Question for anyone who has used the Corvette C4 rear and the Flat Out kit: Are the half shafts at a right angle to the frame, or do the trail back a bit? As I am setting mine up using the measurements, my halfshafts trail a bit. The reason the set up is important is that toe does not seem to be adjustable like the factory setup is. So I kind of have to hit the toe correctly from the get-go.

Now this is the front to rear angle and toe....not the up and down angle

 

You doing this on a 56? And are you doing something different for the install? If not then toe and camber are all 100% adjustable. But you may run into an issue of the toe rods hitting the frame if you are going for a low stance. If so you'll have to go to another setup. Flat out makes a really nice kit. I actually wrote the instruction on the install.

But my half shafts are not trailing. They are perpendicular to the frame. Maybe you have something off a bit?

 

I may very well, and that's why I am paused. With the factory setup, if you need to move the front four link mounts forward or back, you use shims or remove them. The front of the kit are solid, so even if you adjust the rear tie bar, if the third member is fixed, and the front mounts are fixed, how do you adjust toe?

 

Toe is adjusted by the two upper most aluminum bars that run parallel to the half shafts. One end connects to the rear part of the knuckle and the other to the center of the differential. Toe is adjusted by a swedge bar.

Check out out this pic.

 

My camber rods are original OEM steel, but same function. My point unless I am missing something is that you can crank on those bars all day long and not go anywhere if you hold the differential in one place and the four link brackets in one place. If you want the wheel to pivot back, you have to also move the four link mounts back too right?

 

Oh it's a 55. I never answered that I think.

 

The 4 link won't do anything to adjust toe or camber. Only wheel placement in the opening. You can get adjustable ones and the advantage of these is to extend or reduce wheel base for better turn in.

The stock toe bars are adusted by tightening or loosening the home joint at the end by the knuckle. The knuckle can pivot because of the u joint that half shafts are connected at.

If you have absolut solid toe jars that are not adjustable then those are no stock c4 corvette. What year was you donor? Can you post some pics? I replaced mine and have the stock ones. If ya need them. But again depending on your ride height you may have to replace them to reposition.

 

They are adjustable. Just not aluminum in my case.
I think your point that I was concerned about at first is that moving the spindle forward or back around the pivot of the third member makes a much smaller influence on toe than does pivoting the spindle itself. Makes sense now that I think of it that way!!
I wasn't thinking of the spindle itself pivoting, but rather the spindle and shaft pivoting around the third member. Now I get it!

I'm surprised however that I have so much angle in the horizontal plane on the half shafts at the kit measurements. I need to remeasure everything and see if there is an error on my part.

 

Cool! Glad I could help. Please feel free to message me if ya have any other questions.

Another thought that came up with your shafts not being perpendicular to the frame is the placement of the wheel in the fender opening. It may be a good idea to put the bed back on before you do to much of th drilling. I'm nervous for you that the wheels may be way off center.

 

I scribed a line at the kit recommended location, and by going by their dimensions, I'm not spot on it. I'm going with the stock location after looking at the wheel placement with the box on. But with the very much larger wheel and tire I am looking at, I'm not 100% confident that this will be ideal.
Anyhow, some more measuring is in order.

 

When I first installed my C4 IRS using the F/O Eng kit I ran into the same problem with the half shaft alignment. What I found that I had done wrong was that I had the camber bars installed inverted...this set the hubs at the wrong angle. Here is a pic showing the "T" bars installed correctly.

 

I can see how that could be done, but mine are in right side up.
Also, it's my angle looking from above that I am struggling with.
I used the FO front kit and I had no issues. I'm being kind of a putz somehow on the rear though.

 

Oh and Outlaw sent you a message too.

 

It is the "angle looking from above" that is affected. When the camber bars are inverted the hub is kicked forward/backward causing the hub to move and thus the orientation of the half shaft to change. Good luck, you'll get it dialed in.

 

Thought I would report. All brackets are in the places advised by the instructions except the front 4 bar mounts. Those had to go about 1/2" forward of advised. The wheel is in the correct location with the box on, and there is a slight back rake to the half shafts as seen from above, which is what they recommend. Great kit, but the one dimension had me snaggletoothed for sure.

Now motor mounts. Are there kits that any of you have used for BBC in an F100? I would want it pretty generic so I could weld together. But starting from scratch seems tedious too. Anyone?