B21a1 cams in my b20z/b18/b18b
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B21a1 cams in my b20z/b18/b18b
Well almost done with this project. Whats the point of doing it? Well after looking for crower cams and got to looking at stock cam specs found out that the b21a1 exhaust cam is .033 bigger than the stock b18b. Here are the specs. You see the b21a1 intake is smaller than the b18b so I am using b20z intake and b21a1 exhaust. Will have pics and updates of testing out in a week. The biggest task is machining a piece to extend the b21a1 cams since they are shorter. Some people told me its not worth it. I won't gain alot but will gain. Im also boosted so might help on that end.
b21a1 cams:
intake cam:
open point @ following lift at the valve:
0.010" 6 degrees BTDC
0.020" 8 degrees ATDC
0.030" 13 degrees ATDC
0.040" 17 degrees ATDC
0.050" 20 degrees ATDC
close point: @ following lift at the valve
0.010" 236 degrees ATDC
0.020" 220.5 degrees ATDC
0.030" 214 degrees ATDC
0.040" 210.5 degrees ATDC
0.050" 207.5 degrees ATDC
duration: @ following lift at the valve
0.010" 242 degrees
0.020" 212.5 degrees
0.030" 201 degrees
0.040" 193.5 degrees
0.050" 187.5 degrees
max lift:
0.3465" @ 115 degrees ATDC
0.204" lobe lift
lobe center:
114 degrees ATDC
valve lift at TDC:
0.013"
exhaust cam:
open point: @ following lift at the valve
0.010" 242.5 degrees BTDC
0.020" 226.5 degrees BTDC
0.030" 220 degrees BTDC
0.040" 216.5 degrees BTDC
0.050" 213.5 degrees BTDC
close point: @ following lift at the valve
0.010" 34 degrees ATDC
0.020" 4 degrees ATDC
0.030" 3.5 degrees BTDC
0.040" 8 degrees BTDC
0.050" 11.5 degrees BTDC
duration: @ following lift at the valve
0.010" 276.5 degrees
0.020" 230.5 degrees
0.030" 216.5 degrees
0.040" 208.5 degres
0.050" 202 degrees
max lift:
0.3815" @110 degrees BTDC
0.224" lobe lift
lobe center:
112.5 degrees BTDC
valve lift at TDC:
0.024"
valve overlap: (@ following lift at the valve)
0.010" 40 degrees
0.020" 4 degrees
0.030" NEGATIVE 16.5 degrees
0.040" NEGATIVE 25 degrees
0.050" NEGATIVE 31.5 degrees
b18b1 cams:
intake cam:
open point: (@ the following lift at the valve)
0.010" 2 degrees BTDC
0.020" 10 degrees ATDC
0.030" 14.5 degrees ATDC
0.040" 18 degrees ATDC
0.050" 20 degrees ATDC
close point: (@ following lift at the valve)
0.010" 242 degrees ATDC
0.020" 225 degrees ATDC
0.030" 220 degrees ATDC
0.040" 216 degrees ATDC
0.050" 213.5 degrees ATDC
duration (@ following lift at the valve)
0.010" 244 degrees
0.020" 215 degrees
0.030" 205.5 degrees
0.040" 198 degrees
0.050" 193.5 degrees
max lift:
0.388" @ 118 degrees ATDC
0.228" lobe lift
lobe center:
117 degrees ATDC
valve lift @TDC:
0.012"
exhaust cam:
open point: (@ following lift at the valve)
0.010" 259 degrees BTDC
0.020" 225 degrees BTDC
0.030" 219 degrees BTDC
0.040" 215 degrees BTDC
0.050" 212 degrees BTDC
close point: (@ following lift at the valve)
0.010" 15 degrees ATDC
0.020" 6 degrees BTDC
