Saabscene Saab Forum - Saab Technical Information Resource banner
1 - 20 of 32 Posts

·
Registered
Joined
·
753 Posts
Where's the best place to go and try that? I found the German Autobahns adequate for finding the Vmax of my Aero.

I wonder how much Millbrook costs to hire...

I calculated that the upgrade of my Aero's power from 225 to 282 should raise the max speed from 149 to between 161 and 167 depending on whether the drag is an inverse square or cube of speed (or somewhere in between). All gets a bit complex...
 

·
Registered
Joined
·
14,305 Posts
Depends on your power curve/gearing... revs alone aren't necessarily the answer, as peak power (which is what is needed for max speed) normally occurs below peak revs.

If you need, say, 300hp to achieve 160mph then you obviously must be at a point in the rev range where the output equals or exceeds that amount.

For most B234s, peak power is circa 5600rpm. Thus I'd guess that most would be 5.6 x 28= 157 max. Higher powered ones will probably make mid 160s.

On revs alone in my case with a 4.05 final drive and a 6400 max, it would be 160mph.
 

·
Registered
Joined
·
1,597 Posts
Out of interest - what's the drag co-effient of the 9k CS and how does it compare with other cars?
To me it looks like it has 'OK' drag but I don't think it is anything special on that front = crazy top speeds get very hard to achieve.
 

·
Registered
Joined
·
132 Posts
Originally posted by faero:
[qb]Out of interest - what's the drag co-effient of the 9k CS and how does it compare with other cars?
To me it looks like it has 'OK' drag but I don't think it is anything special on that front = crazy top speeds get very hard to achieve. [/qb][/b]
I think it's about 0.34
 

·
Registered
Joined
·
548 Posts
With the B234R gearbox and its long final drive, the 149mph top speed is about 5000rpm, whereas peak power is at 5500.

Extra power should bring Vmax revs closer to peak power revs...

Sevenman,

Since our Autobahn match-up in 2003 (two identical Aeros, empty straight road, 50mph in 5th, WOT for a minute...) I have changed my specs to Maptun3 and the 4th and 5th gear accel is much better, you will love it.

With stock gearing and wheels/tyres you will quickly see 5500 rpm in 5th, and the Aero has more to give if your nerves or the road can take it. I have seen 5700+ which has to be > 155mph to judge from the new cars receeding into the backround, but it is not a good idea to look anywhere but a mile down the road at that speed.

If you do significant mods you almost have to do a proper Autobahn road trip to see what it can do.
A5 south of Frankfurt late at night is 3 lanes each way, lots of flat and straight...come on, you know you need to do it!
 

·
Registered
Joined
·
8,948 Posts
And a set of results from cartest v4.5 (it also does pretty pictures...)

Code:
                            SAAB 9000 AERO 1993
                             -------------------
 
                              CAR SPECIFICATIONS
 
                     Engine Displacement:     2290 cc.   
                     Engine Location:        FRONT       
                     Engine Type:            TURBO       
                     Engine Max Horsepower:    285 bhp   
                                         @:   5300 rpm   
                     Engine Torque:            312 lb-ft 
                                 @:           3400 rpm   
                     Compression Ratio:        9.3 :1    
                     Maximum engine speed:    6200 rpm   
                     Start Engine Speed:      1400 rpm   
                     with Clutch:             DUMP       
                     Transmission Type:     MANUAL       
                     Number of Gears:            5       
                     Gear Ratio 1st:          3.38 :1    
                     Gear Ratio 2nd:          1.76 :1    
                     Gear Ratio 3rd:          1.18 :1    
                     Gear Ratio 4th:          0.89 :1    
                     Gear Ratio 5th:          0.70 :1    
                     Gear Ratio 6th:               :1    
                     Final drive ratio:       3.61 :1    
                     Driving wheels:         FRONT       
                     Car test weight:         2970 lb.   
                     % weight on front wheels:  60 %     
                     Wheelbase:              105.1 in.   
                     Tire section width:       215 mm.   
                     Tire circumference:      6.15 ft.   
                     Wheel diameter:            17 in.   
                     Tire profile:              45 %     
                     Coefficient of drag:     0.29       
                     Frontal area:                 sq.ft.
                     Overall height:          55.7 in.   
                     Overall width:           69.4 in.   
                     Ground clearance:         5.5 in.   
                                                                           
