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Ed,
The happy place with your motor even with your cams is under 7500RPM. Pityful admittedly, but to get HP numbers that you don`t have to mumble about under your breath you have to over rev the motor. Look where they are. Sorry.
I think you will find that your cam profiles are about those below adjusted for years of wear.
Cam Lift & Duration
Lift Max: .410 Duration (in degrees)
.001 360
.010 320
.020 290
.040 270
.050 260
.080 246
.100 234
.150 214
.200 188
.250 160
.300 132
.350 96
.400 34.410 Max lift
These are real typical of old design Alfa race cams copied by builders even today with just more lift and duration.
If I wanted replace the pityful I would address the ramp numbers that I highlighted in red to reduce overlap (and to increase length of the power stroke).
The durations in green represent the lifts over 50% of cam lift which is where mixture flow is obviously going to be best. This is a small port small valve motor, these numbers need to be improved.
If you are running the same cams intake and exhaust you are twice escrewed.
Compare the duration of the old Autodelta cams with the cams below that are in some GTA`s in Europe that are being driven to the track and winning!
These are not all out race cams. Thay make tons of torque in the small motors between 5000 -7000 RPM and pull from 3500 RPM resonably Look how close the duration numbers on the intake cam is fron .040 to .200. But the addtional .025 lift allows an tremendous increase in breathing from the point of real flow at .200 until the valve returns to slowing the flow. As well the assymetric application improves the combustion timing events to get the best torque production. Forget HP. Torque makes the car drivable. Torque wins races. These designs keeps your motor producing where it can live a long happy life. You can leave your wallet on it at night and know it will be there in the ayem!
Intake Exhaust
Lift .435 .435
.010 292 287
.020. 288 272
.040 267 260
.050 261 256
.100 234 228
.150 218 212
.200 189 182
.300 140 134
.400 72 68
.425 16 10
Max .435 Max .435
__________________
Richard Jemison
RJR Racing
http://scuderiagiallo.com
"you don`t have to listen, but you won`t win the argument"!
"Nothing that I might suggest will be legal in California"
Last edited by Alfar7; 05-09-2008 at 07:54 AM.
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