Swaped from 28" 315/40 18 Nitto NT05R to 25.5" 315/30 18 Hoosiers

[SUX2BU]

1/25/12
Swapped my 315/40 18 Nitto NT05R drag radials for some 315/30 18 Hoosier drag radials. I'm of the opposite opinion of most of the people on this site when it comes to sticky tires. Most want to run a 305/45 18 tire that is almost 29" tall. I think our cars are too heavy and don't have enough gear to lug such a tall tire out of the hole and down the track. Even on my 28" NT05Rs, I felt, were too tall. I got a smoking deal on 25.4" Hoosier drag radials so i swapped out.

To put it in perspective going from a 305/45 18 to a 315/30 18 is the equivalent of going from stock 3.45 gears to 3.90 gears. Plus all the rotational mass you are getting rid of doesn't hurt.

1/4 mile tracks are closed right now but I will post results as soon as they open. This is the ONLY change I have done since my last trip to the track which resulted in 12.35 @ 112.9 w/ 1.89 60' (12.16 @ 114.7 corrected for +1,429 DA).

Total cost of today's mods: I actually made $25!
Hoosier 315/30 18 drag radials: $375
Sold my 315/40 i8 Nitto NT05R drag radials $400

[Cal 20112SS]

That's a good lookin tire. I love the look of the white lettering. Is that a DOT approved DR? What are you running up front?

[SGOS252382]

If you get the tire to hook well, it should shave some time due to the increased gearing.
And you are correct about the wheel/tire setup being easier to spin down the track. The only issue might be traction with the lower profile tires (but those super sticky tires -basically slicks should get the job done).

Traditionally, you want more side wall (tire flex) when it comes to drag racing.

Ever since getting my converter (3200), my 20" drag radials 305/35/20 just don't cut it. My car makes too much torque leaving the line and just wants to light up the tires. I definitely need a tire with more sidewall. I'm thinking of dropping down to 305/45/18s to get more grip.
I should be pulling 1.6x sec 60' with my setup, but my tires just won't hold the track.

But I think your reason is valid. Your car should definitely run faster if you get a good hook. If you were running different tires (with less grip), you'd be in trouble.

[SUX2BU]

Originally Posted by Cal 20112SS

That's a good lookin tire. I love the look of the white lettering. Is that a DOT approved DR? What are you running up front?

I think all DR are DOT approved.

Originally Posted by SGOS252382

If you get the tire to hook well, it should shave some time due to the increased gearing.
And you are correct about the wheel/tire setup being easier to spin down the track. The only issue might be traction with the lower profile tires (but those super sticky tires -basically slicks should get the job done).

Traditionally, you want more side wall (tire flex) when it comes to drag racing.

Ever since getting my converter (3200), my 20" drag radials 305/35/20 just don't cut it. My car makes too much torque leaving the line and just wants to light up the tires. I definitely need a tire with more sidewall. I'm thinking of dropping down to 305/45/18s to get more grip.
I should be pulling 1.6x sec 60' with my setup, but my tires just won't hold the track.

But I think your reason is valid. Your car should definitely run faster if you get a good hook. If you were running different tires (with less grip), you'd be in trouble.

Are you on NT555R or Mickey Thompsons? If you are on the Nittos that might be part of the problem. The NT555R are probably the only drag radial that has decent enough wear to daily drive but on the flip side it's also at the bottom of the list, performance wise, of all the drag radials.

[SGOS252382]

Originally Posted by SUX2BU

I think all DR are DOT approved.

Are you on NT555R or Mickey Thompsons? If you are on the Nittos that might be part of the problem. The NT555R are probably the only drag radial that has decent enough wear to daily drive but on the flip side it's also at the bottom of the list, performance wise, of all the drag radials.

Yes, I had considered getting some of the very expensive 305/35/20 MT but they don't work for daily driving.

If I was going to run MT, I would get a set of 18" wheels just for drag racing and swap wheels when I go to the track. But I'm very lazy and don't want to change wheels before and after going to the track.

Padre was also pulling 1.6x with his 305/45/18 NT555Rs (bolt ons). The 18" tires with the increased sidewall just have more grip vs 20" in the same tires.

I'm most likely going to drop down to 18" Nurburgrings to match my 20" and run the 305/35/18 NT555Rs out back.
I feel pretty confident I can get down in the 1.6x range with that setup. I think that will be about as good as it gets (60' time wise) for a full weight bolt ons L99 A6.
It would most likely take skinnies and 17" wheels to beat 1.6x sec 60' in an bolt ons L99.
But like I said, that's way too much work for me. I'm into driving to the track and then drivng home.

