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Smaller contact patch with higher pressures.
Have you tried shaving your tires or having them shaved? Shaved tires last longer and have a wider contact patch than off-the-shelf tires.



I quote from https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=67
"One of the reasons radial racing slicks are so effective is they feature shallow tread depths, and their contact patch acts as a single unit. However, any tread design that breaks up the contact patch into smaller elements or adds additional tread depth (required to enhance wet traction) will increase tread block squirm and reduce dry performance. This means that tires typically provide their worst wet traction and their best dry performance just before they wear out. It's also important to remember that the heat generated every time a tire is driven activates bonding agents in the rubber. As this process is repeated continually throughout the tire's life, its rubber compounds gradually harden and lose flexibility, reducing the tire's grip. Therefore, a shaved new tire will provide more traction than a tire worn to the exact same tread depth after being driven for thousands of miles on the road. "
 

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That is why the RE will be wearing some PS Cup 2’s with BIGGER new wheels for its spring reveal. Stay tuned; working on four big ones to hold them with Biz. Going to have a good looking functional machine for my addiction. Those Cup 2’s have little or no thread.

I have my new cradle bushings ready to be installed. Going to score the adjustable AAD arms back and front and add a front strut brace, change the front springs then adjust it all up and turn it loose again and see what it will do!
 

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That is why the RE will be wearing some PS Cup 2’s with BIGGER new wheels for its spring reveal. Stay tuned; working on four big ones to hold them with Biz. Going to have a good looking functional machine for my addiction. Those Cup 2’s have little or no thread.

I have my new cradle bushings ready to be installed. Going to score the adjustable AAD arms back and front and add a front strut brace, change the front springs then adjust it all up and turn it loose again and see what it will do!
Nice...
 

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Have you tried shaving your tires or having them shaved? Shaved tires last longer and have a wider contact patch than off-the-shelf tires.



I quote from https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=67
"One of the reasons radial racing slicks are so effective is they feature shallow tread depths, and their contact patch acts as a single unit. However, any tread design that breaks up the contact patch into smaller elements or adds additional tread depth (required to enhance wet traction) will increase tread block squirm and reduce dry performance. This means that tires typically provide their worst wet traction and their best dry performance just before they wear out. It's also important to remember that the heat generated every time a tire is driven activates bonding agents in the rubber. As this process is repeated continually throughout the tire's life, its rubber compounds gradually harden and lose flexibility, reducing the tire's grip. Therefore, a shaved new tire will provide more traction than a tire worn to the exact same tread depth after being driven for thousands of miles on the road. "
No. Because the tires most of us use for track purposes already have so little tread on them anyway.

Example:
PZero 265/35/19 tread depth: 10/32" when new
Trofeo R in same size: 6/32" when new

Shaving has no effect on contact patch size. Only a reduction in squirm.
 

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No. Because the tires most of us use for track purposes already have so little tread on them anyway.

Example:
PZero 265/35/19 tread depth: 10/32" when new
Trofeo R in same size: 6/32" when new

Shaving has no effect on contact patch size. Only a reduction in squirm.
Regarding contact patch size:
The tread sipes are generally not straight 90 degree angle from the tire carcass, they are sort of a truncated pyramid, as it were, with slightly slanted sides, thus, the closer to the carcass they get, the more tread there will be, just as a pyramid has greater CSA near the ground than it does halfway up. Not a LOT of extra contact patch width gain, but some.

Another way to demonstrate this is that the grooves generally get narrower closer to the tire carcass, meaning the sipes are getting wider.
 

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Hello all,

Some updates on my road-course setup. In a few days the cat will have the following installed:

- Mopar rear seat delete (not really a handling mod but helps with weight)

- Mopar Redeye spoiler

- BMR bushings and suspension parts
BMR-TR110R Toe rods, rear, on-car adjustable
BMR-SCB110 Bushing kit, rear cradle ockou
SPF-3048K Bushing kit, front radius rod, non-adjustable, elastomer
SPF-3052K Bushing kit, front lower control arm, inner, non-adjustable

- SPC Upper Control Arm
SPC-66045

- BBK Black Billet Hemi Hellcat Throttle Body 100MM (15-19)

- Front Sway Bar Set from HotchkisSport Suspension (#22121F)

- FI Interchillers Hellcat Blower Spacer Plates (not a handling mod but helps with heat; so I have read)

- Mishimoto intercooler hose kit (not a handling mod but I thought it would be cool :) )
MMHOSE - MOP62-15BK

Can't wait until this is completed.

Then some time soon I will get wider wheels, lil devil fender flares, new pulley, exhaust, 426 CI stroker kit, cam, exhaust and tune.

Will keep everyone posted.
forgot to mention I also have the Diff Brace from P4 going on their as well.
 

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Regarding contact patch size:
The tread sipes are generally not straight 90 degree angle from the tire carcass, they are sort of a truncated pyramid, as it were, with slightly slanted sides, thus, the closer to the carcass they get, the more tread there will be, just as a pyramid has greater CSA near the ground than it does halfway up. Not a LOT of extra contact patch width gain, but some.

Another way to demonstrate this is that the grooves generally get narrower closer to the tire carcass, meaning the sipes are getting wider.
If what you’re saying is true - could be; I’m not disputing it at all....

BUT the additional tread contact would be so minuscule compared to the sum total.... there’s not a driver in this forum that is good enough or consistent enough to detect any benefit from contact patch gained.

Not that it wouldn’t be fun trying!
 

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If what you’re saying is true - could be; I’m not disputing it at all....

BUT the additional tread contact would be so minuscule compared to the sum total.... there’s not a driver in this forum that is good enough or consistent enough to detect any benefit from contact patch gained.

