An Engine Power Calculator    Mr Ginger 1993
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Version 1.00 (29-May-93)

Horse Power is :
-----------

b.h.p = ( torque * revolutions ) / time

torque is the twisting force that turns the wheels . It is
measured in pounds per foot . 33,000 lb/minute is one
whole horsepower . This was devised by J.Watt using strong
Dray horses , and was understandable at the time . Power is
the 'rate of work done' . Engine speed is in revolutions
per minute .

Brake Mean Effective Pressure 
-----------------------------

b.m.e.p. = ( b.h.p. * 13,000 ) / ( Capacity * revs. ) 

This is useful as it calculates an average of 
cylinder pressures .

As an example 
-------------

1.025 Litre engine 
torque 38 lb at 5,700 r.p.m
= 49 b.h.p 
=111 b.m.e.p  

0.875cc version , 
torque 55 lb at 4,700 r.p.m
= 44 b.h.p 
=141 b.m.e.p  

The Horse Power alone does not reveal the diffrence in the
state of tune . But the B.M.E.P does spot the diffrence .
Horse Power alone is misleading . 

5.7 Litre Yank V8
torque 230 lb's at 4,700 r.p.m
= 205 b.h.p
=  99 b.m.e.p

5.2 Litre European stock !
torque 380 lb's at 4,800 r.p.m
= 348 b.h.p
= 165 b.m.e.p

To tune the first example it would be hard to fail ,
the second example would empty the bank balance .

Last but not least

Hillman Imp 

0.998cc version , 
torque 7O's lb at 8,250 r.p.m
= 120 b.h.p 
= 190 b.m.e.p



Reffrence
---------

Buy    =Performance Tuning in Theory & Pratice 
Author =A.Graham Bell
ISBN   =0 85429 275 6'

 Mr Ginger 1993 
