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Pixel6
07-02-2021, 12:15 AM
I want to tow a 1991 S13 Silvia Ks club, Manual Trans, SR20DET, and an ATS (clutch style) 1.5 way LSD. It also has the Street Faction Engineering front bash bar.

So, with one of those Y shaped tow bars, can I reasonably flat tow (all 4 wheels down) with this? The bash bar already goes to the frame, so would be easy to plasma cut some brackets to weld to the bar for towing.

Should I disconnect the drive shaft and hang it up during longer towing or no?

A towing guide (quite old) shows that the 240sx manual can be towed 70mph/500 miles, with no further restrictions noted.

https://images.goodsam.com/newmotorhome/towguides/1992DinghyGuide.pdf

Does anyone here have experience in towing a similar S13 flat like this with no problems?

Thanks

Dirk Jan
07-02-2021, 12:45 AM
You'll be fine as long as it's in neutral, towing the car doesn't exert any different forces to the gearbox compared to normal driving.

inopsey
07-02-2021, 01:00 AM
the way i see this your trying to save some money by diy. how much you gonna save compared to potential repairs ? what does your insurance say about coverage with this type of road use? atleast dolly the car or remove the driveshaft. its your car and your money but imo your towing a $20k desirable antique and maybe should use a pro here or rent a trailer?

Pixel6
07-02-2021, 03:32 AM
the way i see this your trying to save some money by diy. how much you gonna save compared to potential repairs ? what does your insurance say about coverage with this type of road use? atleast dolly the car or remove the driveshaft. its your car and your money but imo your towing a $20k desirable antique and maybe should use a pro here or rent a trailer?

The purpose is to tow it behind an RV to look for land to buy, so this will be the exploring vehicle. It?ll be flat towed maybe a few hundred miles at a time, disconnected and driven around for a week or so, reconnected then rinse and repeat.

Weight is one consideration, and this is the lightest option. Trailers/ dollies add tongue weight, reduce fuel economy, and use up more overall cargo capacity. (I?m aiming for being light all the way around) I also like the idea of a tiny footprint on the rig, especially once unloaded... no trailer to constantly deal with. Only downfall is no backing up? but if I fab brackets on the bash bar and through the bumper, it should be quick to unhook.

Adding more time/hassle if I disconnect the drive shaft. but if I need to go that route, I?ll have a cradle designed to bolt the prop shaft up to secure it with quick-release t-pins for transport.

Good question on the insurance. I?ll ask them. It?ll likely be fine as I have a good relationship with the company I use.

I?ve serviced / rebuilt / replaced every part of the sub frame including cv?s, bearings, ball joints, calipers, rotors, bushings, control arms, diff etc, so it?s got a healthy (track ready) drive train. Front is the GKTech super angle kit with v3 knuckles. Energy Suspension bushings throughout. It?s well built, and the only thing I ever futz with at an 8 hour track day is tire pressure.

Would I love a low-key enclosed trailer? Yes? for 15 grand? No. I?m also not talking Harbour freight quality here? I?ll get a high quality tow bar. Modifying the bash bar becomes the simplest and most elegant solution, and probably the strongest. A drift shop with a pro FD driver on their team will be doing my welding.

So, more clear my intent? Other than tire wear (um, drift car) my only concern is premature wear on the ATS diff or wear to moving components upstream of the drive shaft.

Thanks

Pixel6
07-02-2021, 03:37 AM
You'll be fine as long as it's in neutral, towing the car doesn't exert any different forces to the gearbox compared to normal driving.

That?s my thinking? asking because I want to get this right. I?m hoping someone who has done a season with this towing method can let me know their experience. Surely someone on this forum tows /has towed this way.

burnsauto
07-02-2021, 04:23 AM
from the little reading I did from credible sources, sounds like you'll be fine with the car in neutral. No mention of removing driveshafts (though they do something like that with automatic cars, using a d.s. that can be decoupled). I figure if a publication like Car and Driver can publish something like that without legal stepping in and telling them "no", it should be pretty solid.

SupaDoopa
07-02-2021, 06:41 AM
This is towing 101. Just like you can tow it with the front two up [or even the back], as long as it is in neutral, you're fine. Disconnecting the driveshaft is for larger rig trucks being towed - not a normal commuter car. You'll be completely fine. Just keep in mind with a bash bar, your ground clearance is altered. Just imagine that you're driving the car you're towing when maneuvering terrain.

silviaks2nr
07-02-2021, 07:58 AM
Rent a storage unit somewhere and store the car until you figure out where you want to be then ship the car to you. Too many bad things can happen towing a car long distance in this manner and don't be surprised if insurance doesn't cover it when something does.

brndck
07-02-2021, 11:35 AM
Karl Wasabi used to flat tow his zombie car to the track and back. Never had any issues. Never removed the driveshaft or anything either.

