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RE: Engine Swaps Again (longish--with tables!!)

To: spitfires@autox.team.net
Subject: RE: Engine Swaps Again (longish--with tables!!)
From: Mike Welch <mikew@turbopower.com>
Date: Tue, 20 Apr 1999 16:38:19 -0600
Not necessarily, it has very good low end power, and it carries it through
to higher revs (I don't have a tach on it, so I can't say where it peaks).
I ran a little experiment using the CarTest shareware program, it actually
looks pretty good.  I took the Jeep Cherokee data, and modified the body to
match the '80 Spitfire specs.  BTW, if anyone is interested, I can put
CarTest on my web site for you to download.

                            SPITFIRE W/JEEP ENGINE
                            ----------------------
 
                              CAR SPECIFICATIONS
 
                     Engine Displacement:     3960 cc.   
                     Engine Location:        FRONT       
                     Engine Type:           NORMAL       
                     Engine Max Horsepower:    190 bhp   
                                         @:   4750 rpm   
                     Engine Torque:            225 lb-ft 
                                 @:           4000 rpm   
                     Compression Ratio:        9.2 :1    
                     Maximum engine speed:    5250 rpm   
                     Start Engine Speed:      3900 rpm   
                     with Clutch:     BRAKE TORQUE       
                     Transmission Type:  AUTOMATIC       
                     Number of Gears:            4       
                     Gear Ratio 1st:          2.80 :1    
                     Gear Ratio 2nd:          1.53 :1    
                     Gear Ratio 3rd:          1.00 :1    
                     Gear Ratio 4th:          0.75 :1    
                     Gear Ratio 5th:               :1    
                     Gear Ratio 6th:               :1    
                     Final drive ratio:       3.55 :1    
                     Driving wheels:           ALL       
                     Car test weight:         1980 lb.   
                     % weight on front wheels:  52 %     
                     Wheelbase:               83.0 in.   
                     Tire section width:       155 mm.   
                     Tire circumference:      5.92 ft.   
                     Wheel diameter:            13 in.   
                     Tire profile:              70 %     
                     Coefficient of drag:     0.42       
                     Frontal area:                 sq.ft.
                     Overall height:          45.6 in.   
                     Overall width:           58.5 in.   
                     Ground clearance:         5.0 in.   

                                                                          
                            SPITFIRE W/JEEP ENGINE
                            ----------------------
 
                              GENERAL PARAMETERS
 
              Air Temperature:                        65 deg. F.
              Barometric Pressure:                 29.38 in. Hg.
              Relative Humidity:                      55 %      
              Elevation above Reference:               0 ft.    
              Headwind (+), Tailwind (-):              0 mph    
              Road Grade (+=Ascend, -=Descend):        0 %      
              Shift Time, Manual:                   0.50 sec.   
              Shift Time, Auto:                     0.30 sec.   
              Engage Time, Manual:                  0.20 sec.   
              Engage Time, Auto:                    0.10 sec.   
              Clutch Slip Max. Time, Manual:        5.00 sec.   
              Brake Release Time at Start, Auto:    0.10 sec.   
              Trans. Engage Method-Lin,Prog,Regr:      R        
              Shift@O=Optim,R=Redline,D=Driver,P=Prog: O        
              Engine Free Decel Rate:               2000 rpm/sec
              Engine Bog Down Decel Rate:           4000 rpm/sec
              Engine Wheelspin Decel Rate, Manual:   500 rpm/sec
              Engine Clutch Slip Decel Rate, Man.:   250 rpm/sec
              Engine Trans. Slip Accel Rate, Auto:   750 rpm/sec
              Engine Wheelspin Accel Rate, Auto:     250 rpm/sec
              Max. Coefficient of Static Friction:  1.00        
              Max. Coefficient of Kinetic Friction: 0.85        
              Coefficient of Rolling Resistance:   0.013        
              Tire Expansion Factor:               0.020 %/mph  
              Hot Tire Pressure:                      35 p.s.i. 
              Tire Tread to Section Width Ratio:    90.0 %      
              Wheel and Tire Weight:                  45 lb.    
              Minimum Engine Speed:                  700 rpm    
              Zero h.p. Engine Speed:                600 rpm    
              Turbo Start Speed:                    3000 rpm    
              Max. Torque Conv. Slack Until, Auto:  2000 rpm    
              Low Max. Brake Torque Speed, Auto:    2000 rpm    
              Time Increment:                       0.05 sec.   
              Start Time after Car Moves:           1.00 ft.    
              Mechanical Losses-Auxiliaries:        2.00 %      
              Mechanical Losses-Manual Trans.:      6.00 %      
              Mechanical Losses-Auto Trans.:        8.00 %      
              Mechanical Losses-Differential:       4.00 %      
              Mechanical Losses-Axles & Shafts:     5.00 %      
              Mechanical Losses-Torque Converter:   3.00 %      
              Max. Clutch Slip Losses, Manual:     10.00 %      
              Max. Trans. Slip Losses, Auto:       15.00 %      
              Max. Torq. Conv. Torque Multiplier:   2.25        
              Effective Engine Radius:               3.0 in.    
              Drive Shaft Radius:                    1.0 in.    
              Center of Gravity from bottom:        30.0 %      
              Graphics Aspect Ratio (EGA):          0.75        
              Graphics Aspect Ratio (VGA):          1.00        
              Sound Effects (Y=Yes, N=No):             Y        

