You would have to weld up the existing holes (possible strength issues if not done right) and then redrill for the new pattern. You cannot fit the 5 bolt pattern into the 4 bolt with enough clearance to be acceptable.

Cheers, Rod

 

You're right, I had assumed the BC was the same for 4 (108mm) and 5 lug (114.3mm), but there is a difference which complicates things. I did a 4 to 5 lug conversion on a Porsche 914 and it was a matter of simply drilling four more holes since one of the studs was already useable. The 6.3mm increase in BC results in the bolt holes being 3.15mm (~1/8") closer to the edge of the hub. I don't have the diameter of the hub so it's hard to judge. Any mechanical engineers out there?

 

no matter what I try the holes interfere

 

I've see lots of redrilled axles over the years. Yes you can do it and it's safe. Should not need to weld in old holes unless one is in the way. Take to a machine shop and they should be able to do it. I've seen in the past that guys just machined off the old studs and left the root of the stud in the axle. Did a Google search on the subject and came up with this ... may be some useful info. Cheers, Jim.

Google

 

save the frustration...buy fox-length 5 lug from Richard Oben. Great price, much stronger than stock, the right length, no worrying about bearing/seal surfaces, AND they have the correct sized center for the mustang hub-centric wheels.

:beer:

 

I paid $16.00 each at the U-Pull it yard, bought 4 at that price. The hardest part is getting that 5/16 pin out of the housing, bring a 5/16, 6 point socket.
HTH
Tim

 

What Wade said

Here is a picture of the turbocoupe rotor machined for 5 on 4.5. As you can see it works for the rotor but would not hold studs securely.

Breeze Automotive Factory Five Racing

 

I have had a couple sets done, you can get by with welding one hole but the new holes must be placed accordingly. Mine were done on a CNC lathe so they faced them while they were at it. Came out nice but probably just as easy to work some overtime to get some brandy new ones from Richard or Ford Racing. Good Luck

Mike

 

seen it done by hand with a drill , worked , passed the burnout test and went 7.12 in the 1/8 th . Then the posi went away . I have Moser from Richard. Bob

 

i'm with Bigtim01...

i paid 10 bucks each at a bone yard and pulled my own. not hard to do.

good luck with the build!

 

I'm guessing by the time I pay a machine shop to drill and restud my axles I can pull some out of a junkyard and be time and money ahead, assuming they're good.

Anybody doing a 5 lug to 4 lug conversion? Have I got a deal for you.:001_rolleyes:

Tom