Flat towing a race car

Today I dolly towed my automatic racecar in neutral. It's got a rear mounted pump so I think it's fine but the trans is junk and being replaced so I'm not worried.

I don't mind dollying but I have worried about breaking the car(we've broken suspension parts on track) and not being about to get it home on a dolly. We usually tow on a braked two axle 20' equipment trailer. It's big and heavy but it tows SOOOOO nice.

I fabricated a flat tow adapter for my Prelude that ties into the bolt holes for the tow hook plates and to the subframe.  Haven't tested it yet, because when I went to pick up the car a good Samaritan lended his truck and dolley instead.

I don't know how strong the bumper is on a 79 Rx-7 but unless they made bumpers a lot stronger back then it might be really sketchy hooking just to the bumper.

Designing a flat tow setup that is strong, anchored in three points per side, and doesn't require cutting anything on the car was harder than I assumed.

I ended up going with 3 inch steel square tube radiused to make a lazy letter J shape.  The laying-on-it's-back J's bolt to the subframe on each side, and the sticking out parts provides a pair of receivers out front of the bumper.  Kind of looks like a piece of farm equipment.

The receivers accept a horizontal square tube, to which the actual flat tow bar connects (making a triangle).  This way the tow bar doesn't want to force the receivers outward, and the setup disassembles into smaller pieces.

I also have 8"x4"x3/16" vertical steel plates tying the side of the J tubes under the car to the inner fender well. They replace the stock tow hook plates, and keep the J tubes front wanting to twist.

Probably overkill but my thinking was, if I have to panic-stop or worse run into something with the towing vehicle, will the mounts hold up to the forces needed to stop the vehicle in tow?

DennisDoesEverything said:

I fabricated a flat tow adapter for my Prelude that ties into the bolt holes for the subframe. 

 

That is essentially how we built mine, We attached to the brackets that mount the bumper to the chassis.

I have used universal tow bars that attach to a bumper but never felt real comfortable doing it.

I flat towed an X-1/9 with a removable tow bar bolted to the frame; couldn't afford a trailer at the time.  It was OK, couldn't back it up.  I ran the Fiat tail lights with a flat 4 connector and ran them to the tow vehicle.  PITA part was swapping tires once you get to the Auto-X or track, not much room for tools and gas either.  If it rains, the interior fills with water (no glass or roof) so I MacGuyvered a tonneau cover.

I had pictures in Photobucket but not paying to get them back.

I built a tow bar that bolted to the factory tie down hooks and towed many thousands of kilometers with it. No issues.

Before that I built one that attached via chains to the tubular front bumper of a race car. No issues with that either.

I don't care much for towing but flat is probably the easiest way of doing it.

Reading through this I'm reaaalllly appreciating my enclosed trailer.  Big old tow pig is paid off and used/inexpensive trailer doubles as a garage in which the race car can live over the winter freeing up a garage spot for the project car.  

I drove home a few times in my Miata after track days and it was pretty miserable.  Climbing into the Suburban with AC and heated seats is glorious.

I have flat-towed my track car for three or four years now (i.e., a LOT).  I am in and out of the paddock faster than the trailer guys, don't need a special tow vehicle, didn't pay for a trailer and don't have to store it.  If I have to pay to tow once in awhile, I'm still way ahead.

I have flat-towed a Ford T5 transmission without disconnecting the drive shaft and never had a problem.  The moving parts are all sitting waist-deep in ATF.  If it bothers you, the T5 has a slip yoke so it's dead easy to disconnect the driveshaft at the diff.  Takes less time than getting a car strapped on a trailer.

JBasham said:

I have flat-towed a Ford T5 transmission without disconnecting the drive shaft and never had a problem.  The moving parts are all sitting waist-deep in ATF.

The fill plug is below mainshaft level, no?

If the input shaft is not turning, none of the gears are turning.  The only thing connected to the driveshaft is the mainshaft, spinning in the bearings and output gears.

