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juggernaught
01-02-2010, 04:45 PM
Awhile ago I installed a set of Rancho 9000's(?). The ones with the valve adjustment. Anyway just got to thinking. I purchased shocks with 3 inches of stroke in both directions. Is this enough stroke along with the springs to crawl moderate to serious trails? I do run leaf springs.

I have about 4-41/2" of total lift and 33" tires. Will the shocks stop the wheels from contacting the ground? What is the normal/average travel on other shocks out there? Any input would be welcome.

tufcj
01-02-2010, 08:20 PM
No real way to tell. The way I did my CJ was to go down to the local 4x4 shop, who had a RTI ramp. I went without shocks, ran it up the ramp until it was crossed-up to maximum, then crawled under and measured fully extended and fully compressed. I repeated with one front wheel on the ramp, and one rear.

Once I had the measurements, we went to the books, and found a shock with about 1" more travel than I needed on both compression and extension.

Bob
tufcj

juggernaught
01-03-2010, 10:17 AM
Thanks. That sounds like the way to go. Is there any way to tell with the jeep just sitting? I have about 9" of space to the bump stops in both the front and rear. Unfortunately, I do not have the motor(v-8) installed presently, but don't think it will compress the front stock leafs much.

My guess is that I may have greatly limited my total travel by having only 3" available in either direction. I believe my sitting shock lengths were about 15"(rear) and 18"(front). Probably can't get much more travel than 6" with a short overall length like that. Is it "normal" to have an equal amount of travel in both directions with a shorter shock? How about a longer travel shock?

tufcj
01-03-2010, 07:39 PM
Trouble is that the longer the stroke, the longer the body of the shock has to be. The longer the body, the more likely it is to bottom on compression. The stocks mounts are OK with stock suspension, but as soon as you add a lift and/or increase articulation, the mount locations will probably have to change to make full use of the increases.

On my CJ, to get a shock with enough travel to allow full articulation, I had to raise the upper shock mount on both front and rear. In the rear, I added a crossmember, and leaned the shocks toward the center of the vehicle.

Bob
tufcj

juggernaught
01-04-2010, 07:43 AM
Heh tufcj... see you have same model as my '78. How about some specific numbers?. How much lift do you have? How much room between the bump stops front and rear? Are you still running leaf springs? How much travel do you have on your shocks? I heard that some Ford shock towers easily convert to a cj. Is that what you used? How much taller are your new towers? Thanks.

tufcj
01-04-2010, 01:19 PM
I'm running SOA and shackle reversed on 1.5" lift YJ springs, custom made by Alcan Spring. Total lift is about 7".

Front upper mounts are Wagoneer, very similar to the Ford mounts. Front lower are modified GM, which came off the narrowed GM 44HD front housing I run.

I run a 1" body lift, so in the rear, I added a crossmember above the frame rails forward of the gas tank, I made it as close to the floorboard as possible. The lower mounts are 100% home made. The top of the rear shock leans toward the center of the vehicle, and there are several holes for adjustment.

I believe the shocks are Rancho RS9002s on all 4 corners, it just worked out that way.

Trouble is right now I'm in Colorado, and my Jeep is stored at my brother's house back in Illinois. I just closed on a house last week, so I'll go get it soon.

Bob
tufcj

juggernaught
01-04-2010, 03:22 PM
The rs 9001's show about 8+ "of total travel. No rs9002's listed. So if you have 7 inches of lift and only 8 inches travel total........say 4" in either direction, then your shocks are actually limiting your wheel travel?

I have 3 1/2" susp. lift and 1" body for approx. 4 1/2" total. But my bumbstop has 9 inches of space. I wunder if something with more like 12-15 inches of travel would benefit my rig? I guess the real question is: Will my axel actually ever meet my bumbstop?

tufcj
01-04-2010, 06:00 PM
I looked at the Rancho catalog, and they must be RS9012's with just shy of 14" of travel. I have Rancho 2" bumpstops in the front and 3" in the rear. The do work differently, since they contact the spring, and not the axle like factory, due to the SOA. MY CJ only has about 4-5" of compression, and can just about max the shock on droop. I positioned the mounts with compression and droop in mind. I also use a mounting pin faced front/rear, so the shock twists on the bolt as the axle articulates. A 2-tab or side/side mount causes the shock to twist the bushing, and can limit travel.

This is the kind of flex I get.

http://img.photobucket.com/albums/v475/tufcj/Jeep/moab3.jpg

Bob
tufcj

juggernaught
01-04-2010, 07:01 PM
That makes more sense. I'll keep the "shock pin" orientation in mind for later. Thanks for all the info. At some point I will be redoing my shock setup, but first need to get engine/tranny reinstalled.

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