355 twin turbo hard time getting motor to idle good

m having a really hard time tunning my idle on this motor and i dont think it should lope as bad as it does .

if i set the idle to 600 rpms it lopes from 6-1000 rpms, now i have the lowest part of the idle set to about 900/950 and it is loping to about 1100-1150

the combo is tpi intake 9.2-1 cr cam is 234° / 244°, .488" / .510" 109lsa
ive tried setting the timming anywere between 16* all the way upto 32* at ilde 32* gets me the smallest amount of lope but i dont think this cam should be loping as hard as it does

heres a lil video

http://videos.streetfire.net/video/blah2_2333530.htm
thats with the idle set up high and alot of timing

i know the cam isnt really good for my app but its what i had, eventually i will swap it out for a 224/224 .510/.510 on 112 lsa


but i dont think this cam should have that rough of an idle
any thoughts or suggestions guys ???


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could be any # of issues. firstly i would go over the tpi setup and make sure it dose not have any vacuum leaks this can be a pita and cause your problem. secondly i would get the turbos plumed in. i seen they were off in the video. is it a map or a maf car? have you had your chip tuned?

i need to get a 90* 3 inch coupler to get the pipes from the intercooler to the throttle body still.

its a speed density system im running an aftermarket megasquirt ecu that i am tunning myself, this will be my 3rd turbo camaro ive owned and tuned so thats not an issue.

i did check for vacum leaks and everything is sealed up well, when i got the car somone had removed the original tpi and installed a carb,the cam loped pretty hard with the carb on it as well.

im almost starting to think the cam is actually larger then what i was told

it pulls good vacum until the rpms drop then it pulls good vacum when they come up again.

i forget the conversion from the kpa to inches of vacum in the software but the map gauge reads from 25kpa to 44kpa during idle. im also at dam near 6kft above sealevel so with the engine off my map sensor reads 80-86 kpa depndign on the weather instead of 100 if i was at sealevel.

i just moved here so this is my first time trying to tune anything at this kind of altitude

disreguard the max rpm of 15K i had the log view software to display rpm x100 instead of x10

but here u can see what the fuel and map is doing

Divide kPa by 6.8 to get psi. From the video, it does not sound like cam lope, to regular and even, to me. Sounds more like idle surge, what are the counts on the IAC showing? Definately look for vacuum leaks, they can cause this surge, also make sure your MAP and tuning is set up for boost, as boost uses a different setpoint for low vacuum than non boosted.

it apears the manifold may be leaking from the back china wall, just for the hell of it today i got the motor fired up and warmed up and put my hand over the throttle body and the motor still continued to run. i cant hear a vacum leak but then again the downpipes exit right behind the front tires so its a lil hard to hear anything.

im going to yank the manifold reseal it and see what happens

be thorough cleaning it and apply a thin coat of RTV to EVERYTHING. I will never install a dry intake gasket ever again.

manifold is good did a fuel presure test and fp is bouncing between 15-27 psi looks like my brand new areomotive fuel pump went out

sending pumps back to areomotive for replacements.

how do u guys feel that cam should idle, im assuming it will be a lil rough at idle
while the car is down with the tank out im debating on swapping in the 224/224 cam

My Purple Shaft 509 108 lsp is viscous in a 440mopar

the separation at that degree is to create more vacuum to fill the cyclinders

at higher RPMs.110-114 is great for charged system as it shuts the valves

to allow more charged air into the cylinder.109 its going to be choppy.

Checking the injector timing on -off cycle.

http://www.google.com/imgres?q=lobe...1t:429,r:3,s:24

http://www.google.com/imgres?q=lobe...40&tx=159&ty=57

these diagrams are close to explaining lobe sep

i ended up pulling the cam out and putting the 224/224 in,car idles like stock now. im going to look into something a lil larger for when i ditch the tpi intake and swap on a vic jr efi. though at that point i will prolly get a set of afr 220's or just do a set of vortecs