The only thing connected to the mainshaft that might be contacting the oil are the synchro hubs.  Is that enough to splash enough oil around?

In reply to Pete. (l33t FS) :

Remco used to have a wicked badass interactive chart that listed all things flat-tow. Unfortunately, their website says they have discontinued production of towing kits, and the chart is DOA thru the wayback machine.
It only went back to 1996, but it said a '96 Mustang v6/T5 was flat towable up to 70mph constant with no special requirements. Based on that chart, and the lack of changes to the T5 in the post non-world class era, I have always flat towed or dollied my WCT5 equipped autoXer without removing the driveshaft. I haven't tracked mileage, but its a lot, and never been an issue.

In reply to gumby (Forum Supporter) :

Well, certainly practical experience is the best info.  Now I'm going to be trying to hunt down that chart.

Yes please! Cause that would make my flat towing even less stressful,  which is a nice thing!

I have towed my 85.5 SVO (WC T5 trans) with a tow dolly many hundreds of miles with the driveshaft connected and the trans in neutral and have never had any issues with the transmission.

Back in the day, way back, like early 1970's, we used to flat tow our drag car that had a spool using "tow hubs" on the rear.  They were hubs that mounted to the axle studs and had a separate set of wheel bearings and a free spinning hub with the same bolt circle as the axle.  You just pull the wheel/tire, attach the hub to the axle and then mount the wheel/tire to the free spinning hub.  Set the parking brake or leave the trans in gear, didn't matter.  The drag car had slicks so we just had a pair of old street tires mounted on steel wheels to use for towing.  Worked great.  I don't know if such a thing is still available or allowed, but it might be worth a look-see.

I own either 2 or 3 tow bars, all from harbor freight. I think your main safety issues with the tow bar itself are the adjustable width bolts on the tongue which allow the arms to swing out to different widths for initial setup. You could weld those in place if the bar is for one vehicle only, forever. I never bothered and haven't had a problem. I'd be most concerned with how the tow bar brackets are mounted to the car. Mounting to bumper beams could be done poorly or well. I try to bolt closest to the bumper's mounting points so that all the pushing and pulling is more or less transferring straight back through the mounts into the vehicle chassis/frame. If you mount far inboard/outboard of that you are probably doing it wrong. I also use as big/thick of washers as will fit in the backside to spread the load as most bumper beams are basically folded layers of sheetmetal and could certainly rip through if not done cautiously. The size and amount of hardware for the brackets is similar to what's used to mount small tow hitches on vehicles in the first place, and they're in tension, not shear. It's just up to you to mount it to something strong enough to take those forces. And then, safety chains!!

Only vaguely related but my dad once had a skid steer&trailer come loose from the truck. I don't know if the chains were a factor but he managed to catch it with the rear bumper and get it all stopped on the shoulder of the road. I wasn't there and don't know how hairy it really was but at this point im assuming that was some of the most important work he ever did in his life. Not a slight to him,  setting thousands of pounds of stuff loose at highway speed is as serious as it gets and if you do the tow bar just be damn sure you're doing your brackets right, and then check on them every once in a while. 

I was towing a Hyundai Stellar many years ago with the chain on style towbar. It was behind my 4 cylinder 86 S10 and as I rounded a corner in the rain the Stellar got into a wicked 4 wheel slide, came around, jackknifed the tow bar against the rusty rear bumper of the S10 and practically ripped it in half.  Fortunately I was pretty close and was able to limp it home. The S10 got a new 3x3 tube bumper the next day. 

Ill take a pic of the one I built for hauling Suzuki’s. It worked very well 

Couldnt track down a pic of the bracket off that car, but its essentially 2 pieces of 3" angle that bolt to the under side of the bumper and to the import/shipping tie down/pull loops off the bumper brackets. Then a 2x2 tube in front connecting it all and the hf tow bar attatchment points bolted to that. Sturdy and heavy, but comes off and on in 5 minutes with a good impact driver