0.030" 12 degrees BTDC
0.040" 15 degrees BTDC
0.050" 18.5 degrees BTDC
duration (@ following lift at the valve)
0.010" 274 degrees
0.020" 219 degrees
0.030" 207 degrees
0.040" 200 degrees
0.050" 193.5 degrees
max lift:
0.3485" @115 degrees BTDC
0.205" lobe lift
lobe center:
115 degrees BTDC
valve lift @TDC:
0.017"
b21a1 cams:
intake cam:
open point @ following lift at the valve:
0.010" 6 degrees BTDC
0.020" 8 degrees ATDC
0.030" 13 degrees ATDC
0.040" 17 degrees ATDC
0.050" 20 degrees ATDC
close point: @ following lift at the valve
0.010" 236 degrees ATDC
0.020" 220.5 degrees ATDC
0.030" 214 degrees ATDC
0.040" 210.5 degrees ATDC
0.050" 207.5 degrees ATDC
duration: @ following lift at the valve
0.010" 242 degrees
0.020" 212.5 degrees
0.030" 201 degrees
0.040" 193.5 degrees
0.050" 187.5 degrees
max lift:
0.3465" @ 115 degrees ATDC
0.204" lobe lift
lobe center:
114 degrees ATDC
valve lift at TDC:
0.013"
exhaust cam:
open point: @ following lift at the valve
0.010" 242.5 degrees BTDC
0.020" 226.5 degrees BTDC
0.030" 220 degrees BTDC
0.040" 216.5 degrees BTDC
0.050" 213.5 degrees BTDC
close point: @ following lift at the valve
0.010" 34 degrees ATDC
0.020" 4 degrees ATDC
0.030" 3.5 degrees BTDC
0.040" 8 degrees BTDC
0.050" 11.5 degrees BTDC
duration: @ following lift at the valve
0.010" 276.5 degrees
0.020" 230.5 degrees
0.030" 216.5 degrees
0.040" 208.5 degres
0.050" 202 degrees
max lift:
0.3815" @110 degrees BTDC
0.224" lobe lift
lobe center:
112.5 degrees BTDC
valve lift at TDC:
0.024"
valve overlap: (@ following lift at the valve)
0.010" 40 degrees
0.020" 4 degrees
0.030" NEGATIVE 16.5 degrees
0.040" NEGATIVE 25 degrees
0.050" NEGATIVE 31.5 degrees
b18b1 cams:
intake cam:
open point: (@ the following lift at the valve)
0.010" 2 degrees BTDC
0.020" 10 degrees ATDC
0.030" 14.5 degrees ATDC
0.040" 18 degrees ATDC
0.050" 20 degrees ATDC
close point: (@ following lift at the valve)
0.010" 242 degrees ATDC
0.020" 225 degrees ATDC
0.030" 220 degrees ATDC
0.040" 216 degrees ATDC
0.050" 213.5 degrees ATDC
duration (@ following lift at the valve)
0.010" 244 degrees
0.020" 215 degrees
0.030" 205.5 degrees
0.040" 198 degrees
0.050" 193.5 degrees
max lift:
0.388" @ 118 degrees ATDC
0.228" lobe lift
lobe center:
117 degrees ATDC
valve lift @TDC:
0.012"
exhaust cam:
open point: (@ following lift at the valve)
0.010" 259 degrees BTDC
0.020" 225 degrees BTDC
0.030" 219 degrees BTDC
0.040" 215 degrees BTDC
0.050" 212 degrees BTDC
close point: (@ following lift at the valve)
0.010" 15 degrees ATDC
0.020" 6 degrees BTDC
0.030" 12 degrees BTDC
0.040" 15 degrees BTDC
0.050" 18.5 degrees BTDC
duration (@ following lift at the valve)
0.010" 274 degrees
0.020" 219 degrees
0.030" 207 degrees
0.040" 200 degrees
0.050" 193.5 degrees
max lift:
0.3485" @115 degrees BTDC
0.205" lobe lift
lobe center:
115 degrees BTDC
valve lift @TDC:
0.017"
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