Thread: question about roller cam.

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someone told me that the dur@.050 on a hyd roller cam is like running a hyd cam with 10-15 more duration because of the fast ramp for the high lift. not sure i believe that.

i think this cam it too small for my engine.

lift
intake @cam 339 @ valve542
exhaust@cam 352 @valve563
rocker arm 1.6
cam timing@.004
intake- 32/74 ADV 286
exhaust-80/34 ADV294
cam timing@.050
intake-- 5/39 max lift 107 dur 224
exhaust 53/1 max lift 117 dur232 power range 2600-6100

i like this cam
intake @cam352 @valve563
exhaust@cam365 @valve584
cam timing @ .004
intake 38/76 ADV 294
exhaust 82.42 ADV 302
cam timing @ .050
intake 11/41 max lift 105 dur 232
exhaust 55/5 max lift 115 dur 240 power range 2900-6400

motor is a 401 forged rods and crank, indy heads/ flow 290@.500 and 315@.700
indy intake 10.7 to 1 i'm thinking 3200-3500 stall for the small cam and a 4000 stall with the bigger cam. i think the motor will just be to mild with the small cam. this is a street car with 3.70 gears and short 25.5 tall nitto 555'r 275/50/15's, no power adders.

techinspector would know this.....

i guess i should add this. the guy thats building the motor for me really likes the smaller cam. he feels the bigger cam would be too much and not be fun to drive on the street. he gives me a hard time when i say i want the bigger cam and tells me it's too much.

i feel with the smaller cam, i wasted my cash on the heads and intake. for one the intake is too much for the cam and the heads are over kill.

good think i can reuse the roller rockers. because i have a feeling next year i'll be installing the bigger cam.

from what desktop dyno 2003 says, theres a 20 hp differance between the two cams. 501hp to 521hp at the crank
torque is 401 at 2000 rpms on the small one and 380 @2000RPM for the bigger one.

looks like i could go with a 3000 stall for the small one and 3500 for the bigger one.

the car is around 3300-3400 lbs.

i'm thinking of getting the 3500 stall now so i don't need to buy another one when i put the bigger cam in but then again that a lot of work for 20 hp

thjanks for the info, i was posting while you posted.

i guess i said the wrong. what i meant was, will a hyd roller make as much power as a hyd with 10-15 more dur@.050?

wow cool more good info

well the heads are aluminum so pump gas should be fine on both right? i got some nice custom pistons. squish is be .037

thanks for your time and the good info

ps. as i was posting the second post i noticed i had the wrong setting for the cam in the desktop dyno. hp went from 550hp to 501 with it set right

i just hope this program is close. but it's been fun to play with for the last year