Cam selection in initial set up
How critical is the cam selection in the initial set up?
That depends on a lot of factors. What engine and what cam specs?
I'm just starting to tune my 600 - I have a 440 Mopar bored .040 over and 1.6 ratio rocker arms. Comp Cams -23-710-9 roller rockers. I was thinking a 3 for the cam setting.
Lobe Seperation 110 deg
Duration I: 274 E:282
Lift I: 538 E: 534
Centerline 106 deg
Quote from northstar on August 19, 2019, 11:55 amI'm just starting to tune my 600 - I have a 440 Mopar bored .040 over and 1.6 ratio rocker arms. Comp Cams -23-710-9 roller rockers. I was thinking a 3 for the cam setting.
Lobe Seperation 110 deg
Duration I: 274 E:282
Lift I: 538 E: 534
Centerline 106 deg
Cam 3 will be worth a try. May be cam 2.
I know nothing about my 283. It has a very slight lopy idle. It has about 11 vacuum at idle, and needs a little higher octane fuel than regular.
What's the pros and cons of choosing cam selection 1 vs 2 vs 3 vs 4?
What does choosing cam selection 1 vs 2 vs 3 vs 4 change?
I have about the same cam spec on a big block and I notice mine ran better on cam 2 on fitech website they give cam setting recommendations and I followed that seems to work good
I found this on the Fitech websot:
Choosing a cam selection:
Cam selection is based on vacuum load of the engine. Cam 1 is for 15Hg or above, Cam 2 is for 10Hg to 15hg, Cam 3 is 8Hg to 10Hg, Cam 4 is 8Hg to 6Hg. These are estimates and you may need to switch between them if the vacuum load is between two different cam settings to get the engine to run better for your application.
In terms of vacuum, where are we measuring from? I tried the vacuum port for the distributor at 0-8 and from the manifold it is 14-23. The low side is at idle and the high is at 4000 rpm.
manifold vacuum, and the different cam settings sets up different fuel trim and delivery table as a baseline for the fitech to adjust from at least its the way I understood it from fitech example if I had 14 inches hg I could select c1 but depending on what I have twin bodies or blown high compression or 9-1 I could also select cam 2 for a richer table for what I am running just half to see what works best for you application starting from your idle hg