Thread: Sub-frame installing....do's and dont's??

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Ok guys, I got yet another tech question for ya.
Im putting a front sub frame from a 78 Z28 on my 54 Chev 210 here soon, and I'd like to know some do's, dont's and tips on this job. Anything I should watch out for or certain steps to take mabey? I got a pretty good idea how to do it, but its my first time, so any advice would be great!!
Thanks.

Make sure the frame is setting level and secured at the point where you will cut it, don't want one or the other rail moving on you!!!! Measure, Measure, Measure, think awhile, look things over again, Measure, Measure, cut..... Then when you get the sub tacked in place, Measure some more, weld, fishplate, and gusset the joints back together.... Not a real tough job, patience and careful cutting and fitting is required. When it's all done, go out and enjoy your '54 with the good handling and braking!!!!!

EVERY THING Dave said. One thing I do is get the car up on stands pull the wheels and you can use a framing square or plumb bob the mark the floor for wheel centers. I draw diagrams with the measurements and go back to them while reassembly is being done. Tack it all together remeasure then weld it for good. I Always measure diagonely along with front to back and side to side. No one wants to drive a car that goes down the road sideways. Its not a hard job, but one that can go bad easily. Good luck and keep us posted. Pictures would be GOOD

Make sure you have a semetrical place on each sub frame rail to measure to. On Camaro/nova IFS you can use the shock hole. On G body(El Camino,regal...etc)the shock hole is off 1/2" from side to side so you have to locate a common pt. & center punch it for reference.

1. Make a fixture from lightweight 1/2" square tubing that will bolt into the fender attaching holes on the cowl and fashion a plate on the other end to locate the radiator core support so you won't have to fool around trying to get the hood latch located as well as the fenders.

2. Locate another running '78 Z28 in town somewhere and lay an angle finder on the lower control arms. Fab up 2 pieces of allthread and nuts/washers to hold your control arms (less springs) in place while you position the whole mess up under the car. This way, you'll know the exact ride height of the car when it's finished. You may have to tailor the front springs to duplicate the angle on the lower control arm, but all the front end geometry will be right.

3. If you're planning to lower the front of the car, position the subframe higher in the car with the control arms buttoned down per #2 above. Don't wait until after you've nailed the sub in to try and lower it. You'll screw up the geometry that way.

techinspector is right on with measuring all of the ride heights on an existing car. use the threaded rod to set ride height on removed sub. also, take a few minutes to hang your fenders to make sure your wheels are centered (before you weld anything). the stub can either be spliced-but do lots of planning and bracing, otherwise i've seen a very wise builder use the whole stub(locating the stub below your frame which gives you greater integrity with the longer mating surface)