Hi all,
At 11:20 AM 7/25/00 -0400, Jeff Snook wrote:
>We are also looking into the Ford set-up
>that John Harkness is using. SVRAs tech and originality guru Jack Woehlre
>has endorsed this fix since it doesn't change the track of the car and is
>invisible form the outside of the car. AND it is a major safety
>improvement!
>
>OK, who's going to race me to the junk yard for those old ford rear ends!!!
I remember that John H. and I talked about his conversion when he was
setting it up, but I forget what he ended up with. However, for those who
might be interested (and I did get some off-list requests), here is my
solution. Note that this is on an autocross car, so I am free to use any
live axle that I want, and that I have converted to rear disc brakes. I
assume that the vintage race organizations would require drum brakes
at the rear, and you'd have to figure out how to do that. One of the nice
things about this conversion (in addition to using all brand new parts) is
that you can specify the track width, so that it looks correct from outside
the car. Anyway, here's what I wrote up earlier:
===================================================
Speedway Rear axle conversion:
>Could you give me the scoop on what you did?
Sure thing. I'm using a Speedway Engineering axle housing (purchased
through the local Speedway East distributor - Townsend Racing). It
is what they call a Full Floating Mini-Stock rear. There are two
"standard" bolt patterns for this rear, one of which is 4 on a 4.5"
bolt circle - the same as the TR! Guess which hubs I used? These
hubs are available in aluminum or in steel; I chose to use the aluminum
hubs. Basically, I just measured the hub flange to hub flange distance
and told them that "I need a rear end that's this big" They sized the
axles to fit that housing. If you're going to stick with the drum brakes
at the rear, you'll probably have to make an adaptor plate - I was
planning to go to discs on the rear anyway, so I just bought a caliper
mounting bracket and welded that on. I got a brake disc that was
about the same size as the one on the front (I think the rear is
10 1/2"). With the Speedway rear, you have your choice of center
sections, and I decided to go with the 8" Ford since it was the
smallest and lightest (and easiest to find) of the alternatives.
The 8" rear is not as well supported with gear ratios as the 9",
but both a 4.11 and a 4.62 are available as I recall (I'm using a
4.62 with the O/D). I got my complete center section with Detroit
Locker and the ring and pinion already set up from Reider Racing.
Oh, and the axle tube is a 3" tube instead of the 2" or so tube that
Triumph used, so I had to get leaf spring brackets (I used bolt on
ones, but weld-on ones are readily available) for the axle housing.
Since that makes the U-bolt spacing too wide for the Triumph spring
plate under the leaf spring, I had to make those up, too. I
basically just copied the dimensions from the old one and enlarged
the U-bolt spacing. If you decide to do it, I've still got the
drawings for that piece on the computer. The thicker axle tube
effectively lowers the car an additional 1/2" or so. Lessee, I also
had to make up new brackets to mount my axle locating bars (Panhard
tube equivalents) to the thicker tube. I also had to have a new
end put on the driveshaft to take the Ford u-joint. I got the
driveshaft balanced at the same time. I think that's about it,
but I've probably forgotten something. I can supply phone numbers
and addresses for various suppliers if you need that info (and I can
probably even find part numbers if I dare look at my receipts...)
===================================================
I'll be happy to provide further details for anyone who's interested.
John Lye
rjl6n@Virginia.edu
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