How to set rear axle height? s10

[b-mac]

I'm working on my 49/s10 swap. I bought a 8.8 Ford Rear end, and a universal triangulated four link kit.

I need to figure out exactly how far to come down from the frame for the rear axle.

My thought was, if I could find the center-line for the front spindles, from the factory, then I could subtract my front drop components (2” drop spindles, ½” taller ball joints, ½” for LS weight difference?). From there, I do the math to move the rear axle to the right spot.

I have these dimensions:
https://www.gmupfitter.com/publicat/...B/LDPDF/ST.pdf (pg 35 of 63)

If you follow my math above, and note that the top of the highest part of the rear frame is 10.40" above the normal top of frame (500), and subtract my 3"ish front drop, you're left with 7.4 down from the top of the high part of the frame. Or 3.4 down from the bottom of the frame to the axle center. Then subtract 1-5/8 radius of the axle... Seems like we're getting too close.

Maybe the real question should be: people with s10, 3" rear drop blocks, stock frame; whats the distance between the top of your rear axle and the bottom of your frame?

[joedoh]

I think maybe you are making it too complicated. bolt some wheels on front and rear, roll the axle under, set ride height with the front suspension on the ground. weld in your 4 link. make sure you approximate the weight of the bed and rear fenders before you install springs.

[b-mac]

I think you are right. It's a bit difficult to find true right height because none of my concrete is flat. Also, I'm missing the doors, interior, fluids (including cooling system) etc, that would probably have some affect on front ride height.

I do like your idea about saving the springs for last. I have some 12" coil-overs I'd really like to use, so I'm going to try to make them work, however I have to build my cross member(s).

[Rude Dude]

There are a lot of four link or four bar install on you tube that have good info.

[b-mac]

Yeah, I know. I've watched some of them. I'll do a little more YouTube research tonight.
In one of the more informative videos I've watched, they actually tacked the axle to the bottom of the frame to keep it in the perfect spot. Then they built their links (parallel), but then when they were done, the notched the frame 3 inches.
I don't have room for that, but I did pick up a scrap of 3" square tubing, thinking I could tack that to the frame, then the axle to that, and I'd have 3" of travel before I hit the frame.
Problem is, I don't know if that's enough, or not. And I don't want to end up with a bunch of rake (especially negative). I'd like to keep the running board parallel to the ground.