200 mph 67 Imperial!
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200 mph 67 Imperial!



Quoting Tristan Moore <v-2tmoor@xxxxxxxxxxxxxxxxxxxxxxx>:

> Are you maintaining the 2.94 gears? 
> 
> Yes, As crazy as this may sound, I hope to get the Imp over 200 MPH, and
> I
> don't think anything lower would do that, I may have trouble with the
> 2.94s.
> This is going to be a very strange car.
> 

Interesting!  First of all, let's try to estimate the power required for 200 
mph.  As I recall, the power required for steady state crusing for an Imperial 
at 150 mph was calculated to about 255 hp (at the wheels).  I had made this 
calculation assuming a Cd of 0.45 and frontal area of 2.5 square meters as I 
recall.  Anyway, these numbers are probably close.  For 200 mph, the power 
required would be roughly 255hp*(200/150)^2.7.  The 2.7 power would have been 3 
if the drag was purely aerodynamic, but since some of this is rolling 
resistance, the power is about 2.7 (I can estimate more accurately, but this is 
in the ballpark).  The result is 554 hp at the wheels.  Now, if we assume an 
85% drivetrain efficiency (gearbox and differential loose about 15% of the 
power) the power requirement from the engine (net) would be 652 hp, or about 
twice the power of a stock 440HP engine (remember, we are talking about net 
power).

Now, with the 2.94 gears, if you used the usual tires (235/75R15) 200 mph would 
correspond to about 6600 rpm.  Of course, I doubt you can find tires of this 
size that can handle this type of speed, but you may be able to get something 
equivallent (say 265/60R16, you probably need larger than 15" wheels to keep 
the gearing high).  

Anyway, I doubt the stock heads can give you that much power.  If you used 
heads w/ larger valves (say 2.14 intake and 1.80 exhaust) it is more likely.  
But still, in order to get 650 hp, you would have to rev it a lot more than 
6500 I would guess.  So, you probably need also a huge cam, a single plain 
intake, much higher compression ratio, and possibly lower gearing (no low end 
on this engine, it would be a slug at city speeds).  The only way you may be 
able to get that much power with confidence without having to rev it to 8000 
rpm, and still maintain some low end, is with forced induction.  I have read on 
a MOPAR rag recently of somebody installing a turbocharger on a 440.

Oh yes, if you want to keep the stock speedometer, you can recalibrate it in 
meters per second instead of mph.  89 meters per second is 200 mph!  If a cop 
pulls you over, show him the "70 speed limit" sign and tell him: hey, the units 
were not defined!  I thought the speed limit was 70 meters per second!  I am 
not sure if it will hold in court though.

D^2





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