Strange ticking noise...

[sircruisealotVS]

alrighty, so ive got this strange ticking noise - im just after a few ideas on where to start looking as its quite unusual.

for starters, just as some supporting info, my VS is a blown and stroked V6, has been for a while now and normally runs beatifully all the time as my daily.
now about 2 months ago, i noticed after giving it a decent serve of throttle (this was on a dyno mind you, not the street) that afterwards it was ticking a little bit...
didnt think too much of it at first as it was fairly quiet and went away when the engine was left to idle.

now as the QLD summer is starting to really kick in, on the hot ass days if im driving for a while (like over 30mins) it starts to do this ticking noise, quite loudly and in time to rpm (gets more consistent with more throttle) but goes away if you plant it. its mainly noticable from idle to 3000rpm and the exhaust note becomes somewhat "tractorish" at low rpm when taking off from a standstill.

so its definately not a consistant thing, it doesnt do it all the time - its usually only on my days off when i drive more that it does it as my normal drive to work is only 10mins. it seems to be heat agitated and can come and go multiple times during driving, usually settling down when at idle.
so...wtf do people think is going on? ive got my ideas, but im just seeing if other's have some ideas of their own to help me track down the problem.

[StockoVRWagz]

sometimes my car also does this. It ends up that one or two boldts on the exhaust manifold are loose and I tighten them and it goes away

[hako]

If not the exhaust manifold as xcopv-8 suggests, it may be a lifter leaking down...maybe has dirt or is worn or whatever. Also maybe a thicker oil will quieten it down although that doesn't fix the problem.

[immortality]

a oil pressure gauge would be real handy at this point. do you still have the ballance shaft fitted?

[ScoHar]

check exhaust, does your oil pressure light take longer than usual to go away? could be an oil related/lifters problem. but my bet is its exhaust.

[bittsa]

my engine did this for 4 days, then pttf! nothing. seized on the highway! i still dont know why, but it would just start tickin at random. i would pull over, put a little oil in and it would shut up. ten i didnt pull over and yeah.... $600 later i have another engine

[sircruisealotVS]

cheers guys, that pretty much backs up my thoughts of it most likely being the extractors.
i did think about it being rocker assembly/lifter related, but i know what that sounds like and it doesnt sound the same way as what im getting. definately leaning towards an exhaust leak. once the engine is cool ill go have a better look at the manifold bolts and start from there.

[sircruisealotVS]

just a follow up, incase anyone reading through posts wanted to know the problem. it turned out to be a shot exhaust flange gasket, just before one of my cats and one of the flange bolts was almost undone too.
so not quite was i was originally thinking, but damn close. all fixed now with two new gaskets and bolts.

[pursuit_special]

Good on you for the follow up sircruisealotVS, not many people do it these days on tech forums. Thumbs up.