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View Poll Results: What width for the 18" rear would you prefer?
9-10"
7.32%
10.5"
17.07%
11"
24.39%
12"
51.22%
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Drag Pack poll

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Old 10-26-2017, 07:24 PM
  #81  
Mike Jesse
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Originally Posted by FYREANT
Doesn't that only support a top speed of 130 mph?
"Speed ratings are based on laboratory tests where the tire is pressed against a large diameter metal drum to reflect its appropriate load, and run at ever increasing speeds (in 6.2 mph steps in 10 minute increments) until the tire's required speed has been met."

Found this info on Tire Rack about the speed rating.
For short bursts I think we are ok.

I've always used bias ply tires while drag racing. This is new to me.
I do know we should not mix radials with bia plys.

Last edited by Mike Jesse; 10-26-2017 at 07:45 PM.
Old 10-26-2017, 07:28 PM
  #82  
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Originally Posted by Mike Jesse
That looks like it's not seated with the wheel almost.
How much PSI? Bump it to 40 PSI.

I'm going to use the M/T Sportsman S/R size 26x6/18.
thats the way my C7Z repos look with my rear radials currently. Huge wheel lip
Old 10-26-2017, 07:29 PM
  #83  
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Originally Posted by Poppacapp
thats the way my C7Z repos look with my rear radials currently. Huge wheel lip
Which are ET streets btw... so you may still have the same look with a set of MT too
Old 10-26-2017, 07:32 PM
  #84  
blown81bu
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Originally Posted by Poppacapp
thats the way my C7Z repos look with my rear radials currently. Huge wheel lip
so u think its the rim or the tire?
i never seen a repo look like that...pic?
Old 10-26-2017, 08:07 PM
  #85  
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Originally Posted by blown81bu
so u think its the rim or the tire?
i never seen a repo look like that...pic?
Its the rims. I will get a pic of mine when I get home from work tonight and post it up.
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Old 10-26-2017, 09:07 PM
  #86  
robz
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Both tires will work. The m and h are front runners technically should make a better skinny.
The narrower, lighter tire will help performance more in general.
Those 18" m and h front runners are 18 lbs.
Always do a shakedown run and balance the skinnies for safety. I always check the rake also.
Best to have a + rake even if it's only 1/2".
Make sure those rims fit without rubbing during function including turns, hard braking, and even a few bumps.

Last edited by robz; 10-26-2017 at 09:27 PM.
Old 10-26-2017, 09:19 PM
  #87  
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Slicks on back with full size radials on front wander and dart around on the big end especially:
- in the cold/cold track
- when the rears tire pressure is run low
**some people have reported that too high pressure in rear dr can be an issue with stock RF up front.
- when the tire size is smaller and more sidewall
- when speeds are higher
So, it's not worth the risk especially when you don't have a lot of seat time.

Radials out back with bias ply skinny up front is fine in general for most setups we can come up with.

Bias ply tires out back with radial skinny up front will work in alot of situations as well even though not ideal but follow the rules above.

It's always safest to not mix but mixing with have a skinny up front can work in many situations as long as your not doing anything extreme. Always best to do a shakedown run to see how comfortable you are speeding down the track. Everyone has different thresholds.

Last edited by robz; 10-27-2017 at 07:52 AM.
Old 10-26-2017, 09:48 PM
  #88  
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lots of knowledge there Rob Z
Question for u
My best is 140.77 how much will i pick up w the skinnies on My Corvette?
I say 1 mph....hopefully i can pick up some 60 foot time
Old 10-26-2017, 09:54 PM
  #89  
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Originally Posted by robz
Slicks on back with full size radials on front wander and dart around on the big end especially:
- in the cold
- when the rears tire pressure is lower
- when the tire size is smaller and more sidewall
- when speeds are higher
So, it's not worth the risk especially when you don't have a lot of seat time.

Radials out back with bias ply skinny up front is fine in general for most setups we can come up with.

Bias ply tires out back with radial skinny up front will work in alot of situations as well even though not ideal but follow the rules above.

It's always safest to not mix but mixing with have a skinny up front can work in many situations as long as your not doing anything extreme. Always best to do a shakedown run to see how comfortable you are speeding down the track. Everyone has different thresholds.
My current setup until the dragpack comes in is factory front 19x10 285 tires and C7Z 19x12 repos in the rear with MT ET street SS 325/30-19 radials. I can say without a doubt it sucks to drive the car in this config. The rear end moves around way too much. Tramlines and sways bad on the road in road ruts. At the track its hard to keep a solid line.

