Torsion bar adjustment?

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Torsion bar adjustment?

Post by HenryJ »

dominusmortis wrote:... how far did you have to crank you t-bars (as in the bolt being flush with the block)?
Each vehicle will be a little different. The bolt threads are an indicator, but there are other things to watch more closely. Good bars, bolts and keys can crank the suspension beyond its working limits.
The Trim height specifications are in our stock information pages on our website. I do not suggest exceeding the maximum Z height specifications. I do adjust to the maximum.

All that said the factory specifications are somewhat open to interpretation as the manual diagrams have the ball joint on the wrong side of the spindle. Use your best judgement following the directions.

It has been my experience that the stock keys can not adjust in the crossmember far enough to be a problem as long as the front end can be properly aligned. The upper a-arms and adjusters limit the amount you can increase Z height and still have correct camber and caster. The stock keys can exceed this in adjustment, unless you have added lots of weight to the front like a big bumper, winch or both.

"OK, that all sounds good, but ...WHAT? :crazy: How am I supposed to figure that all out?"

If the back end is stock. Adjust the front to level it our with the back. Watch the key in the crossmember and make sure it does not bottom. That will have about 5/16"-7/16" threads left on the adjuster bolts. Now head straight for the alignment shop and get it aligned. Let them know they can drop it a little if they need to in order to align it properly.

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Re: crew cab on zr2 frame (aka baja crew cab)

Post by dominusmortis »

so the max z height is 128mm, correct? doesnt that screw with the ball joints, tie rod ends, and cv axles?

EDIT: what about looking intoperformance torsion bars or putting full size ones of the same length in?
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Re: crew cab on zr2 frame (aka baja crew cab)

Post by HenryJ »

dominusmortis wrote:so the max z height is 128mm, correct? doesnt that screw with the ball joints, tie rod ends, and cv axles?
No. That is only .4" above the minimum.
EDIT: what about looking intoperformance torsion bars or putting full size ones of the same length in?
Why? Are you carrying more weight? A V-8 engine? Do you want it stiffer?
Changing the spring rate will not change the trim height.

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Re: crew cab on zr2 frame (aka baja crew cab)

Post by dominusmortis »

well, i cant seem to find the max z height in the forum ( or im just blind). and as for the torsion bars, i wasnt sure if putting heavier bars in would affect the ride hieght. however, i will be putting a tube bumper and winch on the front of the truck. so i figured with the extra weight on the front, the t-bars might need to be upgraded.
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Re: crew cab on zr2 frame (aka baja crew cab)

Post by HenryJ »

Probably not.

The logo at the top is linked to our website. There you find links to the Modifications page and also Stock information. You can find the Trim height measurements in the stock info, along with many other resources.

The search here works pretty well. Punch in a key word or two and you should find lots of information. This site has been active for over a decade now so we have gone over almost everything that can be done to these trucks.

I think you will find that replacement bars are not really an option. Fullsize bars will not fit without major fabrication. I am not aware of any aftermarket bars being currently available for our application and those that were are very expensive making them cost prohibitive.

One member here used aftermarket keys to regain his Z height after a custom bumper and 16,000# winch. Soon after he found the stock IFS to be insufficient for his needs and the increased weight. He now runs SFA up front. I would suggest that might be a better solution should you need more than the MML can offer.

How much adjustment do you have left after reaching max Z height with the current load? You should have enough to add a winch with no problems as long as it remains a reasonable size. Adding synthetic line will make its use a bit safer and cut weight as does a light weight fairlead. There are always options. That is how mine was set up.
I had a front hitch instead of a heavy bumper. Check out all your options.

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Re: crew cab on zr2 frame (aka baja crew cab)

Post by dominusmortis »

well. i guess the max z height would be 512mm. either that or my math is really screwed...
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Re: crew cab on zr2 frame (aka baja crew cab)

Post by HenryJ »

Your math is pretty screwed :lol: 116-128 mm (4.6-5 in)

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Re: crew cab on zr2 frame (aka baja crew cab)

Post by dominusmortis »

so if i t-bar crank to 116mm, i should be good (in theory)?
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Re: crew cab on zr2 frame (aka baja crew cab)

Post by F9K9 »

The measurements are confusing but, he is quoting GM data.
Z Trim Height..............* 4WD (except ZR2).........116-128 mm (4.6-5 in).........122 mm (4.8 in)
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Re: crew cab on zr2 frame (aka baja crew cab)

Post by dominusmortis »

i know i sound like an idiot, but when i did this to my 90 blazer, i just did it. i put the bolts flush, backed them off 2 rotations, then backed off till level. however, i need to get this right.

so the max z height is between 116-128mm, with a preferred reading of 122mm. let me know if im getting this right plz.
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Re: crew cab on zr2 frame (aka baja crew cab)

Post by HenryJ »

dominusmortis wrote:so if i t-bar crank to 116mm, i should be good (in theory)?
116 is the minimum. 122 is recommended, I suggest 128, although you may have to back down a little to properly align it. All are within the normal operating adjustment range. The stock keys will exceed this. You surely did that with your Blazer from the sound of it.

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Re: crew cab on zr2 frame (aka baja crew cab)

Post by dominusmortis »

after the t-bar crank is done, will i need to get new shocks? what about the sway bar links? also, would stock ZR2 shocks (40mm?) fit with the t-bar and boise spring kit?
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Re: crew cab on zr2 frame (aka baja crew cab)

Post by HenryJ »

dominusmortis wrote:after the t-bar crank is done, will i need to get new shocks?
No , you are still within the stock operating range. You have done nothing to extend the suspensions operating range.
what about the sway bar links?
Only if you desire to improve the bushings
also, would stock ZR2 shocks (40mm?) fit with the t-bar and boise spring kit?
The fronts, no. The rear, only if you extend the operating range by installing longer shackles. The BSW kit will not require longer shocks. Again it is still the normal suspension operating range.

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Re: Torsion bar adjustment?

Post by DutchBiker42 »

T-Bar cranks destroy front ends. Just FYI.
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Re: Torsion bar adjustment?

Post by HenryJ »

Too far , yes. Within the range of operation is acceptable. Ride height adjustment.

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