Just added a Cherry Bomb and got an RTI Score

DarbyWalters · **Posted:** Sat Oct 13, 2007 12:10 pm

Finally cut out the stock muffler and "neckdowns" and welded in a Cherry Bomb...sounds better...just a low grumble...not loud in the least. After I did it I wanted to get a good look at it so I went to a 4x4 shop and went up their ramp. Interesting RTI Score...OME 2.25" lift with tires aired up to 44psi for mileage and both sway bars still connected.

Front ways up...505 on a 20 degree ramp

Backing up........527 on the same 20 degree ramp

Not bad IMO...if I lowered the air pressure to 32 or so it would have been a bit better. I was impressed how well the OME and long travel rear shocks performed.

***My 2002 KJ with no rear sway bar/custom front sway bar disco and 265/75/16s scored a 670 on a 20% ramp Front Ways***

Goglio704 · **Posted:** Sat Oct 13, 2007 12:21 pm

RTI score is a new term to me. Is it a standardized measuring system for what is normally called flex?

DarbyWalters · **Posted:** Sat Oct 13, 2007 12:41 pm

Ramp Travel Index...measures how far up a ramp you travel before a wheel lifts. It is an indication of how well you will flex...it is not the "end all factor" but it is a good indication. I think a stock KJ has ~340RTI.

Another way to look at it is this: If you had a vehicle with a 104.3" wheelbase (like our KJs) and you pulled a 500 RTI score, the KJ would have traveled up the ramp 50% of the wheelbase...or 52.15".

Another way to get a RTI score without a ramp is to put a jack under one front tire and lift until another tire is just touching the ground. If on a KJ you could lift it 17.8" up...you would have a 500RTI on a 20 degree ramp.

0311_DoC · **Posted:** Sat Oct 13, 2007 12:44 pm

DarbyWalters wrote:

Finally cut out the stock muffler and "neckdowns" and welded in a Cherry Bomb...sounds better...just a low grumble...not loud in the least. After I did it I wanted to get a good look at it so I went to a 4x4 shop and went up their ramp. Interesting RTI Score...OME 2.25" lift with tires aired up to 44psi for mileage and both sway bars still connected.

Front ways up...505 on a 20 degree ramp

Backing up........527 on the same 20 degree ramp

Not bad IMO...if I lowered the air pressure to 32 or so it would have been a bit better. I was impressed how well the OME and long travel rear shocks performed.

***My 2002 KJ with no rear sway bar/custom front sway bar disco and 265/75/16s scored a 670 on a 20% ramp Front Ways***

I wanna see pics of your cherry bomb install......

DarbyWalters · **Posted:** Sat Oct 13, 2007 12:49 pm

I will try to post a pic later. What I did was cut the pipe in front of the OEM muffler right on the joint to get rid of the neckdown...then welded the CB directly to that...then I took a piece of 2.5" exhaust tubing and welded to the back of the CB and expanded the other end to go over the OEM tailpie section...pretty simple...and cheap.

Here is a great site with a few different types of "calculators":

http://www.4lo.com/calc/rticalc.htm

Discoing the front sway bar makes quite a difference...another members ride:

***Can't do that with a front sway bar***

DarbyWalters · **Posted:** Sat Oct 13, 2007 3:25 pm

One pic...haven't finished the paint job underneath but you can get the idea...very minimalistic

0311_DoC · **Posted:** Sat Oct 13, 2007 3:47 pm

very cool, what kind of paint are you using? some sort of hi-temp i assume :roll:

DarbyWalters · **Posted:** Sat Oct 13, 2007 4:29 pm

I am a pastry chef good at baking enamel...lol

Just added a Cherry Bomb and got an RTI Score

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