Hi all. I have been buying all the parts I need to convert my 56 to full independent suspension. I chose the corvette rear because IMO it looks the best under the truck. I got an amazing deal on the full kits for both front and rear. Half the price of what you see them going for on eBay and in amazing shape! (PM me if you would like to know where. Great guys! Not sure if I can say their name since they are a business and not a site sponsor) I went with the 87 C4 rear end because that will let me use the Wilwood big brake system in the back. I always hate when you see a car or truck with bigger rims and then these tiny little rotors and calipers behind it.

Anyway. When doing my planning I spoke to the folks at Wilwood about their rear big brake kits. The front rotor cap comes with the holes drilled for both 4.5 and 4.75 bolt patterns. But the rear only comes drilled for 4.75. When asking them about this he told me that there is still plenty of space to have the cap drilled for the 4.5 pattern. Well that made sense and I carried on. Not realizing or even thinking that the rear bolt pattern is based on the actual hub assemble on the C4 and not really changeable.

My question is does anyone know or have any experience in changing in the lug pattern on this? There is a set of rims I have in mind for the truck and they only come in the 4.5 pattern.

I can't image I'm the first person to have run into this. The rear hub assembly is cheap enough in itself to replace. I'll most likely be doing that anyway just to have brand new bearings. But right now it seems that I'll have to have them drilled for the 4.5 pattern. But want some input from the great minds around here.

And I apologize to the purists out there. Please be a little bit comforted that the C4 suspension is the only thing I plan on doing that is not Ford.

 

To add some pictures since I know you all like them.


Here is a picture of the rear hub. I've found a bunch that seem to have holes drilled in the addition to the 4/75 pattern. I'm curious if those are for the 4.5 pattern. I've found that other Chevy models do have the 4.5 pattern and do have a similar style read hub. So I'll bet the manufacture just has the outer flange drilled for both patterns. But again looking for any other input.

 

I will be using billet aluminum adapters to go from 4.75 to 4.5 lug pattern, I have not used them before so I am a little concerned on how strong they are, but they seem to be popular.

 

Ya I know that's an option. But that would lessen the offset I'm looking for on the wheel.

 

Well it looks like I'll be using the converters as well. I'll have to put some small tubs in the bed in order to fit the 10" wheel and tire so that leaves me more room for my front space anyway. So I'll be using the converter to push the wheel out further to be closer to the fender.

 

Here's the problem you will have with the OEM Corvette hubs...there are 3 "extra" holes in the flange, one large and two small. The large hole is there so that you can get a socket into the hub mounting bolts...the two small holes are opposite the large hole and serve to counterbalance the flange assembly. The easiest way to get around this setup is to get wheels, like Cragar, that will mount to both 4.5 and 4.75 inch lug spacings.

 

Thanks Charlie. That was the info I was looking for before. But now that I know I have to tub the bed anyway. Or widen the fenders it's not as much of a concern and I can use the converters to make the change.

 

Here is a diagram that you may find helpful...

 

Thanks again Charlie. Could you give me some details as to what axle those numbers are being pulled from? I'll be running a 87 c4 rear setup and that is 61.5".

Right now my truck has a stock rear end. And my measurements from drum face to drum face is 60".

So I'm not sure where those numbers are coming from. Thanks!