My '91 s10

Some guys at work one time re-created the double forklift just for fun, that scared the shit out of me, especially since I was standing on the forks of the top one. It's sure one way to get onto the roof after a storm makes the ladder unstable and unusable. A truck would be no problem, lol.

Was thinking about what to do with this truck tonight... here's what I got so far for the rear.

Frame:
- box frame all the way back with 1/8" plate,
- possibly x-brace
- re-create ZQ8 brace with 2x4 tubing
- build cnotch into frame, maybe a SMALL step that doesn't involve cutting bed (about an inch higher than stock framerail)
- SD triangulated 4link without axle bracket (crossmember, links, axle tabs)

Rear End:
- built ford 9" with 3.73's and an aggressive posi
- weld upper link tabs to pumpkin
- weld lower link tabs to axle tubes
- Wilwood disk brake setup (depending on budget)

Suspension:
- dual adjustable coilovers, completely undecided on travel, spring rate, brand, etc.
- belltech front facing swaybar from blazer if it doesn't interfere with link bars, otherwise rear facing bar

suggestions? I know the SD 4link isn't the greatest geo, but i'm kinda scared to get into custom mounting points. I'd much rather use a pre-fabbed crossmember and the stock leaf mounts beefed up...

dont go with an SD kit. as a person who did exactly that (with custom hardpoints), its not that much harder to start from scratch, and saves you a whole lot of headache.
especially the stock leaf mounts. unless you are running a ridiculously tall tire, those points are way too high to get any reasonable geometry out of.

and why 9" why not just an 8.8"?

Don't let me discourage fabrication, but I picked up the factory brace and bolts for about $60 shipped.  Might be more for shipping since you are up in Canada, but another option.

Brace: 15741812
Bolt x4: 11515756

Also if you do fabricate it a 2x4 tube is way overkill.  I'd at least drop down to a 2x2 and I'd wager the factory brace is around 1x1 or so.

Also if you do fabricate it a 2x4 tube is way overkill.  I'd at least drop down to a 2x2 and I'd wager the factory brace is around 1x1 or so.

from what i can tell most of the forces would be in tension/compression so a fairly small thin walled tube will suffice, key is to have it loaded well (how you mount it to the frame)

IMAG0086 by TheHarley, on Flickr

I used to think I knew a fair amount about frame building, but it's obvious i'm wrong. Would it be a good idea to make a jig outside of the factory frame to hold the rails in place, cut the crossmembers out, box it, weld in new crossmembers, then fab the link points from there? Need to find some free time and begin research again.

I wouldn't cut out all the stock crossmembers to box the rails unless I was going to do custom crossmembers too.

This is the area where the lines start to get really blurry IMHO. Once you've cut out the stock crossmembers, boxed the rails and done custom crossmembers, why not just do a back-half, or a firewall back? If you're doing a firewall back, why not cut the stock horns and do a SFBD? Oce you've got only the section of frame between the horns and the firewall, why not do a bumper to bumper custom frame? If you're doing a custom frame, why not do a custom suspension that beats the pants off of anything you could do with stock? If you've got a custom frame with a SFBD, why do a ladder frame when you could do a space frame with integrated cage? By the time you're done just taking that next step, you've got a NASCAR truck that looks like an S10.

I have difficulty not justifying my way all the way into a race car for a DD though, hopefully you don't have that problem.

I think this is where humbly taking a step back and assessing both our skill and time can help where to draw the line.  Can we or do we want to wait 1, 2, 5 or 10 years to complete the project?  Will taking a smaller step help me build the skills to take a larger step next time?

I'd love to do a space frame because it is the best for everything I want this truck to do.  Heck I'd really enjoy having a back half with 4 link to take that next big step in handling, but I also want to drive the truck and I have much to learn to do either of those.  I know I can learn the skills and accomplish either, but that pushes enjoying the truck down the road another 1, 2, 5, maybe 10 years.

That's why I'll be wrapping up the 5.3 and frame swap this year and running the leaves out back for awhile longer.  While I'm enjoying it this summer I'll figure out the backhalf and 4 link to hopefully accomplish that for the year after.  I've got some ideas for the next step beyond that, but I'm also thinking that might be a place to start with a fresh truck/body.

I suggest figuring out where you will need new cross members and what ones will need to be removed for the 4 link.  Remove those and box around the rest.  Use some extra tube to weld across the frame where you remove a cross member and go from there.

agreeing 100% with Harley on this.
enjoy what you have for a bit, do more research, get smart. then cut stuff off.

I pulled the truck apart this year to focus on the frame, i'll be putting down around 450hp when it comes back to life and I don't trust the C-channel frame with shitty leaf springs. I was considering full frame with C6 subframes, but like you guys said, how long do I wanna go without this truck and risk losing interest?

I'm set on keeping the stock front half of the frame, and I'd rather not back-half it without a frame table, that's why I said keep the stock rear rails and simply box them for strength. This is where some CAD toying comes suuuuuper handy.

I think you are on the right track with boxing the frame and the 4 link.  Not to be insulting, but just advising that going bigger than that may be beyond what you are looking for and can accomplish right now.  I'm in the same boat and I'm not even doing a 4 link on this go around.

As far as frame strength most of it comes in the actual height.  Boxing will strengthen, but not as much as many think.  Although combine it with a ZQ8 frame brace or the like and it should improve the frame's resistance to twisting a decent amount.

Check this thread for some reality on frame design and strength:

http://www.blazinlow.com/forum/showthread.php?78141-notch-stresses-on-the-frame

No offense taken, I simply don't know enough to trust myself to go further than boxing right now. Sorry, when I said strength I meant twisting. Although I'm sure i'd be fine since I don't plan on ever getting traction in the rear, i'd rather do it now opposed to later!

I'll check out that thread

Harley really nailed it in his post. Taking an honest look at your skills and timeframe can be very humbling, if not a little depressing, but it has to be done if you actually want to enjoy your truck.

I've found the key to be having multiple vehicles. I have a fairly fun and very versatile full size truck, but it lacks more than a little in the fun factor department, especially around corners, so I have my blazer and when my blazer is up to par for a daily driver, I can ditch the payments on my current DD and roll that money into the next project. It's all a very annoying balancing act, but what isn't?

I have my 98 sonoma as a fun/low daily, but it's a 2.2 so at $70 for 500km of not being nice to it, that's affordable. Keeps things balanced.

Had a blast at the shop tonight with a good friend, welded up some rails for his bike/snowboarding




I'd like some constructive criticism on this work. It's 2 x 4 x 1/8" wall tubing, .023 wire with gas. I know I could step up to .035, but I'll be doing lots of sheetmetal too.

Those are at least 1000X better than my welds!

haha, thanks!

Frame is officially 100% stripped, except for the front e-brake cable I think. It should be off to sandblasting in a week or two. Here's a picture before the leafs and trailer hitch came off. The leaf bolts slid right out, I was ecstatic. Anti-Seize is my best friend, second in line to people who use it though!

Cleaned up my spot and sat the frame down, 100% stripped and awaiting sandblasting. Not much of an update but i've been slacking.

i've always wanted to make a brace to mimic the el camino/F41 braces (but better of course).  most of your subframe cars have a similar brace.  Nismo even makes a special one for the 240s.  I'd like to make one that I could take out in case I have to do some work.



Detroit Speed makes an aftermarket one:



here's a nismo brace just to show:



it's basically a beefed up stock one with an extra bar joining it together.