If you lifted it 3", and you extended the shock 3", then you should be pretty close to where you started.
Seems it should work that way, doesn't it?
The fact is that lifting your truck doesn't change the travel of your shocks, but it
does change where your vehicle sits in that range of motion.
Lets say that a stock lifted truck with OME shocks looks like this:
|-----:-------|
Where | is the min/max of the shock travel, and : is where the truck sits.
If you add in a 3" lift, it would change it to look something like this:
|---------:---|
You have the
exactly same total travel, but what you did is exchange down travel for up travel. Same total range of motion, just more biased towards one end or the other.
By adding the spacer what akarilo did was something like this...
|-----:-----[]|
So you are trading some of that up travel back for down travel. The problem is....you can only have so much compression before you bottom out your shocks.
The OME specs don't add up, as I had similar concerns when planning this mod. When you put a tape measure to it it is a different story.
Something I'd meant to do, but never actually did, was measure the OME shocks for min/max.
The numbers I got (and I rounded off to the nearest half inch, so they're
relatively accurate) are:
Code:
Model Body Min Max Range Upper Lower
N73 13.50 23.50 10.00 Stud Stud
N74E 14.50 24.50 10.00 Stud Eye
Compared to the original specs:
Code:
Model Body Min Max Range Upper Lower
N73 13.93 24.17 10.24 Stud Stud
N74E 14.57 24.40 09.83 Stud Eye
I suspect that the way OME measured the front shocks is a little weird due to the difference between stud and eye. For one, the L's have the same specs front and rear, when the rears should be about 1" different because of the difference between eye and stud.
Regardless, you have a
little bit more room on compression for the front than the original specs I posted, but less than half an inch more.
The math still doesn't add up. If you were sitting at 16" when fully compressed, your mod basically turns that 16" into 13". You're still half an inch of too much compression.
By bumps are in effect, lowered, as they are mounted below the spacers. I do not have a full 3" of spring lift.
I would still measure your front fully compressed and make sure that you are not over compressing the shock. Even with the spacers, you are going to be awfully close to maxing out your shocks.
From my experience, a shock can touch bottom without damage, as I am not catching air or anything.
From my research, not true.
Over compressing or over extending shocks is bad on them, and can blow them out. Many shocks (such as the Pro comp's, and I suspect the OME's) have internal bump stops on the end so that if you extend them all the way it will not damage the shock. AFAIK they cannot or do not provide the same bump stop when fully compressing.
Bottoming out the shocks is more likely to cause damage than over extending them.
If you fully extend them, the only weight that you have is the axle/wheels/tires, and only half the weight at most (as the weight will be split between the two shocks). Additionally, over extending is more likely to happen at low speeds than high unless you're jumping the truck.
According to my '97 FSM, the front curb weight (measured at the front axle) is just under 2600 lbs. Bottoming out means that you will have up to that 2600 lbs (less the weight of the rear axle/tires/wheels, and split between the two front shocks, though depending on the situation it may not be a 50/50 split) coming down.
force = mass x acceleration
Considering the weight difference between the axle alone (maybe a couple hundred lbs) and that (up to) 2600 lbs, which do you think is going to have more force, especially given that the second scenario is far more likely to have a higher acceleration?
Adding spacers to your shocks is not a bad idea, in fact I specifically mention it in the Pro Comp thread (or at least I did before Woody wiped it out...hmm, should check and see if it's still in there).
But you need to be absolutely sure that you are not going to over compress your shocks in the process.
TBH I really don't think you are going to, given how bound up the front end is and considering that you
did space down your bump stops some. But I think that you are a lot closer that you realize, so I would suggest going out and measuring it just to be on the safe side.
