Narrowing Malibu rear frame

you could leave the stock frame as a unit and build within the that unit... and actually never remove the body but the rear floor area within the tub area ...a little more work but ..... brandon

 

just wanna let you know that a lot of the rear suspension on my 61 olds either interchanges or is damn close to the chevelle. If you wanna split hairs the arm rests are the same part number so go figure.... I understand your POV and I wouldnt show up to M*** or Billetproof in my Chevelle but this is strictly a fabrication question plain and simple about modifying a rear frame. I want my car low and I want a tire wider than a 235 in the back so I gotta do what Im doing. Riding low is traditional and you gotta do mods for that and this is no different.

I appreciate everyone giving your advice on the subject and not beating me down cause its not a "traditional" car for the forum. I think from the ideas here and the point that I should do it on a jig, Im gonna get some 4x4 .250" square tubing and make a homemade ch***is jig and do it that way. I was hoping maybe theres a way to do it without a ch***is jig as I helped/observed a buddy do a '29 frame simply jigged up on a piece of MDF but Im thinking this may be a bit different. More or less I was looking for ideas of building the frame squared out and dimensionally correct as opposed to actually what clip to use or anything like that. Ill search about using a ch***is jig as it will probably answer more questions than my post is generating. Thanks for the input Ill check out whats up about that part of it.

 

Personally, I'd go see if an 80s G-body like a Monte Carlo had a narrow enough frame to work and if it did just backhalf it with that. Even if you find one that's rotted, you could cut the back part off and use the rear of your existing rails. Measure 800 times, weld once, make sure it's square. The advantage that gives you is it already has a coil spring setup, as long as it's narrow enough for you you only have to weld it up, you don't have to fab up and engineer an entire rear suspension from scratch. It won't be the prettiest thing in the world, but when it's so low that a pack of cigarettes becomes a speed bump, who's going to see it anyways?

 

Quick and dirty - After leveling your car on some blocks or jackstands...Take a piece of 1x3 (or 2x3) box tubing and weld in between the rear frame rails roughly where one of the body mounts are (about the front edge of the gas tank) across the back.

Then do the same approximately where the frame kicks in (narrows) from the main rails just in front of where it kicks up.

Then cut out the rear crossmember where the spring/shock mounts are so you have some working room.

Then make (or buy) a couple frame rails (kick ups) to connect the pair of 2x3 crossmembers you already welded in place, narrow enough for the tire clearance you desire.

Then add a tubular crossmember approx 5 inches (depending on the style of mounts you plan to use) behind the rear axle centerline in between the kickups you just installed. This will be where you put your upper spring/shock mounts later on.

Add some gussets and/or tubular cross bracing where needed then cut out the old frame kick ups and plate the open areas of the existing frame to the box tubing crossmembers you added earlier.

Once the framing is secure, cut out the center of the front 2x3 crossmember (so your driveshaft will fit) and plate the end onto your kickup.

Add a couple lower trailing arm mounts at the front, most likely on the 2x3 box you welded in earlier.

Slide your rear end back under there and add shock/spring mounts and the upper 3-Link crossmember and mounts as desired.

Put it all back together, modify wheel tubs, etc.

Like I said - Quick & Dirty. It won't win any car show awards but it'll function and get you down the road without too much h***le or having to remove the body.

Give me a call if you need more specifics. I've done this a couple times.

Al in CT

 

man that is the best advise a guy could get without paying, thank you very much thats what I was looking for and knew it could be found here and you actually having done it makes it all that much better. If I need to Ill contact you but you spelled it out pretty well and I think I can get out of the forest so to speak. Thanks you wouldnt believe how much I appreciate it.