                             SAAB 9000 AERO 1993
                             -------------------
 
                           CAR-SPECIFIC 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        
              [email protected]=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:                      40 p.s.i. 
              Tire Tread to Section Width Ratio:    50.0 %      
              Wheel and Tire Weight:                  25 lb.    
              Minimum Engine Speed:                  700 rpm    
              Zero h.p. Engine Speed:                600 rpm    
              Turbo Start Speed:                    1500 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        
                                                                           
                             SAAB 9000 AERO 1993
                             -------------------
 
                           CAR-SPECIFIC PARAMETERS
 
              Engine Power @   500 rpm:                  hp     
              Engine Power @  1000 rpm:                  hp     
              Engine Power @  1500 rpm:               50 hp     
              Engine Power @  2000 rpm:               80 hp     
              Engine Power @  2500 rpm:              120 hp     
              Engine Power @  3000 rpm:              168 hp     
              Engine Power @  3500 rpm:              202 hp     
              Engine Power @  4000 rpm:              236 hp     
              Engine Power @  4500 rpm:              264 hp     
              Engine Power @  5000 rpm:              282 hp     
              Engine Power @  5500 rpm:              279 hp     
              Engine Power @  6000 rpm:              270 hp     
              Engine Power @  6500 rpm:              265 hp     
              Engine Power @  7000 rpm:                  hp     
              Engine Power @  7500 rpm:                  hp     
              Engine Power @  8000 rpm:                  hp     
              Engine Power @  8500 rpm:                  hp     
              Engine Power @  9000 rpm:                  hp     
              Engine Power @  9500 rpm:                  hp     
              Engine Power @ 10000 rpm:                  hp     
              Programmed 1-2 Shift:                      rpm    
              Programmed 2-3 Shift:                      rpm    
              Programmed 3-4 Shift:                      rpm    
              Programmed 4-5 Shift:                      rpm    
              Programmed 5-6 Shift:                      rpm    
              Defined Lateral Acceleration:              G's    
                                                                           
                             SAAB 9000 AERO 1993
                             -------------------
 
                     STANDING START ACCELERATION RESULTS
 
                      Starting vehicle speed:    0 mph 
                      Starting engine speed:  1400 rpm 
                      Starting gear:           1st     
                                 
                      Optimum Shift Points:            
                      1st      6200 rpm   @     35 mph 
                      2nd      6200 rpm   @     68 mph 
                      3rd      5800 rpm   @     96 mph 
                      4th      5670 rpm   @    125 mph 
 
                      Time to Speed:                   
                       0- 30 mph............   1.6 sec.
                       0- 40 mph............   3.0 sec.
                       0- 50 mph............   4.1 sec.
                       0- 60 mph............   5.0 sec.
                       0- 70 mph............   6.8 sec.
                       0- 80 mph............   8.2 sec.
                       0- 90 mph............   9.7 sec.
                       0-100 mph............  12.3 sec.
 
                      Time to Distance:                
                       0- 100 ft............   2.9 sec.
                       0- 500 ft............   7.5 sec.
                       0-1320 ft.(1/4 mile).  13.5 sec.
                                          @  105.9 mph 
 
                      Top Speed............. 163.5 mph 

 

·
Registered
Joined
·
8,948 Posts
Rough and ready ylee plat with 430bhp @ 6000 and [email protected] 4000

Now if I had the bhp at each 500rpm break...


Code:
                            SAAB 9000 AERO 1993
                             -------------------
 
                              CAR SPECIFICATIONS
 
                     Engine Displacement:     2290 cc.   
                     Engine Location:        FRONT       
                     Engine Type:            TURBO       
                     Engine Max Horsepower:    430 bhp   
                                         @:   6000 rpm   
                     Engine Torque:            450 lb-ft 
                                 @:           4000 rpm   
                     Compression Ratio:        9.3 :1    
                     Maximum engine speed:    7000 rpm   
                     Start Engine Speed:      1500 rpm   
                     with Clutch:             DUMP       
                     Transmission Type:     MANUAL       
                     Number of Gears:            5       
                     Gear Ratio 1st:          3.38 :1    
                     Gear Ratio 2nd:          1.76 :1    
                     Gear Ratio 3rd:          1.18 :1    
                     Gear Ratio 4th:          0.89 :1    
                     Gear Ratio 5th:          0.70 :1    
                     Gear Ratio 6th:               :1    
                     Final drive ratio:       3.61 :1    
                     Driving wheels:         FRONT       
                     Car test weight:         2970 lb.   
                     % weight on front wheels:  60 %     
                     Wheelbase:              105.1 in.   
                     Tire section width:       215 mm.   
                     Tire circumference:      6.15 ft.   
                     Wheel diameter:            17 in.   
                     Tire profile:              45 %     
                     Coefficient of drag:     0.29       
                     Frontal area:                 sq.ft.
                     Overall height:          55.7 in.   
                     Overall width:           69.4 in.   
                     Ground clearance:         5.0 in.   
                                                                           
