SteenH

I'm absolutely beyond confused right now, any help is appreciated here. Little backstory below.

I found a seasoned strange 12 bolt on the ls1tech classifieds, contacted the fella and low balled him. weeks later I received a message and he was ready to sell for the right price (I couldn't refuse). So I packed up, grabbed the girlfriend and headed 21 hours southeast to pickup this thing.

I get it in the shop, get it cleaned up, painted and I'm getting excited for the install. I contact strange to try and get some new bearings / wedding rings sent to me (stock backing plates had to be put on). It originally had the strange race brakes on it. Strange tells me I can't use the stock backing plates with the "strange race axles" because the proper bearing isn't available. Alright, I decide I'm going to order the backing plate spacer, and chop my backing plates enough to slide them over the axles. (No bearing removal needed) glad I got that figured out.

I'm out in the shop today and decide to pop the axles in and do a axle face to axle face measurement (to make sure it is in fact narrowed 2 inches per side like I was told)
I get a measurement of 61" face to face.
I decide to measure an old 10 bolt I have laying around, 64" axle face to axle face... This stuns me because when I measure the strange housing end to housing end I get 55 1/2" (stock 10 bolt 59 1/2" backing plate mount to backing plate mount)

This would leave me to believe the housing is in fact 2" shorter per side, but when I measure axle face to axle face I'm shown only 1 1/2 shorter per side, why is this?
Is it something to do with the fact that it has the race axles? I had planned on eventually ordering some "street" axles but running the race axles for the time being. I'm baffled. I had planned on using the 15x10 with 5.5 bs wheels that I had purchased from the same guy, but finding out what I just did this will leave the wheels sticking out 1/2 inch per side over stock.

I guess my question is... What measurement dictates the rear end width, housing end or axle face? (which could depend on bearing spacing)

Thank you to anyone who continued to read and has any input on the subject.

MidwestChassis

iTrader: (5)

What year was the car that the 12bolt came out of?

SteenH

LT1 Camaro like a 95 or so. Initially when I measured the axle face to face I assumed it was a third gen rear.

01ssreda4

iTrader: (96)

How are you exactly measuring width when you dont even have bearings to locate the axle? I'm curious cause it know it may be hard to gauge.

And holy smokes you drove a long way to get that thing.

SteenH

Not sure what you meant but as far as I know the axles are sitting where they would.

Here's the car the 12 bolt came out of. The guy I got it from as far as I know bought it to part it out. So he doesn't know either. Maybe someone knows the car, and can tell me something. Lol

01ssreda4

iTrader: (96)

Oh it has bearings on it? Misread. As far as that car pic its hard to tell but that looks like a -2 offset wheel. Usually its pretty easy to tell by the lip....I mean very obviously it's not stock backspacing. I can see your confusion though as it would seem that the measurments dont add up. Do you have your rear wheels already?

SteenH

No, I had planned on using some 15x10 race stars with 5.5 back spacing for the time being. and in the near future ordering myself some champion bead locks with 6" back spacing (to bring it in 1/2" each side) which in theory works with what I have right now as well.

I would assume that because housing end to housing end its 4" shorter total it's really 2" per side (for when I do order axles) I'm guessing it's something to do with the current axle/ bearing setup. This leads me to worry about the brakes not being in the right location. The fun of buying used stuff.

01ssreda4

iTrader: (96)

I have the S/S axles in mine. When I originally assembled it there was a spacer that goes before the bearing, obviously it locates the bearing and therefore locates the axle width. Maybe thats part of the equation.

drain89

iTrader: (13)

Either a custom, or something weird strange did. They did weird **** from time to time. I have a strange 12 bolt that for some weird reason they made with 2 5/8" axle tubes back in 05. I know the ones made for third gen f-bodies were 1.5" narrower per side. Not a bad thing really. You can buy good wheel spacers and upgrade the wheel studs on them and the axles for now and it'll be plenty strong. THEN when you want to do wheels you can go with less backspacing and have a much deeper dish in the rear which looks better. That's the route I chose.

01ssreda4

iTrader: (96)

The first gen strange 12 bolts had smaller axle tubes from what I gather.

SteenH

Sorry for the bump, just thought I'd clarify *for future readers* that the axles having the different spacing was pretty much irrelevant due to the stock ls1 brakes not being a fixed caliper.
Rear is in, issue free. Ended up just notching the stock backing plates to get them on and off the axles without pressing on/off the bearings aswell.
Still using a 15x10, 5.5bs wheel with 28x12.5 Et street (28x10.5 et drags) tucked.