Not that it wouldn’t be fun trying!
I was mainly thinking of an old article dealing with full-depth high-perf tires versus shaving them. The main benefits were less sipe squirm and a little bigger contact patch. on that particular tire, the tread really leaned inwards at the outer circumference, so they gained overall tire contact patch width as well as size.

On Z-rated tires, I think that it would be largely academic, as you pointed out.
 

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That's awesome. Wish I could buy an HC RE and run that wide of a tire. any advice for us narrow body guys who want a square setup and wider tires all around? I found a video once of a guy on a scat pack running 11" square all around with 305s. I would be happy to be able to run that with no spacers and clearance issues.

btw the car looks awesome.
 

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That's awesome. Wish I could buy an HC RE and run that wide of a tire. any advice for us narrow body guys who want a square setup and wider tires all around? I found a video once of a guy on a scat pack running 11" square all around with 305s. I would be happy to be able to run that with no spacers and clearance issues.

btw the car looks awesome.
@TrackDay has a regular body figured out I believe. I don't know if an 11" or 10.5" works up front. He will say.

For starters I have a set of 11" wide 20" Bravados, in the silver color that are the ones for the back. Just pulled them down, cleaned them up, took Biz's wrap and got them ready. I am going to the for sale sections of the Forums for $200 plus shipping. They have drag radials on them with 4/32 at best. But good for a day at the strip or the local burnout contest, before use like you are thinking.

Thanks, for the compliment, these sizes almost look like they were planned by someone at FCA. I am more than happy with the Widebody for fitting wheels/tires. The wheels are absolutely lined up on their vertical center line and top of flairs. This very set-up with this rubber and DP brakes should be a package from them with just a few other well placed changes and the Demon treatment of weight savings plus even a bit more light. Hell they have more than enough power.
 

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Have you tried shaving your tires or having them shaved? Shaved tires last longer and have a wider contact patch than off-the-shelf tires.



I quote from https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=67
"One of the reasons radial racing slicks are so effective is they feature shallow tread depths, and their contact patch acts as a single unit. However, any tread design that breaks up the contact patch into smaller elements or adds additional tread depth (required to enhance wet traction) will increase tread block squirm and reduce dry performance. This means that tires typically provide their worst wet traction and their best dry performance just before they wear out. It's also important to remember that the heat generated every time a tire is driven activates bonding agents in the rubber. As this process is repeated continually throughout the tire's life, its rubber compounds gradually harden and lose flexibility, reducing the tire's grip. Therefore, a shaved new tire will provide more traction than a tire worn to the exact same tread depth after being driven for thousands of miles on the road. "
Street use.
The pavement is shaving my tires for me. Too much, in fact, which is why I dropped rears to 32PSI
 

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Discussion Starter #353
That's awesome. Wish I could buy an HC RE and run that wide of a tire. any advice for us narrow body guys who want a square setup and wider tires all around? I found a video once of a guy on a scat pack running 11" square all around with 305s. I would be happy to be able to run that with no spacers and clearance issues.

btw the car looks awesome.
I'm currently running a 10.5" front wheel with a 10mm offset and a 305/35 R888R mounted. On the rear I run the same tire but with a 11" wheel with a 18mm offset. The fit is tight, especially on the front, but it works well. If I went with a 11" wheel on the front it would for sure stick out past my fender lip.
 

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so guys finally got all those suspension parts installed minus the front bushings. SuperPro said they wouldn't fit but BMRs site said they would. So I exchanged them for a rear sway bar from BMR. Showing the alignment that had to be done for the front control arms.

554542


554543


554544
 

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When are you going to try it?
Once this COVID-19 thing is over I will take her to the track and see how she handles. In the mean time I have been feeling how well she hunkers down on exit ramps. Nothing crazy the highways are not a race course but definitely feels like she is very well planted.

Will be following some of TrackDays advice and going with 20x 10.5's and 305/35's up front. Only difference I like the square setup a lot so be running the same setup on all four corners. But this will come at a later date as I have to limit my spending... so the wife keeps me around :) :p
 

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Once this COVID-19 thing is over I will take her to the track and see how she handles. In the mean time I have been feeling how well she hunkers down on exit ramps. Nothing crazy the highways are not a race course but definitely feels like she is very well planted.

Will be following some of TrackDays advice and going with 20x 10.5's and 305/35's up front. Only difference I like the square setup a lot so be running the same setup on all four corners. But this will come at a later date as I have to limit my spending... so the wife keeps me around :) :p
I used a staggered tire setup on the RE this weekend, and liked it. 345/30R 325/30F.
The rears are hardly tattered! The overall bushing stiffness with adjustable arms and good alignment and custom camber seem to do it good.
The car felt real good, I did not get enough time with it, but I think quicker and harder application of throttle is possible.

My friend with my precious '15 showed up. I think he is thinking of getting some track wheels and tires. How about 305's front like you say, and 315's on the rear with 11's? They may poke, but it could be real functional.
 

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I used a staggered tire setup on the RE this weekend, and liked it. 345/30R 325/30F.
The rears are hardly tattered! The overall bushing stiffness with adjustable arms and good alignment and custom camber seem to do it good.
The car felt real good, I did not get enough time with it, but I think quicker and harder application of throttle is possible.

My friend with my precious '15 showed up. I think he is thinking of getting some track wheels and tires. How about 305's front like you say, and 315's on the rear with 11's? They may poke, but it could be real functional.
Might consider that now that I'm thinking about it.... the poke I think could be fixed with the lil-devils which I have been considering if I went wider all around. it's all money at this point and prioritizing :)
 
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