both my HC and SRT Challengers. I have run this combo for years on other SRTs I have owned. The 295/40 is 29.2" tall. I have not had any issues on any of the vehicles and it gives the "old school" rake I like. Many others around the forums run this same combo....So yes, the 285 will work fine.
     
    • Like Like x 1
  5. BrakeFade

    BrakeFade Hellcat Member

    Joined:
    Oct 20, 2015
    Messages:
    85
    Likes Received:
    19
    Trophy Points:
    8
    Vehicle:
    Charger SRT 392
    Staggered fitments are perfectly fine as long as they're matched in pairs front or back.
     
    • Like Like x 1
  6. ciphros

    ciphros Gold Member

    Joined:
    Mar 13, 2016
    Messages:
    618
    Likes Received:
    305
    Trophy Points:
    433
    Vehicle:
    Charger SRT Hellcat
    I think the question was around using all season fronnt with summer rear. Understeer would be more prominent, but if you are aware of that, and are after straight line traction, should be fine.
     
    • Like Like x 1
    • Agree Agree x 1
  7. BrakeFade

    BrakeFade Hellcat Member

    Joined:
    Oct 20, 2015
    Messages:
    85
    Likes Received:
    19
    Trophy Points:
    8
    Vehicle:
    Charger SRT 392
    Yeah, I guess I should've been more clear. As long as you use the same tires in the front and same tires in the rear, you'll be fine.
     
    Last edited: May 18, 2016
    • Agree Agree x 1
  8. LIME392

    LIME392 Hellcat Member

    Joined:
    Apr 28, 2015
    Messages:
    61
    Likes Received:
    23
    Trophy Points:
    8
    Vehicle:
    Challenger SRT 392
    I've got the all season PZero Neros on the front with the summerP Zeros out back and I haven't noticed any problems at all.
     
  9. rollieman

    rollieman Silver Member

    Joined:
    Aug 17, 2015
    Messages:
    267
    Likes Received:
    48
    Trophy Points:
    138
    Vehicle:
    Challenger SRT Hellcat
    I was leaning very strongly in that direction (295/40/20) because I agree it gives the car a true "old school" rake which I like and fills the wheel well nicely. IMO the 275/40/20 looks a bit lost in the rear well but looks fine in the front; however, in the end I decided to go with the 285/40/20.

    Interestingly the 295/40/20 goes for $345.00 at Summit whereas the smaller 285/40/20 is $543.97 ????

    By the way thank you ALL for your help !!
     
  10. 4510

    4510 SRT Hellcat Supporter Gold Supporting Member

    Joined:
    May 13, 2015
    Messages:
    722
    Likes Received:
    158
    Trophy Points:
    153
    Location:
    Arizona
    Vehicle:
    Challenger SRT Hellcat
    When you guys went to the taller tires did you get the speedo adjusted at the dealership? Also no problems with the traction control seeing a difference in the rotational speeds of the front and rear tires?
     
  11. TNCHARGER

    TNCHARGER SRT Hellcat Supporter Gold Supporting Member

    Joined:
    Nov 19, 2015
    Messages:
    1,001
    Likes Received:
    360
    Trophy Points:
    258
    Vehicle:
    Challenger SRT Hellcat
    You are thinking old school when there were gears and cable...all electronic now and self adjusts for any size tire. Traction/stability control is no issue as long as there is not more than a 5% variance if I remember correctly.
     
  12. 4510

    4510 SRT Hellcat Supporter Gold Supporting Member

    Joined:
    May 13, 2015
    Messages:
    722
    Likes Received:
    158
    Trophy Points:
    153
    Location:
    Arizona
    Vehicle:
    Challenger SRT Hellcat
    Oh I get the electronics EXCEPT... the auto adjustment.
    I can't speak to the Hellcat... but my 13 Camaro I had to have the speedo adjusted in the tune when I changed the gears.
    Same thing with my Mercury Marauder some years back. An electronic adjustment but an adjustment nonethe less.
     
  13. TNCHARGER

    TNCHARGER SRT Hellcat Supporter Gold Supporting Member

    Joined:
    Nov 19, 2015
    Messages:
    1,001
    Likes Received:
    360
    Trophy Points:
    258
    Vehicle:
    Challenger SRT Hellcat
    I guess I should have said today's electronics...My 2013 SRT had to have the TCM flashed when I changed rear gears but self adjusted for the tires....My HC did not require a flash for the 3.09 gear change..
     
  14. Racist Cat

    Racist Cat Silver Member

    Joined:
    Jan 28, 2016
    Messages:
    1,098
    Likes Received:
    379
    Trophy Points:
    138
    Vehicle:
    Challenger SRT Hellcat
    Depends where the speed signal is picked up. At the Trans, at the differential, or at the wheels.

    My experience coming from the 3509 Ram trucks is, Trans, and gear changes do not effect speedo readings because the speed sensor is located either on the top of the differential, reading ring gear speed, or at the where with the abs sensor.

    Some manufacturers still read off the Trans. Those vehicles will need recalibrated with a ring and pinion change.

    My bet is that Dodge followed their old ways and reads speed at the wheels or at the differential.
     
  15. Tire God 2.0

    Tire God 2.0 Senior Hellcat Member

    Joined:
    Apr 24, 2016
    Messages:
    317
    Likes Received:
    75
    Trophy Points:
    58
    Vehicle:
    Challenger SRT Hellcat
    This is interesting. I would like to know more about the wheel speed sensors and how they recalibrate themselves on the HC. I have always told customers to go to the dealership to get it recalibrated, depending on the vehicle some say they can some say they cant. I have never heard of a vehicle self calibration. For example a vehicle with an indirect TPMS system uses the wheel speed sensors to determine if a tire is going low rather than a sensor in the wheel measuring the pressure and sending the information. If one tire is losing pressure, it will spin at a different RPM and it kicks on the tpms light. But the downside is that if they all go low at the same rate over time because the person doesn't regularly adjust the air pressure like they are supposed to, it won't turn the light on because they are all spinning the same speed because they are all equally low. In terms past, I have had vehicles like this that the customer can only buy two tires right now, and when they have two new tires and two bald tires they are different circumstances and it will trick the car into thing it has a flat tire, so the light stays on until they buy two more tires.
    Another example, I had a guy with a Bentley Continental buy two tires (needed 4 but didn't have money I guess) and refused to put on the same Bently tire, he wanted the cheapest tire in that size. We informed him of the potential issue with his AWD drive train and the traction stability control and any other electronic that might be affected. So we put them on and he came back 15 min later and showed us that the car had limited him to 50mph and said there is potential drive train damage and to go to Bently asap.

    The point is that from what I understand when changing tire diameters and such, the value has to be programmed for the car to understand it. If the HC truly can self calibrate, please provide any links or any info because this is cool. Thanks!
     

Share This Page