well the title says it all i just bought a 84 trans am t top 305 the guy i bough the car from said that the motor trany and rearend was compleatly rebuilt and only has 41 mile on them but the motor make a slight knocking sound not sure where its coming from if anyone would have any idea please let me know ive changed the oil plugs plug wires new radiator thing i thouh it could be besides the new radiator wheni boug the car the radiator was blown in it

 

could it be spark knock? what type of fuel are you running? does it knock all the time?

 

im running super unleaded in it right now im not driving the car rightnow since i have no exhaust on it and haft to replace the manafold do to i have headman headers on it witch i was told would pass inspection with them on it i also have acdelco r45ts for my sprak plugs

 

shorties or longtubes?

 

hmm im not sure it could be a rod bearing if the car was overheated when it lost the radiator hard saying you must be running the headers without the smog holes is this a carbed car?

 

I dont think so. If he would of spun a bearing there would have been metal shavings in the oil when he changed it. If he has hedman lontubes one of the tubes might be hittings something causing the knocking.

 

at first i was thinking spark knock. yeah thats a point but he said that he is unable to detect where its coming from though i would think you be able to get a pretty good idea if it were that but he is dumping straight out the headers. lol

 

theses are headman shorties im running

 

here is a pic of the motor im rebuilding agean since it seams the guy i bought th car from dosnt know how to do things right think god i have 3 other mechanic's in my family

 

look at the drivers side from top an see if your headers are coming in contact with anything both sides while your at it.

 

[/IMG]here is a pic of the motor im rebuilding agean since it seams the guy i bought th car from dosnt know

 

yeah if you are doin that id loose the lime green paint

 

Do you have any pipes bolted to the shorties or they running open?

 

there running open

 

also i am deffently loosing the lime green paint going eachter fire red or gm orange

 

You can fry valves like that because of the lack of backpressure. Is the motor shaking alot like it is missing? If it is then it sounds like you warped a valve.

 

no the motor dosnt shake but i know my uncle said it was a little out of time not much just a little would that cause the slight knock in it

 

yes its called spark knock how much timing do you have dialed into it total timing im guessing on that should be between 28to 34 degrees or just loosein distrib slightly just enough to turn an retard till goes away

 

my uncle turned the dest last night when he noticed the knock and it didnt change anything

also here is a little about what is in the motor its a 305 with 350 heads forge pistons 650 cfm card from eb and eb intake hydro cam with the headman shorty headers. as far as i know thats what all has been put into the motor

 

well found out what the knocking was i have a rod knocking witch sucks cause this motor was saposavy rebuild 41 miles ago so now i haft to rebuild it agean anyone know how much a sb chevy rebuild kit runs

 

well you said 305 with 350 heads correct? well if this is the case id get a new 350 call around to your local junk yards pic up something for under a 1000 ready to set in id re ring it an invest in a gasket set you have a intake an carb so just match a cam to it an if you want to go out there alittle bit do some head work. good luck. i do have a 305 in my garage with 60 thousand original miles if interested.

 

Dont spend 1000 on a junkyard motor. You can get a rebuilt one with a waranty for alittle over that.

 

he is right it just depends what you want. i garantee the motor he spends a grand on will no way compete with my freshened junkyard motor an if you have family with knowledge willing to help listen to them either way you go you will have a good runner.

 

thanks guys for all your info on this right now the more and more i think about this the more it ****'s me off the fact is i bought this car for $2000 and the motor trany and rearend was all rebuilt now im finding out the more i dig into this car the more i finde out he ****ed alot of **** up and i haft to have it rebuilt agean also my trany isnt working correctly my uncle tryed to put it up on car ramps and it wouldnt make it up them just about half way before it stalled out looks like im rebuilding a rebuild motor and trany whats next the rear end " knock on wood" if any of ya have yahoo pop me a message my name is missouri_guy64504

 

do your homework keep your options open and you will learn alot and have a good fun runner good luck

 

Some of them motors run prety good. My friend got one with flattops and a towing cam, paid 1200 for it (Stock rebuild was 900 i think) and he is in the 13s. Only thing that is done to the car is headers, old intake, and an edlebrock 600 cfm carb.

 

ok when it come to working on cars i am deffently a noob i just remambered when i replaced the radiator i had to unhook the trany cooler witched drained all the trans coolent out of it and when i hooked everything back up i didnt add new transmition collent duh scott how retared are you im just hopping thats was the problem and the trans isny messed up

 

Dont wory about it. Everyone makes mistakes, all you can do is hope you dont make any big ones that messes up everything. I doubt that you hurt the trany, just add enough fluid and c if everything is fine.

 

hey necro you have yahoo or aim

 

i was wondering since it a slight knock and it only gets worse when you rev the motor would that be a rod or a loose lifter

 

I dont think you can have a lose lifter, a rod knock or a loose rocker would probably be the best bet, wish you luck on this!

 

how is the oil pressure?

 

i read ablout 20 psi on my aftermarket gauge

 

well guys how things going i still have that slight knock at time not sure whats going on there sometimes you can hear it sometimes you cant my trany still isnt working. anyways i bought a 350 block its sitting at the shop getting ready to be built after christmas also bought a th350 for 100 bucks and im thinking of buying a ford 9" 4.10 ratio rearend but not sure if i want to put that in or not do to i know no idea what im doing still but learing as time gose by.

 

well after mounths of work on my car i have replace the trany with a th350 but still have the knock but am able to tell where its comming from sounds like its coming from the fround of the motor around the water pump. if this gives you any help

 

Why'd you go to a non od trans? Since it's coming from inside your block it's definitely time to be thinking about an engine to replace it when it goes boom. Aside from rebuiling your 305(terrible idea) nothing will fix that knock.