[SUX2BU]

Originally Posted by SGOS252382

Yes, I had considered getting some of the very expensive 305/35/20 MT but they don't work for daily driving.

If I was going to run MT, I would get a set of 18" wheels just for drag racing and swap wheels when I go to the track. But I'm very lazy and don't want to change wheels before and after going to the track.

Padre was also pulling 1.6x with his 305/45/18 NT555Rs (bolt ons). The 18" tires with the increased sidewall just have more grip vs 20" in the same tires.

I'm most likely going to drop down to 18" Nurburgrings to match my 20" and run the 305/35/18 NT555Rs out back.
I feel pretty confident I can get down in the 1.6x range with that setup. I think that will be about as good as it gets (60' time wise) for a full weight bolt ons L99 A6.
It would most likely take skinnies and 17" wheels to beat 1.6x sec 60' in an bolt ons L99.
But like I said, that's way too much work for me. I'm into driving to the track and then drivng home.

Yeah I had the same idea at first, then I figured I would be driving my car wayyyyyy too much to roll on DR all the time so I bought a second set of 18x11. Then I decided to get every last millisecond out of my car so I got some 18x4 skinnies. I should have known.

You can drive to the track fine on almost any tire. I swap to my track set up the morning of or even the day before and just roll out. I LOL at guys who drive to the track, swap to drag radials and the swap back to regular street tires to drive home. I could understand swapping to slicks at the track but DR, come on. Even on my really soft NT05Rs (and skinnies up front) I would still drive around a few days after the track just running errands cause I was too lazy to swap back.

Hell, on my DD 98 SS i used to have I would do the same thing except I had 28x10 15" MT slicks.

[SGOS252382]

Originally Posted by SUX2BU

Yeah I had the same idea at first, then I figured I would be driving my car wayyyyyy too much to roll on DR all the time so I bought a second set of 18x11. Then I decided to get every last millisecond out of my car so I got some 18x4 skinnies. I should have known.

You can drive to the track fine on almost any tire. I swap to my track set up the morning of or even the day before and just roll out. I LOL at guys who drive to the track, swap to drag radials and the swap back to regular street tires to drive home. I could understand swapping to slicks at the track but DR, come on. Even on my really soft NT05Rs (and skinnies up front) I would still drive around a few days after the track just running errands cause I was too lazy to swap back.

Hell, on my DD 98 SS i used to have I would do the same thing except I had 28x10 15" MT slicks.

Cool. I can't wait to see how your car runs. We've been having a lot of track events down here and the weather's been real warm for this time of year. I think it got up close to 80 today.
I'm hoping to get a good track day before the winter's over. Down here its really hard to get a cool weekend day when the track is open for Test and Tune. It seems like whenever there's a good weather day, the track is having a big event and there's no test and tune.
But there's a couple days coming up in February. I just hope there's some decent weather.
Once March arrives it starts getting pretty warm (basically 80s everyday) in my area and the chance of running fast times is pretty much gone.

I think my car has a 12.0 @ 114 mph in it if the conditions are real good (temps in the 50s). But its really hard to get a day that cool when the track is open down here.

Good Luck

[RED BARON]

Any updates on this setup?

[ChargedCamaro]

How are the new tires? Have you tried hooking up in them yet?

[SUX2BU]

Originally Posted by ChargedCamaro

How are the new tires? Have you tried hooking up in them yet?

They hooked up a little too well!

http://www.camaro5.com/forums/showthread.php?t=205498

[ChargedCamaro]

Wow, what RWHP are you putting down? There must have been no spint at all!!!

There is a set of Hoosier racing slicks 295/675R18 GT for sale locally that I might pick up. Think they are any good?

[SUX2BU]

Originally Posted by ChargedCamaro

Wow, what RWHP are you putting down? There must have been no spint at all!!!

There is a set of Hoosier racing slicks 295/675R18 GT for sale locally that I might pick up. Think they are any good?

426 rwhp. I didn't think anyone made 18" slicks. Are you sure you got the size right? 295/675r18 doesn't sound like a tire size.

[ChargedCamaro]

This is the craigslist ad that I found them on

http://losangeles.craigslist.org/wst...871604302.html

Maybe they are more for autocross?

[SUX2BU]

Originally Posted by ChargedCamaro

This is the craigslist ad that I found them on

http://losangeles.craigslist.org/wst...871604302.html

Maybe they are more for autocross?

Yeah, those are road racing/autocross tires.