Any white smoke out the tail pipes when it happened?

Sounds like you are sucking air.. most likely lower intake..

white smoke bellowign out of the tailpipes would be a head gasket; but, if you dont see any anti-freeze contaminated oil the maybe that's not your issue.

I would suspect the lower intake, the huge vaccum leak that could be causing your idel and spiked rpm issues; I would pull off the upper intake, inspect it and see what you find on the lower.

I wonder....if the pop was an backfire in the intake itself.  therefore the backfire caused the intake to crack maybe?   and if so...maybe you'll luck out and not have any actual engine damage.

even if you find a cracked intake and replace it....i would find out what is causing your backfire....check timing, maybe get a tune.  If it would me i'd research all possible causes for a backfire.  I know some smog stuff can cause Afterfire, but that's when it happens in the exhaust not the intake.

for the record:  i had a decent sized air leak in my lower intake and it caused my car to run at 2krpm very often and spike up to 2.5k rpm also.  I imagine a huge lower intake leak from some crack could get you to the 4k you saw.

Thanks J and Nicole, you both alwasy help me out, i didnt notice any white smoke, but then again it was night, and i couldnt really see, and i was focusing on getting it down the street to get home, i thought lower intake because i dont see coolant in my oil, it explains my vacuum loss, maybe the intake had a hairline fracture and boosting it was enough to make it go the rest of the way. Thanks both of you

make sure you post back what you find!

It was the lower intake, hairline crack that killed the gaskets, so i went with a Trickflow street intake, but 2 weeks later it happened again, so i think there is something else wrong, so this weekend tear down starts again, and gotta figure this out, need it ready for cruise season, but this time there is some spray coming from my exhaust, minimal, so i think the intake is the issure with my idle being screwed up again, but i have to check to see it my head gaskets went bad, i dont know why they would, but its just my luck

if you say you had this happen twice now?  yea, i would try to find out why the backfire even is happening...

are you still running the egr?  something not right with teh air/fuel...but why... is the question that you need answered.

if it were me i would install a air/ful ratio gauge AND take it for a dyno tune, especially if your running a supercharger; not sure if you already are running a custom chip yet or not; but a dyno can help figure out quite a bit, including getting a good tune on the car. 

keep us posted....

yeah, i read up on your mods again...i hope you got a dyno tune after that build.

what's your timing at?

I dont remmber where timing is set, but we did retard it, I will have to look that up, and again, it was the gaskets blown out, no problem with the intake though, i have a ticking now, sounds like when my rocker arm was loose, so today I am taking valve covers off and double checking all of those, if thats not the problem, and nothing obvious jumps out, i may have to start disassembly again until i figure this out.

as far as a tune i have the AFM PMS4 so everything is in a good range, only thing is i still run too rich, need to read up more on programming fuel tables and spark advance at different RPM ranges when boosted.

So took valve covers off, and every rocker arm was tight, not a single problem, put it back together, and it wont even start now, im taking the day off, enjoying my one day off work, next weekend it starts again, I jsut dont understand how it worked fine, except for the lower intake gasket,  fix that, put it right back together and nothing but problems now, next weekend we get answers.

Damn that sux bro. I'm all ears for the results cuz I have plans in the works for 8 litres of WTF in the S-197. A very sincere good luck. I'm rooting for you!

So nothing was loose, and the ticking stopped, still havent figured that one out. My plugs were fouled couldnt even get spark, replaced those now it starts, doesnt run well, and i cant put it in gear without it stalling. this has turned into a way bigger job then it should have been.

Rub, sounds like that should be pretty damn awesme.

at this point i would wonder if the issue is comp control induced?

I just mesed around, checked all the connections, and I think i may have has a plug wire that wasnt on well, but i have the AFM PMS4 and on the display screen at idle my O2 sensors arent reading anything, but if i give it gas i get a reading, i wonder that since my plugs were fouled that prehaps my O2 sensors are all fouled out as well, once it stops raining i may check those, hopfully its something stupid and simple, id rather feel stupid, and have my car back then be where i am now.

true story

Exactly, I may be burning oil, so head gasket? piston ring? if it is, im going forged rotating assembly and dish pistons and bigger cam still. oh well, need to get some help over here to help me think through this.

had a friend who had a similar issue.... but his was due to a slipped timing chain.... this one sounds like something electrical/timing related ...... but ...the initial beginning of this was lost vaccuum after a popping sound... gotta be something simple that ties the two together.

check on the 02 sensors; remember the reading the comp gets from them will advance or retard the timing.  

What confuses me is the fact at idle the O2 sensors dont read, but if i give it any gas, they read, i had a similar issue when i had a bad vacuum leak, and i cant find a single one, im thinking about hunting down a smoke machine again to see what happens, and check the O2 sensors again, but the smoke out of the exhaust makes me wonder if i am burning oil.

I did have an intake leak, a fuel injector o ring was torn, replaced them all, and no leak, but now.... i think my IAC is going bad, new one will be in shortly.

you got lots of bad luck dont you?

I am Muyphys law... 

So i got my new IAC in, and that did nothing, i finally got it to run, and now it idles very rough, and it holds 2000-2200 RPM and wont drop down... im really hoping i dont have another intake leak somewhere. It seems to be doing liek you had said before when you had the cracked intake,