No idea about vacuum.Will idle vac always go up when advancing the cam?
Can it decrease but your DCR comes on sooner?
my answers are No, and Yes. Am I wrong? Please discuss.
Yes, I'd like to know the thoughts on this as well. Most conversations regarding advancing the ICL are about an increase in DCR. Not much is said regarding how moving the cam forward affects the exhaust. I would say yes as well, given that the exhaust valve is now opening sooner.will advancing the lobes give me more exhaust energy?
I would say yes? With an earlier EVO happening?
all at a lower rpm with sacrifice to upper rpm potential?
Yes, I'd like to know the thoughts on this as well. Most conversations regarding advancing the ICL are about an increase in DCR. Not much is said regarding how moving the cam forward affects the exhaust. I would say yes as well, given that the exhaust valve is now opening sooner.
This could benefit some turbo guys if that is the case right?
In my case, I am on a 114 and put the cam on a 105 ICL
114 LSA with a 105 ICL puts the ECL @ 123if my numbers are right, it makes the exhaust act like its on about a 109 LCA, but you still have 114* LCA between the lobes.
that sounds good for many many things.
and yes, I'm turbo, but I'm also NA until mid-load 3800rpms.
on a short stroke 306
Hindsight, it looks like you had some good early exhaust events happening and then you traded for some late, smaller exhaust events happening?If it's personal experience you want...
I have a street car with occasional track duty and S-480 turbo.
I was using an off the shelf street solid roller 249/255 with a 110 lobe installed on a 106 centerline. It sounded great, was strong and responsive while out of boost, and coming into boost was a beast! (remember street car)
The trend at that time with turbo cars was to go to a slightly shorter duration single pattern with a wide lobe seperation. N/A cams were frowned upon.
Searching for more power (as always) I had one made 237/237 on a 115 on the suggestion of a well respected individual and installed it on a 111 ICL and the results out of boost (N/A) were dissapointing. It idled and performed like Grandma's station wagon.:-gay It was a turd until boost came in. Boost was much more controllable with the throttle application though and did not come on like a light switch.
I preferred the light switch hahaha!:smt081
In my personal experience, grinding a cam with a tighter lobe seperation like a 112 or a 110 would probably have been more agressive while out of boost and the ICL could still have been adjusted to move the DCR where needed to help spool. Hope my mistakes help you out!