Towing 4 wheels down

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Towing 4 wheels down

Postby Rsylvestri on Wed Sep 29, 2010 9:07 pm

Just wondering if I can tow my '77 911 four wheels down behind my motorhome.
Standard 5 speed 915 tranny??
TIA, Rick
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Re: Towing 4 wheels down

Postby Dan Chambers on Wed Oct 06, 2010 1:43 pm

Rick:

I thought about doing that for a while, then changed my mind and bought a trailer. Personally, I wouldn't do it unless it's a short distance on the street (no FWY).

The problem I see is, unless you remove the "dog-bones" on both sides and free up the wheels from the transaxle, you've got all those gears, R&P, and final out-shaft spinning in the tranny while towing. Unlike an american car/truck where you can disconnect the u-joints/drive shaft and spin the wheels freely, the trans-to-wheels connection on the 911's/915 is a buggar! And I'd hate to think what would happen if the car bounced into gear at speed. :x Even in neutral, I think the heat generated in the gear box while towing might age your fluid, and working parts prematurely? I'm guessing here. :roll:

Is your trailer de-commissioned?

Maybe Steve G. or someone else more familiar with the running gears can explain it better? Steve G.? Mark K.? Jae Lee? Your thoughts?
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Re: Towing 4 wheels down

Postby Rsylvestri on Thu Oct 07, 2010 7:09 pm

Dan, This is for my '77 street car towed once or twice a year behind the motorhome on vacations. Soo... if I removed CV's/axle from tranny or road wheel no harm, no foul ??
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Re: Towing 4 wheels down

Postby ttweed on Fri Oct 08, 2010 6:59 am

Rsylvestri wrote:Dan, This is for my '77 street car towed once or twice a year behind the motorhome on vacations. Soo... if I removed CV's/axle from tranny or road wheel no harm, no foul ??

Rick-
I don't think there is any problem with flat-towing a manual tranny car w/ CVs hooked up. Maybe an auto tranny could be damaged, but I don't see how it would hurt a 915 like yours. Yeah, the shafts would spin, but they would do that if you drove it there, with the additional strain of having the engine torque running through them. I can't see how it would accidentally shift itself into gear either, but if you were concerned about that, you could lash the shifter into neutral somehow. Bob Bertrand has flat-towed his 914 to Zone 8 events all over the southland for years. He does remove his front valance before hooking up the towbar. I'm not sure if that is to prevent scraping it or to bolt up the mounts for his towbar.

You could try shooting him an email and asking him about his experience with it. The last one I had for him is rgb91424 at yahoo dot com.

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Re: Towing 4 wheels down

Postby Jad on Fri Oct 08, 2010 1:17 pm

My neighbor use to flat tow his RX7 racecar everywhere. As long as the wheels don't fall off, or similar, it works great. Loose a bearing or something, hard to get it home. Other than that and tire wear, much simpler and smaller tow vehicle needed.
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Re: Towing 4 wheels down

Postby tb911 on Fri Oct 08, 2010 10:03 pm

I flat towed a 914 for a couple of years. No problem whatsoever, other than the hassle of having to keep the keys in the car so that the steering doesn't lock. (Disconnect the battery!)
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Re: Towing 4 wheels down

Postby Rsylvestri on Sat Oct 09, 2010 8:33 pm

Thanks Guys!
I'm still in the decision process, my wife's next car might be towable SUV.
If not I'll go with towing the street 911 a few times a year.
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Re: Towing 4 wheels down

Postby genikz on Wed Dec 08, 2010 7:50 pm

My brother and I both flat-tow our cars, and have probably logged 2000 miles this year, with no issues whatsoever.

He has a '78 924 (5 spd) and I have an '88 924S (5 spd).
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Re: Towing 4 wheels down

Postby sean_v8_914 on Thu Dec 16, 2010 9:00 am

we flat tow the 10jreen often. I have a trailer but flat towing is less hassle that de-trailering at events. DO NOT BACK UP.
I put some skinny tires on it and go. race rubber in teh bed of hte truck. I also put a medium tensioned bungee around the steerign wheel to dampen teh bump steer since AX alignment is a tad squirelly on teh freeway
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Re: Towing 4 wheels down

Postby Mike on Fri Dec 17, 2010 8:25 am

My only experiance was ground towing a baja bug to the desert with no problems.

Just be sure to keep it in neutral.
The worst blown up VW bus motor I ever saw was one that was ground towed for hours on the freeway in first gear.
Serious mechanical over rev, top half of motor was gone. :cry:

You can back up a trailer but it's not easy to back up a vechicle that is being ground towed.
Backing up your rig with the 911 in place, the 911 front wheels will just want to go to full lock and bind your tow bar.

Might want to be sure you motorhome has some good mud flaps too.
Maybe you can tow with a protective 911 front bra installed?
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Re: Towing 4 wheels down

Postby sean_v8_914 on Fri Dec 17, 2010 8:48 am

slightly OT:
there was a guy at an AX that had a disposable clear bra material. it was cheap . sold on a roll like saran wrap. better than blue tape and probably cheaper since painters tape gets pricey when you cover half your car lie some guys do.
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Re: Towing 4 wheels down

Postby Mike on Fri Dec 17, 2010 9:30 am

sean_v8_914 wrote:slightly OT:
there was a guy at an AX that had a disposable clear bra material. it was cheap .


http://www.buyroadwrap.com/
It's only 2.5 mil thick but if you use 2 or 3 layers helps better with rock chips.
It is thin material so it needs to be removed with in a week or it shreds and takes longer to remove.
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Re: Towing 4 wheels down

Postby Rsylvestri on Wed Jan 05, 2011 7:46 am

I've got a bra that I'll use.
I'm thinking of making or buying a plexi glass protector I can attach to the
Roadmaster tow bar I inherited when I bought the motorhome.
Thanks Guys
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Re: Towing 4 wheels down

Postby sean_v8_914 on Wed Jan 05, 2011 7:56 am

there are 2 factors that generate heat in the gear box. one is teh heat transfer from teh engine. the second and most significant is the friction and load placed on teh meshing gears by the power being applied. if a gear box could jump into gear by a road bump, it was toast already.
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Re: Towing 4 wheels down - UPDATE

Postby Rsylvestri on Thu Aug 09, 2012 9:14 pm

Finally got around to making a braket mounted to the skids on the front of the 911. Took a roadmaster tow bar (Blue Ox would work too) cut the front mounting plate and welded to braket I made. Did a wiring harness set up for removable tail lights that stays with the car when not towing.
This summer we went Boise, ID. , Tahoe and back home with no issues. One minor mistake, 1/2 block without turning the key to the first position so the steering wheel turns free :oops: No harm but scared me a little.
With the weight of the car I couldn't feel any feedback other than a few miles an hour less over the grape vine. So if anyone else is going to try this DO IT. It was well worth it having a grocery getter/canyon carver to play with on vacation.
:beerchug: Rick
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