A few guys have sent me dynos of the Downing/Atlanta with various other mods. The following is a quote posted on the message board May 10, 1999:
OK guys....here are the latest results from a dyno run on my '97 1.9 with the following:
"Fogged" Intake Plumbing
Downing/Atlanta Supercharger
Supersprint exhaust
Last time, peak hp was 155.7, peak torque was
140.1 ft/lbs. This translates to 192.2 hp at the flywheel. to 204.9
<24%>>
This time, I opened up the intake before the air-filter as per Shawn Fogg's article in MZ3 Net. Power and torque are up across the board , however the cut-off on these runs was made prematurely vs. last-time, perhaps costing me 2 or 3 horsepower at peak.
The results, 169.1 hp and 151.5 ft/lbs < a gain of 11.4>. Again, at 19%, these represent 208.8 hp at the flywheel .
These results, it should be noted, fell exactly on a line with the results on a '96 318ti with the Downing unit and a K&N cone filter....he topped out at 174 hp at 6300+ rpm......so I feel sure I am a little low on my max power here.....the figures are as follows:
RPM....HP..Torque
2200- 50 - N/A
2300- 53 - N/A
2400- 56 - 120
2500- 60 - 127
2600- 65 - 131
2700- 68 - 132
2800- 71 - 133
2900- 75 - 134
3000- 78 - 136
3100- 81 - 138
3200- 84 - 140
3300- 87 - 141
3400- 90 - 141
3500- 93 - 142
3600- 98 - 143
3700- 102 - 143
3800- 105 - 144
3900- 107 - 144
4000- 109 - 143
4100- 111 - 143
4200- 115 - 142
4300- 118 - 144
4400- 120 - 145
4500- 124 - 146
4600- 129 - 148
4700- 125 - 144
4800- 132 - 147
4900- 136 - 148
5000- 140 - 149
5100- 145 - 150
5200- 150 - 150
5300- 153 - 150
5400- 154 - 151
5500- 155 - 150
5600- 154 - 148
5700- 156 - 148
5800- 159 - 148
5900- 162 - 147
6000- 164 - 144
6100- 167 - 142
6200- 169 - N/A
The moral......the replacement of your stock airbox on a 1.9 with either a homemade or aftermarket cold air system seems to be a worthwhile investment.
Stewart
'97 1.9K
P.S. Be wery, wery, quiet...I'm hunting 2.8's!
An interesting note is that on the last run (the green trace) he removed the paper air filter from his airbox to see how much of a restriction, if any, it was. His power was very similiar to the other two runs so it is obvious the paper air filter was not holding his engine back.
This is my car on the dyno.
This is with the D/A, Fogged airbox, check valve, Remus exhaust, PCIII and NGK plugs and 94 octane fuel.