Tongue Weight
04-26-2008, 08:33 AM
#16
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In our area, those who don't have adjustable axle locations (like a Trailex) and have tongue weight problems just back their rear engined cars onto their trailers.
04-26-2008, 09:10 AM
#17
Race Car
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That wouldn't really work for my 944 as they are pretty well balanced. The only way it would help is that the tie down points are under teh car so it could sit more forward.
04-26-2008, 10:53 AM
#19
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Jerome, equidistant is not correct way of getting the weight reduced by 1/2. Simple physics places the trailer in the middle 1 foot from the stationary pivot and 2 feet from the scale will yield 1/2 the force measured at the scale side. You also should use a round bar between the scale and solid pivot to minimize error introduced by the additional contact error created along the axis. should look like this
trailer force loading downward
facing trailer from tow vehicle
v
v
v
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
O O
scale pivot
(2X dist from trailer) (1X dist from trailer)
force equals 1:2 force at 1:1
trailer force loading downward
facing trailer from tow vehicle
v
v
v
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
O O
scale pivot
(2X dist from trailer) (1X dist from trailer)
force equals 1:2 force at 1:1
04-26-2008, 10:58 AM
#20
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First step is measure where you are. If you are less than 8-10% tongue weight (vs. total loaded weight) the trailer is going to wag. If you are over ~12% then that is not ideal, but if you have excess towing capacity and good wheelbase, you can get away with it. My tools and spares sit at the front of my trailer and the car is only 800 lbs. I carry far too much weight in the front, but my tow vehicle lets me do that safely. Otherwise I would have to relocate the tools to the rear, and they would have to come off before unloading the car - a real PITA.
Find a truck stop. Measure total weight with trailer, tow vehicle only (disconnected with both wheel and tongue support on the scales) and trailer wheels only while hitched. That will let you calculate tongue weight. If you get this data and want help with the calculations, PM me and I will figure them out for you.
Find a truck stop. Measure total weight with trailer, tow vehicle only (disconnected with both wheel and tongue support on the scales) and trailer wheels only while hitched. That will let you calculate tongue weight. If you get this data and want help with the calculations, PM me and I will figure them out for you.
04-26-2008, 01:37 PM
#21
I set mine up with a sherline scale using their instructions and it was all wrong... Went back to eye-balling it and the truck was much happier. Once I got it where I wanted it positioned with all my "crap" loaded up, my sherline scale was reading at 1275# on the tongue... My combo is a 3500 series dodge cummins diesel quadcab 4x4 with short bed and a Haulmark 24ft. enclosed. We're at probably 8500-8800# with the car gassed up, all four fuel cans topped off, and all tools/jacks/stands/spares.
Mike
Mike
04-26-2008, 05:47 PM
#23
Drifting
Couple of thoughts.
The rear (of the car) straps are at too severe of an angle to do much good. You'll probably need to attach them straight rather than crossed.
The front tow eye is not an appropriate place to attach at the front of the car, especially if you back the car on. Use 2 separate points on the chassis or wheel straps. In the event of a head-on collision the eye or bumper will get ripped off and the car will end up as a rear seat passenger.
My guess is as it's loaded now you have too much tongue weight. My trailer is similar length and same car and the center lift point of the car was about directly over the forward axle.
The rear (of the car) straps are at too severe of an angle to do much good. You'll probably need to attach them straight rather than crossed.
The front tow eye is not an appropriate place to attach at the front of the car, especially if you back the car on. Use 2 separate points on the chassis or wheel straps. In the event of a head-on collision the eye or bumper will get ripped off and the car will end up as a rear seat passenger.
My guess is as it's loaded now you have too much tongue weight. My trailer is similar length and same car and the center lift point of the car was about directly over the forward axle.
04-26-2008, 09:57 PM
#24
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Why do you have it backed up onto the trailer again?
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Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
2004 GT3 Track Car
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CLICK HERE to see some of my ancient racing videos.
Larry Herman
2016 Ford Transit Connect Titanium LWB
2018 Tesla Model 3 - Electricity can be fun!
Retired Club Racer & National PCA Instructor
Past Flames:
1994 RS America Club Racer
2004 GT3 Track Car
1984 911 Carrera Club Racer
1974 914/4 2.0 Track Car
CLICK HERE to see some of my ancient racing videos.
04-26-2008, 11:13 PM
#27
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Dan, I'll look at our 951 tomorrow, but I know that there are places to bolt tow eyes to on the front and rear suspension. That is the best way to get tow points. It has been a while, but I do not remember ever having any problems belting it to a trailer with just the hook straps.
04-28-2008, 08:27 PM
#29
Spend the money ($100) and get get the sherline scale. You will have times when you put other cars up there for various reasons or carry tires etc. A few inches either way on my trailer makes a 100lb difference. Better safe and confident than guessing.
Jeff
Jeff
04-28-2008, 08:41 PM
#30
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Buy axle straps and run them through the wheels front and rear. Cross the ratchets straps. Position the car with the middle of the door centered between the trailer axles. Take the truck for a spin. If it wags like hell, move the car forward. Repeat until it feels ok.
I had a trailer and Jeep like that once. I never felt real stable over about 65mph, even with so much tongue wait you could see it squat (trailex, so no load distributing hitch). With my Dodge now I don't even care about too much tongue weight and could tow at 80mph if I choose.
I had a trailer and Jeep like that once. I never felt real stable over about 65mph, even with so much tongue wait you could see it squat (trailex, so no load distributing hitch). With my Dodge now I don't even care about too much tongue weight and could tow at 80mph if I choose.
