Speed: (sped) n. Magnitude of a velocity. The act or state of moving rapidly. An unquenchable thirst for more.
OK, I made up the last one, but you know what I’m talking about.
In the world of instant gratification, motorsports is king. If a 10-second quarter was great yesterday, it’s just a start today. Because we have such a need for speed, tire and wheel manufacturers have to provide new products at the edge of technology. We want every bleeding ounce of performance.
To help you provide the best options for your speed-intoxicated customer, I’ve assembled the latest information about DOT drag tires and lightweight wheels. Read carefully: While there are variations of these products, many are marketed toward the same end user.
BFG g-Force
First, consider the BFGoodrich g-Force T/A drag radial, reportedly the first-ever DOT drag radial tire. Originally designed for RWD vehicles, many said this was the tire to have at the track. Driveable on the street, it eliminated the need to haul half of the shop along with your slicks in the trunk.
Since its inception, more sizes, and even a new tread pattern, have been added, along with sizes to fit compact cars. In case you haven’t looked closely at the available sizes lately, here are a few that are available: P345/55R15, 29.8-inch OD and P325/50R15, 27.9-inch OD. These 15-inch choices will work great on older vehicles with small brakes, but to fit the late models you need the larger 17-inch, like P275/40R17 or P315/35R17.
Before we get too deep into specs, I want to bring a few important points to your attention. First is air pressure. BFG recommends no less than 12 psi at the track. The correct amount of air pressure will change based on altitude, ambient temperature and weight of the vehicle and its distribution.
During the ‘test and tune’ runs, record as much data about these variables as possible, including the length of burnout. A pyrometer may help you get an idea of the tread temperature, as well. Check the outer edges and center of the tread area. You want a similar temperature across the tire.
Next, as you lower air pressure to increase launch traction, you are adding rolling resistance and drag at the other end of the track. Do not assume that the lowest pressure is correct. It’s all about the right combination. You can’t unlock a safe by only knowing two out of three numbers.
Notice that I specifically mentioned the OD of the tires. Gear ratios need to be matched up to the OD depending on the length of track 1/8 compared to 1/4 mile. Bigger is not necessarily better. A tall tire on a 1/8-mile track may not allow the vehicle to get out of the hole quick enough, resulting in higher 60-foot times and forcing you to catch up at the end. Conversely, a smaller OD tire may lower 60-foot times, but you may run out of tach and be out of the power curve before the end of the 1/4 mile. Screaming at the tach doesn’t make the car go any faster believe me, I’ve tried.
The new tread that was introduced a couple of years ago has more sizes, especially for compacts, more 17-inch sizes like 205/40R17 for the F-bodys, Vettes and Vipers, and there’s the monster P345/30R18, requiring 12 inches of rim width to sit on!
A word of caution though: BFG doesn’t recommend using bead locks for these tires. Also, warn your customer not to drive these tires on a regular basis, especially when the road is wet. These tires like dry, straight lines, not curves.
Hoosier Bias, Radial
Next comes Hoosier drag tires. Offered in bias and radial, you have a choice to make. The Quick Time/Quick Time Pro bias-ply tires use a “super chain link” tread.
They are offered in a range of 14- and 15-inch sizes in ODs from 26 to 33 inches. The Quick Time Pro also has a 35-inch OD tire available. The Pro series tires were recently redesigned to match the profile of the slicks more closely. One more unique size the 275/55D14 would be a good option for an old muscle car, like a Hemi ‘Cuda running 14×8-inch Magnum wheels.
Next are the Hoosier drag radials. This lineup includes a brand new size P275/60R15 an all-around good tire size, as it fits on an 8- to 8.5-inch rim width, doesn’t usually have clearance problems and is a good middle-of-the-road choice for traction and rolling resistance.
There’s a big word of caution here, though: Hoosier plainly states: “Hoosier DOT tires are not intended for highway use.”
Nitto Drag Radial
Now, do a 180 and consider the Nitto (www.nittotire.com) NT-555R drag radial. This tire has only one 14-inch size 205/55R14 several 15 inchers with good applications, 16- and 17-inch sizes for Mustangs and Cameros, and an axle-twisting 335/30R18.
The difference in this tire from the previous: Nitto claims the tire delivers up to 15,000 miles on the street under “normal driving conditions.” With 6/32nd of tread depth molded in, compared to 4/32nd for the others, this tire should have better street manners.
Now For Wheels
Several months ago, we discussed unsprung weight and how a heavier wheel literally drains the available torque being transferred to the ground. Make sure that you spec a strong, lightweight wheel that matches up to the tire.
Synonymous with racing is Weld Wheels (www.weldracing.com). Its Aluma Star is available from 15×3.5 inches up to 16×16 inches. And, the Magnum import drag wheel is available from 13×7 to 13×10 inches and 15×3.5 to 15×10.25 inches. The only bolt patterns are 5×100 and 4×100.
(A note on bolt patterns: 5×4.5/4.75 is offered in all sizes, but 5×5 starts at 15×10 inches, and 5×5.5 is in 16×16 inches only.)
Another option is the Racelite Drag. Built in 13×8 inches and 15×4 inches, these wheels weigh in a scant six pounds. Bolt patterns are 4×100/4.25/4.5 and 5×100/4.5. That 4×4.25 gives you something to offer for the Ford Focus. Tell your customer, though, these wheels are not for street use.
Finally, Volk Racing offers a streetable, one- and two-piece forged wheel. Available from Mackin Industries, these wheels offer light weight and high strength, combined with a multitude of sizes, offsets and various disk shapes (centers) to provide the maximum caliper clearance needed for your customer’s vehicle.
The TE37 is available from 13 to 15 inches, 4×100/4.5 and some 5×100/4.5 in 15-inch sizes. The CE28 is available from 15 inches (as little as 8 pounds) to 19 inches, mostly 5×100/4.5 bolt patterns. Staggered fitments and big brakes are not problems with either of these. Just make a caliper template, and order the correct profile and pad thickness.
Speed-hungry customers and these products could add some extra cash in your drawer.