William Eastman wrote:
>
> In a typical american engine, 10 psi boost would be OK with a 7.5:1
> compression ratio. If care is taken in preparing the head of the TC- round
> all sharp edges, etc- it shoud be OK there provided you use the best gas
> you can get and run to the rich side of the best power mixture.
>
> Concerning the strength of a TC engine. If it were something for which
> replacement parts were readily available, my opinion would be crank it up
> an go for it. However, you are talking 45 years of wear and tear on the
> rotating components already. These components are becoming quiter rare and
> valuable. If it were me, I would feel terrible if I overdid it and threw a
> rod through the block or cracked a head.
>
> >From my knowledge of TC's, 70 or 80 in one of these would be scary
> regardless of the engine. The tires and brakes suck by modern standards.
> In any event, just increasing horsepower will not make the car cruise
> faster. You would have to change the gearing, too. Otherwise you would
> again be risking setting a con rod free through your block.
>
> I do admire the fact that you want to use the TC as a driver. I don't like
> the way the top end of the "collector car" business is going where the cars
> are considered investments or works of art too expensive to risk driving.
> This fall I drove my Corvette down to Kansas and traded it for an MGA. On
> the way down, people scowled at me when I passed them, assuming I was some
> self centerd prick (which I am). On the way back in the A, I got more
> waves and thumbs up than I ever had in my other cars. I can only imagine
> the enjoyment that running a TC down the freeway at 75 mph would bring to
> yourself and to those around you.
>
> Good Luck
> Bill Eastman
> 61 MGA
Mr. William Eastman:
I've been following your comments re performance and technicalities of
combustion closely and again wish to thank you for a thououghly
enjoyable and erudite batch of communiques.
The first car I bought as a callow youth of 16 was an Austin Ulster. I
bought the car solely upon the first word of the
advertisement...SUPERCHARGED. I had to have that car. Up until three
years ago, it was the only supercharged car I had ever owned, and I
suppose that primeval urge had lain dormant for many years. While on a
trip to England, I was able to acquire an original Shorrock supercharger
which I fitted to my 52 TD. This car was totally restored in 1989,
particular attention being paid to the quality of the workmanship
concerning the engine. I requested of the machine shop that the
crankshaft (an original) was Magnafluxed to reveal any defects, and the
flywheel was lightened by about 2 1/4 lbs. The rods were carefully
weighed and the whole balanced accurately. The result was a motor car
which ran (and still does) like a smooth sewing machine. At the same
time that the blower was attached, I also changed the rear axle ratio by
installing an MGA crown wheel and pinion ratio of 4.3:1. I now have an
MG TD which is capable of cruising pleasantly at 70 m.p.h., and in which
I am able to pick my own 'open' gaps in the traffic while driving on the
Interstate highways. Were it not for the apalling condition of
Pennsylvania's roads, (reminiscent of the minor roads in Italy and Spain
shortly after WW2) I have no doubt that more prolonged stages at higher
speeds would be entirely feasible. When cruising at 65 m.p.h., I am
revving at about 3400 r.p.m. which compares well with the 4200 or so
before the ratio change. While I am in full agreement with your
comments concerning the possible dangers of bursting the blocks of what
are now becomming rather rare commodities, I feel that if sufficient
care is given to the reconditioning of the motor in the first instance,
it is not too unrealistic to expect a TC engine to tolerate being blown
within reasonable limits (I get about 6lbs p.s.i. at 5500 r.p.m.). I
would add that I never exceed 5500 r.p.m. purely as a matter of,
hopefully, pragmatic sensibility.
I would recommend anyone with the available fiscal ability and the
desire to 'modernise' their chariot so to do. The resulting performance
enhancement is an excellent safety factor, and, besides, the noise is
wonderful!
As a final note, I reconditioned the distributor at the same time, and,
after the initial running in period of about 1000 miles, during which I
changed the oil and filter 4 times, I adjusted the points. They have
not been touched since, and the car now has 9000 miles on it. Long live
the Prince of Darkness!
Geoff Love, The English Connection.
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