                                                                          
                            SPITFIRE W/JEEP ENGINE
                            ----------------------
 
                     STANDING START ACCELERATION RESULTS
 
                      Starting vehicle speed:    0 mph 
                      Starting engine speed:  3900 rpm 
                      Starting gear:           1st     
                                 
                      Optimum Shift Points:            
                      1st      5250 rpm   @     35 mph 
                      2nd      5250 rpm   @     65 mph 
                      3rd      5130 rpm   @     98 mph 
 
                      Time to Speed:                   
                       0- 30 mph............   1.4 sec.
                       0- 40 mph............   2.6 sec.
                       0- 50 mph............   3.7 sec.
                       0- 60 mph............   4.7 sec.
                       0- 70 mph............   6.7 sec.
                       0- 80 mph............   8.5 sec.
                       0- 90 mph............  10.4 sec.
                       0-100 mph............  13.5 sec.
 
                      Time to Distance:                
                       0- 100 ft............   2.7 sec.
                       0- 500 ft............   7.3 sec.
                       0-1320 ft.(1/4 mile).  13.6 sec.
                                          @  100.2 mph 
 
                      Top Speed............. 134.7 mph 



Mike Welch
'68 +/- Spitfire MkIII
'60 Jaguar MkII
http://home.turbopower.com/~mikew 

-----Original Message-----
From: Dr. Faustus [mailto:faustus@inconnect.com]
Sent: Tuesday, April 20, 1999 3:24 PM
To: Mike Welch
Cc: spitfires@autox.team.net
Subject: RE: Engine Swaps Again



On Tue, 20 Apr 1999, Mike Welch wrote:

> 
> I haven't taken the tape measure out, but the engine schematics fit in the
> frame schematics (yes, they were at the same scale<g>)  I lined up the
> engine mounts and the frame mounts, and the top of the engine was about
1-2"
> above the hood (nothing a hood scoop wouldn't cover).  The tranny was in
> about the right place, with the shift lever about 2" behind the stock Spit
> lever.  Since I haven't done the swap (except in my head<g>), all I'll say
> is the AutoCAD drawing looks like it will fit.  (if my '89 Cherokee is
> wrecked and the engine is still good, I'll see if it will really fit<g>)
> 
> Mike Welch (TurboPower Software) 

I might be wrong, but I thought the Jeep engine was a torque engine.  Not
a quick wrapping run through the revs engine.  More suited to moving
slowly while climbing over anything.

Andy L.
'70 Spit

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