how much vacuum is normal at idle on a motor like this

[Darufe]

looking for vacuum leeks but im also wondering

just how much vacuum is normal considering:

new not broken in motor
high lift high duration cams
oversized valves
heavily ported heads
no more VVT
CR lowered to 10:1
no more IAC, using drive by wire to adjust idle rpm
idle set to 1400 rpm when engine is cold (throtle plate open roughly 8%)

 

[2012 Boss 302]

10

 

[Darufe]

so im not too far off with my 7-8 cold
smoke machine comming in tomorrow to test for leeks
thanks!

 

[CPRsm]

Seems low. We lock out large cams and can still pull enough to operate the vacuum brakes

 

[slagburn]

I'd think at least 14_15?

 

[Darufe]

yeah im suspecting the meth bungs for atleast a few inches of vac.
im hoping its something simple and easy....
ive had so many issues/headaches building this thing im ready to lose it and buy a god damn minivan hahaha

 

[Blazer707@TBR]

I know normal vacuum on these cars at a hot idle is around 19-21 in hg.

 

[redline5.0]

yeah im suspecting the meth bungs for atleast a few inches of vac.
im hoping its something simple and easy....
ive had so many issues/headaches building this thing im ready to lose it and buy a god damn minivan hahaha

OP I know that feeling but there is light at the end of the tunnel lol. Don't stop now!

 

[Darufe]

Well put the smoker to it.
the throtle plate at rest on the acufab tb is pretty darn open.
found one small leak from an injector o-ring
and realised the port on the side where i had my bovs plumbed...isnt pierced through.

So option 1- take off the intake manifold strut tower brace
Fuel rails etc get a proper sized drill bit pierce it clean everything up.
2- t into one of the ports at the bavk of the IM

Option 2 sounds good to me lol

 

[Darufe]

well no other leaks from the somke test
still seing 70ish kpa at idle.
the new coils stabilised the idle quite a bit i can run 1100 rpm without it stalling but it still has its random burps.

dont know what else could be causing the lack of vacuum. could my ignition timing be that far off??
what else could it be?
or are the stage 3 mmr cams (wich i have no specs whatsoever for....) be that agressive that i cant get any more vac then that?!