> I've been musing about the Spit' and was wondering what other engines
> would fit in there? ('75 squaretail) rather than going through the
> hassle of rebuilding the 1500 into a juicy motor (re: Dennis and his
> disapointment at the low max. poss. hp due to cooling problems) is it
> possible to pop a bigger motor in?? As soon a s the Midget is finished
> I want to get started ion the Spit'.
Well, far be it from *me* to admit the superiority of a Triumph product
to an M.G. product in ANY way :-), but there's some evidence that part
of the problem that Dennis is experiencing is limited to putting the
1500 into the Midget's engine bay.
If you look at the Midget's bay, you'll see that the 1500 is a very
tight fit, while there's a lot more room and much more air circulation
in the Spitfire. (Part of this comes from their design; the Midget
was BMC's first unibody sports car when it was the Sprite, so they
overengineered some aspects of it simply because they didn't know
what they could get away with apropos rigidity and longevity. This,
however, is one reason there are still so many Bugeye Sprites on the
road; they erred on the side of long life.) There's a common, known
bug in 1500-engined Midgets, in which a connecting rod -- typically
the #2 for reasons probably having to do with localized temperatures --
seizes on the crank, breaks, and blows a hole in the side of the block.
This, to the knowledge of most of the Spitfire experts on this list,
is NOT a known bug with the Spit implementation of the 1500. The general
explanation is that the more open bonnet in the Spitfire permits greater
air circulation and therefore better cooling of the surface, while the
restricted air flow (which hadn't been a problem on the smaller and
possibly better-cooled A Series engines) caused Midget failures. (Either
that or the poor M.G. self-destructs out of shame. :-)
This would tie in with Dennis' research indicating that the 1500 is
already marginal in its ability to shed excess BTUs (hey, if they're
really British thermal units, they should just leak out!). It's
already close to its operational limits in the Spitfire, so if you
change the limit even slightly -- either by increasing its performance
or by restricting ambient air exchange -- you blow up.
> Are there any simple 'drop-ins' that would work?? I'd rather it was
> another british motor...not a jap./germ. thing. Perhaps a TR7 engine???
> I have no idea about the size of these etc. Has anybody out there
> done this (with any engine).
Someone on this list years ago had put a 7 motor and 5-speed, I think,
into a Spitfire. Of course, I heard that on the Miata mailing list,
someone is selling a complete Miata drivetrain -- engine, transmission,
driveshaft, diff, halfshafts and all the way out to the rear disc brakes --
for only $2995. Such a deal! :-)
--Scott
|