I R S ???????

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I R S ???????
dragginbaggins10 avatar
dragginbaggins10
+1y
ok...so my ranger has a rear frame clip with an irs out of a 89 thunder bird super coupe....The problem i'v ran across is that the bolt pattern on the rear irs is 4 1/4 by 5 and the front is 4 1/2 by 5.....both sets of wheels i own are 4 1/2 by 5.....is there away to make the rear bolt pattern a 4 1/2 by 5 bolt pattern.....
TwistedMinis avatar
TwistedMinis
+1y
I've heard people talk about swapping the rear hubs to Cobra hubs or something.

You could probably have them redrilled at a machine shop though, along with the rotors. Or, get a mustang rotor thats the same size with the right bolt pattern.
impounded dakota avatar
impounded dakota
+1y
hmmm, buying two new rims with the 5x4.25 lug pattern seems to be the cheapest option in my mind right now.

you could pay a machinest to plug weld the hub and rotors, and re drill them both to the 5x4.5 pattern, but then you'd have to have that done to your rotors every time you needed to replace them. Or you could just have the hubs done, and do the leg work to find a rotor that matchs all of the dimensions of the stock t-bird rotor, but has the 5x4.5 lug pattern your looking for.

You could order wheels with a fwd offset, and have a set of adapters made, but i don't know how shallow your offset is already, and this will also limit your rim optons, and will be more expensive than just ordering two new rims, as oposed to four.

The last option i have is you could scrap the rear end all together and reinstall a narrowed supra or 300z irs, or something else that has a 5x4.5" lug pattern. Or even going back to the stock straight axel with a 4 link.

So like i said, knowing nothing else about the truck, i'd just say buy two new rims with the right lug pattern to fit the rear end, i'm thinking most people won't catch on, unless you tell them about it first.
WickedBird avatar
WickedBird
+1y
the 5x4.25 bolt pattern of the tbird is a very uncommon bolt pattern if you have not found that out yet. Buying two new wheels may or may not be an option...however it is expensive and pointless.

You have two very simple options. First you can use the hubs from a mustang cobra as mentioned above. The hubs must be from a Cobra though, the non-cobra's have a different spline count. You could then redrill the rotors or get a set that fit. The second option is to redrill the original hubs and rotors, and install new studs and and be done. This can be done easily with a drill press, or a machine shop should be able to do it cheaply. My tbird has been changed to the 5x4.5 pattern as have many others with no problems.
dragginbaggins10 avatar
dragginbaggins10
+1y
what year mustang cobra has simular hubs to those on my 89 irs? Anyone know of good machine shops in ky area? i aready have a new set of 4 1/2 wheels and the truck is a step side so i couldn't run adapters because the tire would eat the bedsides.
sloth avatar
sloth
+1y
You could find an x7 thunderbird or cougar.
lwrnger1 avatar
lwrnger1
+1y
i have an 89 irs in my 2000 ranger re drilled hub to a 5 on 4.5 with stock 98 mustang rotors. havent tryed to do the brake calapers yet good luck.