My real question is, how do you lock the steering wheel and ensure that the front wheels are pointed forward? The column steering lock requires you turn the wheel at least a little to one side or the other before it will lock. Will you use a steering wheel holder like this?

https://images-na.ssl-images-amazon.com/images/I/51nriStNNgL._AC_SL1500_.jpg

https://www.amazon.com/SAVEMORE4U18-Steering-Wheel-Holder-Alignment/dp/B085FXN46Q/ref=asc_df_B085FXN46Q/?tag=hyprod-20&linkCode=df0&hvadid=417002368079&hvpos=&hvnetw=g&hvrand=13931273437157429215&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9031083&hvtargid=pla-909766483098&psc=1&tag=&ref=&adgrpid=92859401206&hvpone=&hvptwo=&hvadid=417002368079&hvpos=&hvnetw=g&hvrand=13931273437157429215&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9031083&hvtargid=pla-909766483098

SupaDoopa
07-02-2021, 12:22 PM
You turn the car on, angle the wheel in a specific way, turn car off, turn the wheel and lock it straight. Exactly as you thought.

Pixel6
07-02-2021, 02:27 PM
For flat towing, you turn the key one position to unlock the steering column. If you have all 4 wheels down and lock the wheel straight forward, physics would have you scrubbing the front tires as the car is dragged around corners, as the wheels wouldnt follow the turn.

If you unlock it the column, the car will just self steer. Also the same reason you cant reverse the rig with this setup, as the car would quickly self steer and jackknife.

The alignment has 8.5 of caster, so should always want to re-center. (Drift setup after all)
Front wheels: -0.05 toe out, -2.0 camber.
Rear wheels: .05 toe in, -0.3 camber.
So tire rear should be pretty minimal.

I have an NRG quick release hub for my Momo, and a hub-lock, which would keep reduce theft opportunists while the key is in the ignition.

Thanks for the advice and input. Im considering a lot of things for this setup. Just know I built this car to be a street legal daily driver, and a capable track car. So while many would cringe, just know it has been properly built to live that JDM dream. ngl it is simply amazing to drive… and that’s why I want it as a part of this journey.

mechanicalmoron
07-02-2021, 02:49 PM
The main reason for most towing prohibitions is automatic transmissions - modern autos have one pump on the input shaft, so if the engine isn't turning, there's no lube flow, and the rear parts of the tranny that are turning are splash lubed, if that - that's why they give a distance/speed, and then you have to drive it to re-lube things. It's fine to freewheel a manual in neutral (rules are made to be broken, I don't know about pressure lubed manuals, which do exist, and if the pump is run off the input or output - know what you have before applying my advice, but a stock 240 M/T doesn't have a pump)

Make sure it's in neutral, and leave the wheel unlocked so it can self-steer. a 240 behind an RV shouldn't be a problem, but do know that really bad things can happen really fast with a pickup, even at slow speed - it can self steer the wrong way and bind at lock, and take the light rear of your truck sideways, so you and the car are jack-knifed AND driving opposite directions. Think before you swing wide and set the towed vehicles steer wheels pointing the wrong way (a long distance between the rear axle and hitch can also cause problems).

I know some people say lock the wheel - maybe if you're trying to go fast with a small tow vehicle on the highway, but that sounds like a recipe for death - I subscribe to the "let it steer" school of thought, unless a thoughtful examination of the rig in question suggests you should do otherwise.

FrankFactor
07-02-2021, 05:03 PM
I have flat towed a few 240s without issue. I even flat towed another 240 with my 240. I flat towed a first gen Celica from SC to DE with my 240. Its so light that a standard tow bar far excedes any weight restrictions you will have. You will be fine.
You seem to know enough about(neutral, key in first position, proper alignment) to do just fine. People always argue the same things when you do things that seem odd to them (even though thousands of RVers flat tow everyday), about just spending a bunch of extra money, just do the extra pointless work, don't DIY, as if all this guarantee some kind of safety. Next people will talk about wear on your differencail gear by driving them backwards.... It will just make you second guess.
Just dont be a dumbass and do your research as you seem to have already done. RV sites are great for flat towing advice and safety tips. you will do fine. bring your 240 with you everywhere and have fun, live your life.

Pixel6
07-02-2021, 08:42 PM
cool thanks guys. kinda hard to find reliable info on these older cars being pre-internet.

just wanted to cover my bases and make sure I wasn't overlooking something dumb that would damage the car. but yea, unless I find a stellar trailer deal, I'll be going this route.