> Read this at http://www.grmotorsports.com/boneyard.html and thought the
> rest of you could benefit from it too.
I have a few "problems" with details mentioned in this:
> The next things to look for in a junkyard are transmissions and
> bellhousings. The 1962-'64 cars had a "thin edge" alloy bellhousing which
> will save about 20 pounds over the later steel bellhousings. The 1965 model
> had the thick-edge alloy bellhousing, which is no heavier but even stronger
> then the thin-edge piece.
No question that either "alloy" bellhousing will save a lot of weight; I
think it's over 20 lbs. savings. But those alloy bellhousings really
didn't turn up on very many of even the early Spitfires. They were found
on Herald 948s and on some of the earlier 1200s.
> The best transmissions are the 1975-up single rail
> close-ratio boxes.
Interesting that only the single-rail gearbox is described as close-ratio.
The gear ratios are identical to those found in the three-rail all-synchro
gearbox of 1971-74, and only 1st gear is different from the ratio of that
for the earlier three-rail as found in Herald 1200 and earlier Spitfires.
Then, of course, there is the distinction in number of splines on the
input shaft (10? on the older gearboxes and 20? on the single-rail box),
meaning a clutch disc change is also in order, along with other minor
details like different output flanges....
> Unfortunately, they don't fit the early bellhousing, so
> the best setup is probably a close-ratio box from any Triumph GT6, combined
> with the 1965 alloy bellhousing.
A nice thought, especially as the GT6 boxes (along with earlier Vitesse or
Sports 6 1600 gearboxes) are closer to "true close-ratio" gearsets.
However, this swap also will require some creative swapping around of
clutch pieces or input shafts as well as the bellhousing swap, etc.
> In an effort to get back some performance, a 4.10:1 rear end ratio was
> installed in 1972. While great for racing, this ratio will kill you on the
> street (and in top speed contests) unless you use the overdrive
> transmission.
Seems to me that, on the street it would be a plus; that is, if by "on the
street" one means acceleration contests! :-)
> ...The first thing to do in any street-driven Spitfire is
> to use the 1971-up revised rear spring...
Fine.
> GT6 brakes are considerably bigger
> than those found on a Spitfire and are an easy, bolt-in swap....
Correct, if you remember that by "easy, bolt-in swap" it's best to get the
complete brake/hub/stub axle/upright assembly from the GT6.
> The 1973-up cars have a larger front anti-roll bar (approximately 15/16 inch
> instead of 11/16 inch) which, while not as good as a one-inch aftermarket
> bar, is a cheap junkyard upgrade.
And it's a: pretty much vital to do this if you've converted to a
swing-spring, and b: that fatter bar first came in 1971 with the
swing-spring, NOT 1973. The big deal about the 1973 models was the 2"
wider rear track, by virtue of drive axles 1" longer per side.
> The later 1977-up cars have a smaller 13.5-inch steering wheel which makes
> the car easier to steer.
Spitfire wheels got progressively smaller over the years, having started
out at either 15" or 16" (sorry, can't remember which). But ISTR that the
steering wheel size was down to around 13-13.5" beginning with the 1973's.
As for easier to steer? Well, a smaller wheel gives you more room in a
cramped cockpit and yes your hands won't move as far, but you lose the
leverage of a bigger-diameter wheel, so we need to define "easier to
steer"! :-)
> The Spitfire weighed less than 1500 pounds when it was first introduced, but
> the weight went up to over 1800 pounds by 1980.
Again I'd have to double-check all this, but I don't recall even the
earliest Spitfires weighing less than about 1568 lb. dry and around 1620
"curb weight". I know the last of the 1979-80 Federal models had gotten
much heavier, mostly due to the bumper supports and related mounts.
I'll leave any constructive criticism on the TR4-6 information to those
better versed in same.
--Andy
* * * * * * * * * * * * * * * * * * * * * * *
* Andrew Mace, President and *
* 10/Herald/Vitesse (Sports 6) Consultant *
* Vintage Triumph Register <www.vtr.org> *
* amace@unix2.nysed.gov *
* * * * * * * * * * * * * * * * * * * * * * *
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