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I believe our stock rear wheel is 9.5" wide, the minimum recommended size for the 305/35/19 MT drag tire is 10".

Any thoughts, opinions, experience on this?

I'm on the verge of a slew of Timmy upgrades and I'm trying to address my traction issue before more power is added to the car, without purchasing a custom set of rear wheels.
 

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I believe our stock rear wheel is 9.5" wide, the minimum recommended size for the 305/35/19 MT drag tire is 10".

Any thoughts, opinions, experience on this?

I'm on the verge of a slew of Timmy upgrades and I'm trying to address my traction issue before more power is added to the car, without purchasing a custom set of rear wheels.
Don't you already have a set of sweet ass 20" on your ride??
 

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I believe our stock rear wheel is 9.5" wide, the minimum recommended size for the 305/35/19 MT drag tire is 10".

Any thoughts, opinions, experience on this?

I'm on the verge of a slew of Timmy upgrades and I'm trying to address my traction issue before more power is added to the car, without purchasing a custom set of rear wheels.
My $0.02, for what it's worth...

A) Compound matters more than width in regard to traction. I'd understand the wider tires for looks, but not for traction.


B) 305 is, I think, too wide for a 10" rim if you want the car to handle with minimal "slop" entering or exiting a turn. Also, I think the tire size is too wide to run on the stock rim with regard to fender clearance because of the stock rim backspacing.

C) You can fit a 295 on the stock rear, however, but I think that you'll suffer from that "slop" mentioned above. 1MAdSTSV runs his that way. Whats a 1/4" difference in tread width, anyway?

D) Howey Industries site has new front 19x9 and rear 19x10 wheel sets for less than $1599 in the forgestar line for our six-lug rims. If you're putting in a "slew" of upgrades, why not do these too?
 

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On his point A above, the wider you go, will net you more contact patch, but the aspect ratio will decrease, shortening the sidewall. Meaning, for example purposes only, lets say you start off with a stock sized 275/40/19 and want to go wider, but maintain as near close to the stock diameter as possible, so you go 305/35/19. The 275/40/19 has an overall diameter of 86.9" and a 4.3" sidewall. The 305/35/19 has an overall diameter of 86.1" and a sidewall height of 4.2". The shorter the sidewall, the less flexible it is. In this case, you're losing a little bit of sidewall. It's not a lot in this case, but still, these tires don't have a lot of sidewall to begin with.

This IS great for Autocrossing and handling, but for putting down HP/torque from a dead stop, you're just going to blow the tires out from under it as the sidewall doesn't "absorb" that excess torque.

Watch a dragster, be it pro-stock or a nitro car. Note how tall that sidewall is. Now watch it under slow-motion during launch and what that tire does... It "wrinkles". This allows the contact patch to bite the pavement/surface, while the sidewall absorbs the excess torque.
 

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86 in diameter?? Doesn't sound right.my math says tire is 4.2 on tall which would make the wheel tire combo 20 + 8.4. Or 28.4 in overall height
 

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What size tire would you run up front on a 19" wheel?
19's are crazy expensive when compared to 20's (tires) so I never really considered it.
 

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86 in diameter?? Doesn't sound right.my math says tire is 4.2 on tall which would make the wheel tire combo 20 + 8.4. Or 28.4 in overall height
Sorry, I grabbed the circumference column.

Diameter/overall height is 27.7" and 27.4" respectively. I'm using OEM 19" wheels in my calc, not aftermarket 20's. That would make up our 1" difference.
 

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Discussion Starter #8
PORGUY said:
Don't you already have a set of sweet ass 20" on your ride??
Yes, but I need a set of drag radials and would like to use the factory 19. Thank for the compliment.