I guess the huge front wheels are causing all the play with the soft rears. Cant wait toget the full drag pack on the car.
Old 10-26-2017, 10:26 PM
  #90  
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Originally Posted by blown81bu
lots of knowledge there Rob Z
Question for u
My best is 140.77 how much will i pick up w the skinnies on My Corvette?
I say 1 mph....hopefully i can pick up some 60 foot time
A lot depends on setup, type of front runner vs full size tire.
I think it's fair to expect up to .1 and 1-2 mph.
Old 10-26-2017, 10:29 PM
  #91  
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Originally Posted by Poppacapp
My current setup until the dragpack comes in is factory front 19x10 285 tires and C7Z 19x12 repos in the rear with MT ET street SS 325/30-19 radials. I can say without a doubt it sucks to drive the car in this config. The rear end moves around way too much. Tramlines and sways bad on the road in road ruts. At the track its hard to keep a solid line.

I guess the huge front wheels are causing all the play with the soft rears. Cant wait toget the full drag pack on the car.
Yeah no doubt.
When everything is setup right with the drag pack, alignment, and suspension the car will feel like a dream to run on the strip.
Old 10-26-2017, 10:36 PM
  #92  
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So is the rear end all over the place with radials on back and runners up front? Or just when there are regular width tires up front?
Old 10-26-2017, 11:12 PM
  #93  
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Just signed up for my first private track rental. I will be purchasing a set of 18x10.5 TSW Interlagos with 315 30 18 hoosier slicks I'm going to mount on them. I have a base model so 18s in the front already. I was thinking about running nitto invo's in the front as I read stock run flats are not a good pair. Is that correct?
Old 10-27-2017, 07:02 AM
  #94  
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Originally Posted by KKC7
Just signed up for my first private track rental. I will be purchasing a set of 18x10.5 TSW Interlagos with 315 30 18 hoosier slicks I'm going to mount on them. I have a base model so 18s in the front already. I was thinking about running nitto invo's in the front as I read stock run flats are not a good pair. Is that correct?
You should be fine but test it maybe with RF and non RF if possible. The stock runflats up front can work too but people have reported its uncomfortable like you mentioned. A lot will depend on the specific setup. I'll test my setup today to give feedback with stock RF in front.

For all: Might be worth reading up on those threads because there are conflicting opinions on what is causing high speed swaying. Some specific tires just don't mesh with others.
Skinnies will track best.

Always do a test run on track or street if you have to ,to get feel for it and see what's happening.

IMO if you are 500hp or under the 315 is quite big.
I'm testing a 245..

Last edited by robz; 10-27-2017 at 08:02 AM.
Old 10-27-2017, 08:14 AM
  #95  
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Originally Posted by robz
You should be fine but test it maybe with RF and non RF if possible. The stock runflats up front can work too but people have reported its uncomfortable like you mentioned. A lot will depend on the specific setup. I'll test my setup today to give feedback with stock RF in front.

For all: Might be worth reading up on those threads because there are conflicting opinions on what is causing high speed swaying. Some specific tires just don't mesh with others.
Skinnies will track best.

Always do a test run on track or street if you have to ,to get feel for it and see what's happening.

IMO if you are 500hp or under the 315 is quite big.
I'm testing a 245..
That would be great. Let us know. ​​​​​​I was planning on testing them before I switch the fronts when they come in. I'm around 650whp
Old 10-27-2017, 11:24 AM
  #96  
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Originally Posted by FYREANT
So is the rear end all over the place with radials on back and runners up front? Or just when there are regular width tires up front?
Front runners should be fine. The wide factory fronts are so big they cause the rear to sway with slight steering movements.
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Old 10-27-2017, 11:27 AM
  #97  
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Originally Posted by blown81bu
Are the m/t better than these m&h
Notice gap between rim and tire and look flat w weight from car...maybe m/t better?

here is a pic of my C7Z repo 19x12 with the ET street on it.

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Old 10-27-2017, 02:06 PM
  #98  
Mike Jesse
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17 Stingray. Stock fronts aired up to 40 PSIG.
285/40R18 M/T SS drag radial, 25 PSIG.


No issues with running down track.
Very slight rear sway occasionally.
Didn't move the steering wheel, just drove through it.


17 Z06. Stock fronts aired up to 40 PSIG.
Stock rears, 26 PSIG.
Arrow straight every time.
Old 10-27-2017, 06:08 PM
  #99  
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Originally Posted by Poppacapp
here is a pic of my C7Z repo 19x12 with the ET street on it.

not a fan of that lip overhang!
Old 10-27-2017, 06:36 PM
  #100  
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Originally Posted by KKC7
That would be great. Let us know. ​​​​​​I was planning on testing them before I switch the fronts when they come in. I'm around 650whp
2017 GS
18" Hoosier drag radial rears(29psi)
19" stock OEM tire/rim(32psi)
57*

I ran the car up to 95mph 3 times on the street and the car tracked perfectly straight.
I will test again to 120 +mph and post back.


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