                             SAAB 9000 AERO 1993
                             -------------------
 
                           CAR-SPECIFIC 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        
              [email protected]=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:                      40 p.s.i. 
              Tire Tread to Section Width Ratio:    50.0 %      
              Wheel and Tire Weight:                  25 lb.    
              Minimum Engine Speed:                  700 rpm    
              Zero h.p. Engine Speed:                600 rpm    
              Turbo Start Speed:                    1500 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        
                                                                           
                             SAAB 9000 AERO 1993
                             -------------------
 
                           CAR-SPECIFIC PARAMETERS
 
              Engine Power @   500 rpm:                  hp     
              Engine Power @  1000 rpm:                  hp     
              Engine Power @  1500 rpm:                  hp     
              Engine Power @  2000 rpm:                  hp     
              Engine Power @  2500 rpm:                  hp     
              Engine Power @  3000 rpm:                  hp     
              Engine Power @  3500 rpm:                  hp     
              Engine Power @  4000 rpm:                  hp     
              Engine Power @  4500 rpm:                  hp     
              Engine Power @  5000 rpm:                  hp     
              Engine Power @  5500 rpm:                  hp     
              Engine Power @  6000 rpm:                  hp     
              Engine Power @  6500 rpm:                  hp     
              Engine Power @  7000 rpm:                  hp     
              Engine Power @  7500 rpm:                  hp     
              Engine Power @  8000 rpm:                  hp     
              Engine Power @  8500 rpm:                  hp     
              Engine Power @  9000 rpm:                  hp     
              Engine Power @  9500 rpm:                  hp     
              Engine Power @ 10000 rpm:                  hp     
              Programmed 1-2 Shift:                      rpm    
              Programmed 2-3 Shift:                      rpm    
              Programmed 3-4 Shift:                      rpm    
              Programmed 4-5 Shift:                      rpm    
              Programmed 5-6 Shift:                      rpm    
              Defined Lateral Acceleration:              G's    
                                                                           
                             SAAB 9000 AERO 1993
                             -------------------
 
                     STANDING START ACCELERATION RESULTS
 
                      Starting vehicle speed:    0 mph 
                      Starting engine speed:  1500 rpm 
                      Starting gear:           1st     
                                 
                      Optimum Shift Points:            
                      1st      7000 rpm   @     40 mph 
                      2nd      6700 rpm   @     74 mph 
                      3rd      6400 rpm   @    106 mph 
                      4th      6290 rpm   @    139 mph 
 
                      Time to Speed:                   
                       0- 30 mph............   1.3 sec.
                       0- 40 mph............   1.6 sec.
                       0- 50 mph............   3.3 sec.
                       0- 60 mph............   4.3 sec.
                       0- 70 mph............   5.0 sec.
                       0- 80 mph............   6.7 sec.
                       0- 90 mph............   7.6 sec.
                       0-100 mph............   8.7 sec.
 
                      Time to Distance:                
                       0- 100 ft............   2.6 sec.
                       0- 500 ft............   6.9 sec.
                       0-1320 ft.(1/4 mile).  12.3 sec.
                                          @  120.1 mph 
 
                      Top Speed............. 186.9 mph 

 

·
Registered
Joined
·
1,597 Posts
I think the point on what rpm peak power occurs is a big part of the top speed calc.
Standard Aero at 5k rpm is probably at about 200bhp (= 150mph)
I reckon with most tuned cars getting peak power at around 5.5k rpm then 165mph is definitely possible.
With 420bhp I'd guess you'll run out of gears and hit the limiter at 6k+ unless power falls off very fast after 5.5k. What rpm is the 420bhp at?

Also - I note that the 9k has a cd of 0.32 - The new audi A4/A6 are down to about 0.28 which at 150+ must make a massive difference in the power required for top speed.

Once I get my stage4, I'll report back from the Autobahn...
 

·
Registered
Joined
·
4,215 Posts
Discussion Starter · #19 ·
no dyno runs yet...
but the last one was making max power at 6500 an max torque at 4000
1500 36.2
2000 57.8
2500 84.6
3000 126.6
3500 240.2
4000 301.2
4500 313.0
5000 356.5
5500 370.2
6000 391.0
6500 403.3

the engine's character is very different from this now
it comes in earlier and is more linear
 
1 - 20 of 32 Posts
Top