To all; now that you have a idea of how HP was juggled and faked for 60+
years (The german DIN HP was always truthful) we come to the idea of just
how much power the little 1725 cc race engine produced (136 bph at the
flywheel (at)7500 rpm in Denver altitude, extrapolates to approx 140+ hp at
sea level)
Now this was honest measurable HP using the race exhaust system, carbs, fan
belt on the water pump...realistic HP.
Compare this output to the honest 71 +- I used to see on stock SV and you
get the picture that we have literally doubled the useable HP of this engine.
This is NOT so shocking as you non technical people may think, for the
following reasons.
1. The stock engine has cam timing for nice low idle as well as mid range
pulling power and a "reasonable" top end hp which gave the car about
98-100mph top speed without OD ( about 92 mph with OD).
2. This was in keeping with the ability of the 1950s chassis design to
handle such speeds as well as the braking system ability to cope as well.
3. The bean counters would not allow a more sophisticated engine design and
there HAD to be a lot of carry over from prior engines so as to keep down
new parts to a min. Also, machining operations related to new designs
were also to be kept to a min.
4. Fuel economy was of some concern (not in the USA) worldwide, due to high
prices where Rootes sold into the third world and in the UK. Therefore
powerful fuel mixtures were not designed in.
5. The Rootes competitors were not making higher performing cars (Triumph,
Alfa and MG mainly) .
6. The engineering staff at Rootes did NOT have any advanced smart guys at
all. They had a rough time just designing parts which would mesh together
and stay working ! The never had a single person who could be described as
being "on top of the subject" of engine outputs.
The guys who lead that field then (and now) were motorcycle engineers !
They get hired by Yamaha, Jaguar, Mercedes, Toyota etc. because they bring
with them explorative minds, new ideas and break new frontiers of
development. Nobody even remotely like that ever got a job at Lord Rootes
joint ! You all know the story of how the Tiger came about, reluctently
allowed by the management people .
So.....I and other race oriented people looked at the Rootes 5 main brg
engine, looked at the alloy head, the twin carbs on a decent manifold and
said.... HEY ! this baby has potential if we do things really right, it
should be able to rev real high and high revs are what make HP!
Hiding inside this engine is a reasonably priced 115-120 TRUE HP and to get
the next 20 HP we have to damn near double that cost of getting the 120 HP.
That last 20 comes real dear fellows. Also when the driver uses it in short
spurts, to make that pass on the track or blow the doors off some Z car or
Vette, you are bringing that max'd engine closer to the time it needs
another set of rings, head job bearings etc. etc. If the driver likes to
play with that power quite frequently, he simple has to bite the bullet and
pay up for more frequent internal overhauls....or...accept lower output and
possibly a Kaboom engine some day!
The above is NOT to say the engine is weak....on the contrary, I ran a full
14 race season between internal freshening up. This included full practice
session on Sat and qualifying Sun mornings, then a 40-45 minute SCCA race
event. Sometimes my car was the ONLY F-prod car to show up and therefore
they bumpped me up into E-Prod class with the big TR4's and Porsche 912 and
356 models. I managed to sit on the pole lots of times and whipped these
usually quicker cars regularly. The engine never failed me in a race.
Ten years later.. my oldest son Rick was running the car in a RMVCC event
at Vale CO. He had passed all the various cars which were in his class,
then he passed ALL the cars in the big engine class and set his sights on a
Ferrari running in first OA. Sure he too was catching the prancing horse
and the crowd was going wild...but when he hung in 2nd gear coming out of a
turn with the V12, he was on the inside of the guy and just had to complete
the pass. Later he thinks he saw the tach coming DOWN and it was then at
8500 ! That cost us a block due to a rod through the main oil gallery.
Stock is sturdy....high outputs make you want to use the power you paid
for, thats just human nature. I thought Corvette engines were really damn
weak due to all the breakage I saw over the years. Now I know whats going
on! The power cries out to the driver to be unleashed and when it is used
frequently...durability has to suffer.
Dick T.
This archive was generated by hypermail 2b30 : Tue Sep 05 2000 - 09:56:18 CDT