> Could one or more of you data "heads" regurgiate the pound per hp ratios
> of some cars. I would really want to know this info for the Mazda Miata,
> chrome bumper MGB and MGBGT, and rubber bumper MGB and MGBGT.
Here's a table that should help. (Hope everyone has monospace readers. :-)
Miata '67 MGB '75 MGB MGB-GT
Weight 2270 lb 2150 lb 2350 lb 2400 lb
Power[notes] 116 bhp 98 bhp 65 bhp [linear transform]
Torque 103 lb-ft 105 lb-ft 80 lb-ft [see above]
Final Drive 4.1:1 3.9:1 3.9:1 3.9:1
Tire Size 185-60R14 155R14 155R14 165R14
Analysis to follow.
> I want to compare these figures to what my Midget will be when it gets
> the new motor.
Spitfidgets weigh something like 1770 lb (1565 for the Midget plus ~200
for the bumpers & slightly heavier motor). If you can get 100 bhp out
of that 1500 (and not have your rods decide to fly free on their own --
you know about the heating problem that 1500s have in Midget engine
bays, yes?), you will have a very zippy little vehicle.
> If I remember correctly, these data were flying around when someone was
> alittle narked that a Miata left his MGB in the dust at some lights.
This is someone of very little brain, I'm sorry to say. If you put the
Miata engine in an MGB, it would be faster. If you put the Miata
gearing in an MGB with the M.G. engine, it would be faster. If you put
the Miata tires on an MGB (which I've done), it accelerates faster because
the tires are about 2.5" lower, shorter etc; it's comparable to putting
a 4.1 rear axle ratio in the MGB (not to mention the enhancement in
cornering). The published 0-60 times tell the story: the best time I
ever saw published for a stock MGB's acceleration was 11.5 seconds,
and the Miata ranges (depending on who does the test) in stock form
(quiet, Miq) from 8.7 to 9.2 seconds.
Furthermore, there are several things to consider about the MGB's power.
The 98 bhp figure is the highest given for pre-smog MGBs; 1968 MGBs are
typically rated at 92 bhp, and it drops from there. The transformation
is not, in spite of what I say above, strictly linear, as somewhere about
1970-72 there was a change in the way power was measured; the old figures
are the British measurements from the Sixties, while the later ones are
SAE net bhp, typically as much as 10% smaller. The Miata is already
measured at SAE net, so figure that the Miata's power would be rated at
something like 125 or so in 1967's standards (which, BTW, have often been
derided as "horsepower measured at the brochure").
I'm *very* interested in getting The Green Car to run, because the motor
I installed in it has been measured on a dynamometer as putting out 87 bhp
at the wheels; this, the dyno operator says, works out by his conversion
charts to ~110 bhp using the SAE standard.
Oh, and finally, I haven't included weights for the MGB-GT with rubber
bumpers because they were only produced for half a year in the U.S., and
I have seen precisely two in my ten years as an M.G. nerd. The bumpers
weight about 100 lb per end, with all the brackets and braces and fillers
(for those of you who've never taken one apart and looked at the innards,
they're stuffed with metal bars, straps, and braces).
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