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4 on 100mm conversion?


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Converting Hubs to 4x100mm...

 

....lost the original detailed write up when I

upgraded my e-mail software. Here's the basics I

remember:

 

1. Make all modifications to your Subaru hubs at your

own risk.

 

2. I was ultra conservative...had a welder friend

braze the backs of the old studs to the hub/drum.

 

3. Grind the old studs off flush with the wheel mating

surface of the hub/drum.

 

4. Buy studs for a '95 Honda Civic, M12x1.5, I

believe. And they have a smaller shoulder for press

fit than the OEM Subaru studs. So they require a

smaller hole in the hub/drum.

 

5. At a machine shop...A. on a lathe, turn down the

centers/locating bosses to 54mm. The center bore of

OEM Toyota and Mazda wheels (4x100) are 54 mm. Honda

is 56mm so that wheel fits, but you would mount

"lug-centric."

B. On a mill, precisely locate the holes for the new

studs on a 100 mm circle, offset from the old studs by

90 degrees. Bore the new stud holes to the proper

diameter to allow a press fit.

C. Still on a mill....on the insides of the hubs/drums

use an end mill a little larger in diameter than the

head of the new studs to make a flat for the studs to

shoulder up against. Do not remove any more material

depth than necessary to make the flat spots.

 

Note: The front hubs are very hard steel.

 

6. Press the new studs into the hub/drum. We had to

use a hydraulic press to push them into the front hubs

because the steel was too hard for the stud splines to

cut. SO I hope to never have to try to field replace

one of them.

 

7. As mentioned in a previous post, the rear drum

material is very soft and this is apparent when

installing the new studs. Do not use too much pressure

when installing them. Inspect the material after

installation and use good judgment. There is a lot of

metal thickness where the studs are located.

 

8. Get a good coat of primer at least on the machined

surfaces, then re-install the hubs/drums as removed.

 

9. Purchase rims from a local yard or www.tires.com

after researching what width and offset you would

like. I use '95 Protege' 14x5.5 inch. They have a

large positive offset so the tires are completely

under the fender and they were cheap. MAKE SURE THAT

THE RIMS ARE NOT WARPED BEFORE SPENDING A LOT OF TIME

CLEANING AND PAINTING THEM.

 

10. Get tapered seat lug nuts for the M12x1.5 studs. The

taper should be matched to the OEM rim spec. THE RIMS

AND LUG NUTS MUST BE "LUG-CENTRIC" DESIGN, MEANING

THAT THE WHEEL IS CENTERED BY THE LUG NUTS' TAPER.

This is because the front hub will probably not have

enough metal on the hub to center the wheel with its

bore, "hub-centric."

 

11. I run 205/75R14 Cooper Courser SST tires with no lift kit

and minimal scrubbing when locked out in a turn.

www.1010tires.com has a large selection of 14 inch mud

tires.

 

12. When everything is installed test drive with

caution, and after some run time, inspect the

hubs/drums where the new studs are in place for

cracking or other problems.

 

I am sure that I am forgetting some important details

because it's been a couple years. Please post any

questions. Hope this is helpful.

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