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Rboughne1 said:
My $0.02, for what it's worth... A) Compound matters more than width in regard to traction. I'd understand the wider tires for looks, but not for traction. B) 305 is, I think, too wide for a 10" rim if you want the car to handle with minimal "slop" entering or exiting a turn. Also, I think the tire size is too wide to run on the stock rim with regard to fender clearance because of the stock rim backspacing. C) You can fit a 295 on the stock rear, however, but I think that you'll suffer from that "slop" mentioned above. 1MAdSTSV runs his that way. Whats a 1/4" difference in tread width, anyway? D) Howey Industries site has new front 19x9 and rear 19x10 wheel sets for less than $1599 in the forgestar line for our six-lug rims. If you're putting in a "slew" of upgrades, why not do these too?
For track days I would keep my daily set up of 20s and super sports. Those tires don't slide to the side for what I do but I need more grip for launches.

If I buy another rim it probably would be a a 20 or what ever size that has a lot of drags sizes available.

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CMNTMXR57 said:
On his point A above, the wider you go, will net you more contact patch, but the aspect ratio will decrease, shortening the sidewall. Meaning, for example purposes only, lets say you start off with a stock sized 275/40/19 and want to go wider, but maintain as near close to the stock diameter as possible, so you go 305/35/19. The 275/40/19 has an overall diameter of 86.9" and a 4.3" sidewall. The 305/35/19 has an overall diameter of 86.1" and a sidewall height of 4.2". The shorter the sidewall, the less flexible it is. In this case, you're losing a little bit of sidewall. It's not a lot in this case, but still, these tires don't have a lot of sidewall to begin with. This IS great for Autocrossing and handling, but for putting down HP/torque from a dead stop, you're just going to blow the tires out from under it as the sidewall doesn't "absorb" that excess torque. Watch a dragster, be it pro-stock or a nitro car. Note how tall that sidewall is. Now watch it under slow-motion during launch and what that tire does... It "wrinkles". This allows the contact patch to bite the pavement/surface, while the sidewall absorbs the excess torque.
I'm tracking so what size drag radial would you recommend?

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06 STS Rob said:
What size tire would you run up front on a 19" wheel? 19's are crazy expensive when compared to 20's (tires) so I never really considered it.
In that configuration the stock 18.

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For clarity, I'm looking 2 place drags on the rear for drag use only. Drag sizes are limited, the 19" that I found was a 305 which made me post this thread.
 

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If you make the car hook hard be ready to fix the rearend. And all you need is a softer street tire I cut 1.78 60 ft times on street tires. I run a 305/35/19 on my Ctsv and its two wide for the rim handles like shit. At 80 and passing cars on the highway it feels like your on ice. 305/35/19 on stock Stsv rim will not work on our car. 295/30/19 realy doesent even work well but you can get away with it.
 

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Discussion Starter #10
If you make the car hook hard be ready to fix the rearend. And all you need is a softer street tire I cut 1.78 60 ft times on street tires. I run a 305/35/19 on my Ctsv and its two wide for the rim handles like shit. At 80 and passing cars on the highway it feels like your on ice. 305/35/19 on stock Stsv rim will not work on our car. 295/30/19 realy doesent even work well but you can get away with it.
Right now I have Super Sports, what tires are softer?

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On his point A above, the wider you go, will net you more contact patch, but the aspect ratio will decrease, shortening the sidewall. Meaning, for example purposes only, lets say you start off with a stock sized 275/40/19 and want to go wider, but maintain as near close to the stock diameter as possible, so you go 305/35/19. The 275/40/19 has an overall diameter of 86.9" and a 4.3" sidewall. The 305/35/19 has an overall diameter of 86.1" and a sidewall height of 4.2". The shorter the sidewall, the less flexible it is. In this case, you're losing a little bit of sidewall. It's not a lot in this case, but still, these tires don't have a lot of sidewall to begin with.

This IS great for Autocrossing and handling, but for putting down HP/torque from a dead stop, you're just going to blow the tires out from under it as the sidewall doesn't "absorb" that excess torque.

Watch a dragster, be it pro-stock or a nitro car. Note how tall that sidewall is. Now watch it under slow-motion during launch and what that tire does... It "wrinkles". This allows the contact patch to bite the pavement/surface, while the sidewall absorbs the excess torque.
So are you saying a 18" will be a better choice?
 
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