Chevy & GMC Vans

The problem with torsion bars and upgrading to a "heavy-duty" bar is they are a straight rate or linear spring and not progressive like a coils can be built and tuned. This is why GM uses progressive dampers (think bump stops) on lower control arms and designed the IFS to ride on these dampers and add some progression to it.

Gabe, how much stiffening work on the chassis do you think will help when you have that big rectangle cut out of the roof and all the corresponding body twist and flex? This is one of the concerns I have when considering whether or not to poptop.

Congrats on the new van!

Good point on the pop-top. I can't remember where, but I did see someone tie the rear into the front subframe. It did look pretty heavy, but also resembled a full frame when completed. I was wondering if people have used OV's chassis stiffeners and if these helped at all. At one point Dean seemed to thing rock rails would help quite a bit, bit I dont think I'll need them and dont want the extra weight.
For the most part though, I think the body twist would be more of an off road issue where axles are under greater twisting loads. I could definitely be wrong about that, but hoping to tidy up the on-road handling (and its not that bad.. not good, but not bad... I'm just trying to get a better cornering feel)

Actually.... I just contacted a local offroad fabricator about potentially churning out some 1 ton equivalent idler arms for our vans. He's looked at this website and is deciding if it makes sense. I think if we could guarantee selling 15-20 sets, he'd do it. I think we could do that no problem.

Gabequest: if theres any chance of this happening you can put me on the list of interested parties. Good stuff!

Just an add on to this heavy duty front end stuff. If this comes to fruition it would be a huge help to anyone thinking ( as I am) about going posi up front. I posted this link in its own post but in case you missed it and are really looking to go nuts up front ( as I am ) here it is

http://www.syty.net/forums/showthread.php?t=102077

There is also engineered performance inc. that builds a limited slip for our 7.2's so friction or torsen? Decisions - Decisions

gabequest wrote:Good point on the pop-top. I can't remember where, but I did see someone tie the rear into the front subframe. It did look pretty heavy, but also resembled a full frame when completed. I was wondering if people have used OV's chassis stiffeners and if these helped at all. At one point Dean seemed to thing rock rails would help quite a bit, bit I dont think I'll need them and dont want the extra weight.
For the most part though, I think the body twist would be more of an off road issue where axles are under greater twisting loads. I could definitely be wrong about that, but hoping to tidy up the on-road handling (and its not that bad.. not good, but not bad... I'm just trying to get a better cornering feel)

Gerald @ OLV does have some newly designed HiPo adjustable leaf spring hangers that tie into the subframe. They require welding a plate onto the ends of subframe and then bolt in place.

http://www.overlandvans.com/0104_suspension.html

Keep up the good work on improving the suspension, and steering and frame extensions.
I did install home made 2"x 2" frame extenders on my 2003 AWD Astro. The frame extender also makes a nice side jacking point. The frame extender made it easier to add side step Nerf bars.
I did post a bunch of photos a couple months ago. Basically, 69" long piece of 2x2 steel box tubing, 0.125 " wall thickness. It bolts to the leaf spring hangers with Uni strut 4 hole flat plates, then it bolts to the sub frame with uni strut parts also. The Overland one looks a bit stronger and the welding would help stiffen it but I wanted a bolt on so it could be removed. I was able to use existing OEM holes in the subframe and grade 8 hex bolts etc.

AP

Capt'n.. no posi for me and thanks for the note on wanting the idlers. I'll call him next week and see what is minimum would be.

As far as chasis stiffeners... I'll call Gerald and see how long the wait is.. but i'm leaning towards them.
Thanks again guys, keep the ideas coming!

No posi?!?! GASP!!! Ya I understand. The stock setup works so well. I'm just hoping that the two piece axle setup from the S-10's will keep any squirrels content as with it I'll only be running one powered wheel ( left front) up front until I hit the switch and then it's power to all four
PS glad to have you back in the game

Not sure what type of body mounts your van has but when I upgraded to polyurethane bushings it made an immediate improvement in the van feeling more connected to the road .

Slicky,
Any noise with the Eurethane subrame mounts?

Strover,
Maybe the trick with our torsion bar set up is to extend the progressive dampeners so they nearly contact the lower control arm. At this point with the lift they seem kinda worthless, since they don't contact the lower control arm unless really compressed. Maybe we like that for more flex, but potentially we could get better cornering if lowering them a bit. Not sure if the loss in travel is worth that, but also not sure how much flex we actually get. Havent done my due diligence with flexing this thing.

None that I have noticed , Stroverlander is also using them . Maybe he will chime in too.

Just ordered the eurethane so thanks.
Has anyone figured out how to upgrade the braking abilities of the 4x disc setup? I've replace the front pads, and about to do the rear and maybe a brake fluid flush, but with the larger tires and weight, I'm not that happy with braking ability.

OE quality rotors, Hawk LTS pads front/rear and decent brake fluid has worked great for me - excellent stopping power, no fade, some dust.