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2003 TJ Ramp Pictures

TJ Suspensions on the Ramp

Articulation Ramps are nice to be able to see if anything is getting close to hitting.  I have seen rigs with tremendous articulation get so crossed up that they can't move on the trail, while the mildly setup rigs drives through the same spot.  These were shot on the clubs 20 degree ramp.  I will have to get a picture of a stock Rubi since I don't have one from the first time.  I feel that a score between 800 - 1000 will do just fine on most of the trails. 

  stock suspension diso'd OME suspension disco'd
  sideview stock suspension disco'd  
Stock Suspension
Distance Wheelbase Score Est. Tire Height
62.5 93.4 669 21.38
Stock Suspension Disconnected
Distance Wheelbase Score Est. Tire Height
82.5 93.4 883 28.22
OME Suspension Disconnected
Distance Wheelbase Score Est. Tire Height
98.0 93.4 1,049 33.52

RE4.5 LA Ramp RE4.5 LA Ramp RE4.5 LA Ramp
RE4.5 LA Ramp RE4.5 LA Ramp RE4.5 LA Ramp
RE4.5 LA Ramp RE4.5 LA Ramp RE4.5 LA Ramp
RE4.5 LA Ramp RE4.5 LA Ramp RE4.5 LA Ramp
RE4.5 LA Ramp RE4.5 LA Ramp RE4.5 LA Ramp
  RE4.5 LA Ramp  
Rubicon Express 4.5 Long Arm
Distance Wheelbase Score Est. Tire Height
120 93.4 1,285 41.05

 6" AiROCk Ramp 6" AiROCk Ramp 6" AiROCk Ramp
6" AiROCk Ramp 6" AiROCk Ramp 6" AiROCk Ramp
6" AiROCk Ramp   6" AiROCk Ramp
6" AiROCK with RE Long Arm
Distance Wheelbase Score Est. Tire Height
104 93.4 1,113 35.58

I had figured that the 6" AiROCK would net me less than the 4.5 Long arm, but I didn't think I would do worse than the RE 3.5 Superflex.  The biggest limiter I saw was in the compression.  I couldn't stuff the rear tire as far as I could with the other lifts.  I was to limited by the shock length.  I did try different combinations of bag pressure to see if I could get any better score, but nothing worked to really improve it.

My Ramp Opinion:
I use ramps mainly to check clearance and rub issues. It's nice to be able to flex it and see what rubs and what doesn't.

Here is the basic problems with a ramp.
1) The people measuring, unless it is the same person for every measurement, doing it exactly the same way the measurements will change.
2) Tire pressure, try this experiment one time. Run the ramp at street pressure, then run the ramp at trail pressure. You will get a better score at trail pressure.
3) Tire placement. The tire needs to be run on the ramp near, but not over the edge of the ramp. I've seen them run up the edge of the ramp with half the tire off the side of the ramp (i.e. hanging below = larger score)
4) The Ramp construction. Take a look at the mesh on the ramp and see if is pushed down or is pushing down with the weight of the tire. If it is, you can actually get a higher score.
5) Take identical rigs, but with different tires and run the ramp. You will get different scores. Now run identical rigs, but have one with a wider axle. The wider axle will get a better score because we do not calculate for axle width. example would be a rig that could rotate its front axle completely vertical. With a 36" axle it would only be able to get up the ramp about 34" vertical height (compensate for tire on ramp and other tire hitting ramp) now, put a 48" axle on this rig, guess what, you could now go up about 46". Who has greater flex? In reality neither.
6) The number of times you run it up the ramp before you measure. I never thought about this until I saw an actual ramp competition and one of the guys mentioned it. Limbering up the springs is the way it was described. I tried it and got a better ramp score, not much, but better.
7) Reality wheelbase measurement. Actually measuring from hub center to hub center, then comparing the ground measurement to the ramp measurement of wheelbase.
8) Ground slope the ramp has to be perfectly level in all aspects. Not very likely. Also the surrounding area has to be perfectly level so that all the tires of the ramping vehicle have to be on the same plane as the ramp.

In my opinion the best way to run a ramp score (at least until I figure out the axle width computation, and build a 3d laser holographic terrain mapping and vehicle ramping system) is to measure from the ground to the lowest part of the tire on the ramp squared off of the ramp (takes away possible ramp ground slope). This will give you height to ground. Put it in to the calculation below and it will give you a ramp score. Any monkey with a level can do this height. 

(Tire height/ sin(ramp angle))/ wheelbase * 1000 = ramp score

Examples: (I used my scores with my known measurements.)
(33.5/ sin (20))/ 93.4 * 1000 = 1048.68 ramp score
(33.5/ sin (23))/ 93.4 * 1000 = 917.95 ramp score
(33.5/ sin (30))/ 93.4 * 1000 = 717.34 ramp score

This page last updated: 16-Apr-2008

Content and Design © 2002-present WanderingTrail,  Ron Seegert
Common Sense and Safety should always be observed when working on your vehicle or doing modifications. Jackstands, wheel blocks, disconnecting the battery are a few of the basic safety precautions that should be used and may not be mentioned in the write ups on this site. You are responsible for your own installation, these write ups are a helpful guideline and should not be taken as an official installation instruction. My write up may be different from the kits currently out there, so alwasy double check the manufacturers installation instructions when installing anything. I try to keep the site up to date with changes that have occured as I discover them, but may not have the latest unless someone lets me know. If you feel that an install is above your capabilities after reading my write ups, I recommend getting together with a club and getting some help. Only a few times have I needed to employe some actual help from a shop to get something done. Usually welding or A/C work.
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