New engine running...Got some problems/Questions?

[latham83]

Hey just got my car running again...brand new 306 with all the mods...check out my sig...well it runs freakin awesome...my question tho is ..i had it out twice already..alot of stop and go kinda stuff...and when i was pulling into a parking lot a very loud noise started coming from the engine...it was pretty damn loud cause it echoed off the walls of buildings and stuff...It really did not sound like an internal engine part..more or less of exhaust fluttering very loudly..
almost sounded like it was fluttering in my gt-40 intake.....so i shut it off..started it back up..sound was still there , then 10 secs later it went away..and didnt come back the rest of the night??? does anyone have any idea what that could be? i know at idle the intake whistles like a bitch...but this was alot different...

also.most of the time when i start her up...it revs up and down 3 or 4 times until it stays at steady idle...any idea how i can fix that?
my timing is at about 16 and fuel pressure at 47 without vacuum....
help me out if ya can guys..thanks...

 

[latham83]

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[HO93LX302]

Well i don't know about the noise, but as for the reving 3 or 4 times try cleaning your IAC solenoid.. It can be all carboned up

 

[QBstang87]

that seems like a whole lot of fuel pressure too, i run about 39-40 vaccuum off, with a built 302, h/c/i all that.

 

[latham83]

clean it out with what...i know it comes apart in like 2 pieces too..do i clean both of them?
what would happen if i just leave that thing disconnected? would it run better

 

[HO93LX302]

You could leave it disconected but you would have to open the throttle plate more.. If you disconect the iac the engine will stall.. Its supposed to anyway.. If it doesn't then it can be clogged.. Just take the 2 10mm bolts off and spray carb cleaner on the valve inside.. Before you do just notice if theres a lot of carbon build up..