need help with 383 stroked and bored to 496
 

i have a 69 dodge dart with a 383 block stroked and bored to a 496 and recently it started acting very strange it has a horrible ping and knock from the engine and the idle speed shoots up and it wont go away i have gotten it to go away for short periods of time after pushing it into high rpms for a period of time but the engine noise and raised idle always ends up coming back after about 12 hours while its making that noise there is also an extreme loss of power this all happened after recently changing my alternater does anyone have any idea what could cause this i was told by one shop i needed to run higher octane because of my 25-1 compression but im running 110 octane and the problem still persists i need help!!!

What was wrong with the old alternator?
Did you replace it with the same model?

not sure if the 110 octane is good enough for 25 to 1 compression
how did you get the compression to be that high?

25 to 1 ?!?!?!?!?! thats crazy. are you sure its that high?

Im sure who ever told you your engine was at 25-1 is that they lost there marbles along time ago, losing power sounds like cam bearing or rod bearing failure, try using E85 fuel in it once and see what happens if you really do have that kind of compression , i would really check your timing and advance it bout 3 degrees from where it is now and see where that takes you :)

yeah, that sounds way whack. maybe 12.5 to 1. thats pretty high in itself .id go w/ chally`s anser you can have a rod or main bearing thats slapping around to give you the knocking noise. how much oil pressure are you running when at idle, then at say 3000 rpm.s

depending on how its is built, I could understand up to 15:1 but even then thats pushing it.

X3 on the timing check. the chain could have stretched a little.

69 dart
 

i replaced the altenator because my starter positive post grounded to my block and blew the diodes on the altenater i also noticed to day while i was under the hood there was a small amount of smoke coming from the breather on the valve cover while idleing i need to get my car running soon and every time i take it to a shop and they fix something that causes something else to happen

any ideas whats going on