Cobrabill I got mine from a guy that builds them in NJ. It's open trailer. The most important things to get with the trailer are the following. You need the trailer bed low as possible unless you like scrapping off the paint under the
oil cooler. I have a solid diamond plate trailer. Weight is 1,900 lbs. empty. It is very stable with the car on it. At times forget it's back there. I go 1,000 miles to the run&gun each year since 99. I have had the trailer since 97. I was renting uhauls for the car to go to ERA and Paint shops and have things changed in my car. 3,500 axles with 4 wheel brakes on each wheel. The cheater trailer only have 2 brakes. 2 5/16 ball for the hitch. It's rated at 10,000 lbs. WELD the nut to the bottom of the hitch. IMO I wouldn't use one of those multi adjustable hitchs with 3 balls and 12" on up and down movement for long or high speed towwing. Get 4" drop axles and the heavyer tire for the trailer. It is the next rated range up on the tires. Make sure you have all 4 wheels balanced before long trips. I have grease buddys on my hubs and each gets 4-5 pumps of grease before a long trip. I check the brakes everyother year and adjust. The breakaway battery needs to be replace every 3-4 years. DON'T leave your truck plugged into the trailer for long periods. My trailer battery killed my truck battery twice. It sucked having to pull the cobra off the trailer to jump start the truck in a truck stop.
Nitrogen in the tires does help the tires control heat and give longer life. I saved the best for last. SPEED, I have driven trailers over 50,000 miles. Have had 1 set of tires replaced from poor design on the 5 wheeler, no charge. I have had only 2 blowouts from the tires having bad wear patterns. Rotate the tires every 2,000 miles. They build a toe and camber into the trailer for stability at high speeds. Limit your speed to 70MPH. You are not going to get there any faster. Loosing control of your rig is a real scary deal. I had a deer problem in W.Virg. at 2:00am on the turnpike and spun the whole rig out. The ABS sytem on my dually didn't help, I was only doing 60 MPH. A change of underwear was needed.
I am happy with my trailer, the thing I hate is the 1 hour it takes to rap up my car with car cover, moving pats, foam strips, and tarps. This protect the cars paint. I also have double mud flaps on the rear tires, Diamond plate at the extendsion of the fenders and dirt skirt at the bumpers. My gas milage is a .6 mpg drop with the 4,000 added pounds behind the truck. SBC 350 motor. I am going to go with a haulmark low hauler in the future. The height is the same as my truck, so the gas milage will not be bad. I use the trailer for hauling. Fixing the car at a track I get a garage space. You can still work on the car in the trailer just remember this a 5'5" ceiling.
Sorry for the long return. Park your trailer on stone when not using, it's better on the tires or jack it up for long term. You get flat spots when on asphalt, and cement. I have seen guys loose the whole rig from high speed driving. Save the speed for the track, you have to get to the track first alive to enjoy the trip.
Rick L.