# forktruck to RTI conversion

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Cavalry, Jul 9, 2001.

1. ### Cavalry1/2 ton status

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I have a forktruck and no ramp. Is there a formula for converting lift to RTI?

"There is a fine line between hobby and mental illness"
Luke
84 K5

2. ### RaisedK51/2 ton status

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Well if i remember my math for triangles correctly , the Sin of the known angle 22 degrees, or 30 degrees, which ever you want to use, is equal to the opposite side, (the height of the fork truck) divided by the Hypotanuse, ( the deck of the imaginary ramp) so if you know the height you can figure out how far up the imaginary ramp you went then plug that into the regular RTI formula, that is if i remember my math correctly. Anybody?

RaisedK5

"Of all the things I've lost, I think I miss my mind the most!"

3. ### tRustyK5Big meanieStaff MemberSuper ModeratorGMOTM WinnerAuthor

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Sounds right to me...

Rene

<font color=green>Dyslexics of the world...UNTIE!</font color=green>

4. ### muddysub1 ton statusStaff MemberModeratorGMOTM Winner

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uuummmmm.................. yeah

scott,
1989 suburban 3/4t 4" lift soon to be rollin on 35s, tbi350

5. ### Cavalry1/2 ton status

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duh! and I argued with my math teachers that I was never going to use any of that stuff lol!

"There is a fine line between hobby and mental illness"
Luke
84 K5

6. ### MaxCrack1/2 ton status

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What he said...

q = angle of the ramp
h = hypotenuse (distance along the ramp)
y = hieght above the ground
x = distance traveled along the ground (not used here)

sin(q) = y/h

solving for h we get...
h = y/sin(q)

since q is either 22 degrees or 30 degrees
sin(22) = 0.3746
sin(30) = 0.5

I will assume you are figuring this out for a 30 degree ramp because the math is easier.

h = y/.5 = y*2

so multiply the height of the tire above the ground by 2 and that's your score on a 30 degree ramp.

Hey where's the nerd smiley?

That's because I'm the devil.

7. ### Grim-Reaper3/4 ton statusAuthor

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Uhhhhhhhhhhh Ok but that only got you how far up a 30deg ramp you traveled not the RTI You sitll have to divide the distance up the ramp by the wheel base and multiply times 1000 for the RTI figure.
The treachery of the old will to alwasy be to demean the young after they steal the fruits of their labor.
I'm old enough I forgot the part you figured out but smart enough to notice that you didn't complete the equasion.

It's not my damn planet monkey boy!

Grim-Reaper

8. ### DBLAZER1/2 ton status

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Heck , what they all said. BUT, I have run some pretty nasty trails and NEVER have I had to drive up a ramp to get to the end pf a trail!!!!

http://autotronixcaraudio.com

9. ### Twiz1/2 ton status

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That just about says it all - Dblazer! But, Just to compare one rig to the other, or one modification to the other, or even to figure out where to mount the shocks (something I've been battling with for a month) A RTI works pretty good.
An estimate on mine (if it helps)
-About- 43" off the ground, and -about- a 816 on a 30 ramp. RUFFLY- I didn't have a tire on, just ball-parked the measurements, and I didn't drive up a ramp- again, just ball parked the measurements.

but-Like DBLAZER said.
The proof is in the WHEELIN'

Twiztid

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