Gbody drum to drum options?

I used a HPMotorsports kit made to put a 12-bolt under a G-body on my 86 GN. Only instead of a 12-bolt I used a 8.5 from a 72 Skylark. It has its advantages. Because the tubes are 1.5" longer per side I was able to stuff 10" wide wheels up under the sheet metal with out notching the frame. I just had the wheels made with a 6.250" BS. Because of the way the wheel shells are made you cant use a 10" on the stock axle. This added a lot to the rear track and the car handles like its on rails with some sticky rubber on it.This rear is the GM B-O style which means it doesn't use C-clips. The bearings are pressed on like a 9" Ford. No need for C-clip eliminators. It also has the common GM 4 bolt flange which means I can bolt on just about any factory brake. Right now I'm running 11" drums from a 77 ElCamino with some stock car shoes. I can power brake the car well past 20 pounds with out the rear tires breaking loose. Maybe in the future I'll put some discs on it.
 
Thanks for the response!!! That is EXACTLY what I'm talking about!!!! I'd be fine with the 12 bolt kit or do you advise using an 8.5? All those advantages you spoke of are from using the 8.5 or the kit regardless of 8.5/12bolt?

Thanks again!!!! 10 inches and 4.5 or 5.25 BS would work on that set up (those are the only backspaces the wheels I'm looking at come in)>??

Thanks again!
 
seems like a lot of work and $$$ to spend to only gain bolt in axles.
as far as fitting wider wheels with different axles- the same width wheel will fit in the stock wheelwells no matter how long the axle is. if a 5" backspace fits with the stock axle, then a 6.5" backspace will fit with an axle that's 1.5" longer.
i'd spend the same amount of $$ and just get 9" Ford axle flanges welded on your stock housing that allow you to use any GM rear brake setups. get a stronger set of aftermarket axles with Ford bearings, and go play without worrying about breaking axles.
 
seems like a lot of work and $$$ to spend to only gain bolt in axles.
as far as fitting wider wheels with different axles- the same width wheel will fit in the stock wheelwells no matter how long the axle is. if a 5" backspace fits with the stock axle, then a 6.5" backspace will fit with an axle that's 1.5" longer.
i'd spend the same amount of $$ and just get 9" Ford axle flanges welded on your stock housing that allow you to use any GM rear brake setups. get a stronger set of aftermarket axles with Ford bearings, and go play without worrying about breaking axles.

The reason I did it was to find a cheaper alternative to the stock 8.5. I did this over 10 years ago. At that time a used 8.5 was fetching $1000 or more. Its the same amount of work as stuffing any non stock axle up in there. I just happened to have that axle from a parts car and I knew the guys at HPM so the parts were cheap from a monetary POV.Even with the wheels I have about $600 wrapped up in the conversion. My GN was built to conform to stock appearing rules. Thats the only reason I hung drums on the back. It just depends on what you're building the car for. If I was building a stock suspensioned drag car capable of 9 second ETs I would have done it differently. I'm quite satisfied with how well my pick of parts worked out and I've used it to my advantage.

As far as going with a 12 bolt I'd say yes if you can find one. They aint the cheapest axle to build so it might be cost effective to go with a 8.5 if you dont need the strength. Lots of 10 second cars in the 10's with the stock stuff anyway. Here's a pic of a rear shot of my GN to get an idea of how clean it looks wide some rubber under the sheet metal.:cool:
 

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No, they are the stock GN steels widened. 15X10 with a 6 1/4 BS on the rear. The usuall 15X8 with a 4"BS on the front. The car sits at least 3" lower all the way around from cut down springs. I could have lowered it more but I stopped when I could no longer slide the floor jack under the frame rails.
 
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