Hey, im about to get angry, if im going to have a problem here. Ok, the deal is, I am doing an engine swap in my 83 TA. I pulled out my 305, and i have a '78 350 block. I do not know the casting # on the heads. I bought the engine off of a guy at work, and its all cool, except for when i tried to put my exaust manifolds on. Yeah, can any one call what happend? 3 out of 4 bolt holes lined up, the one in the very back did not. Also this engine is a drivers side dipstick, and my manifold does not clear it. So, i drove all the way out to summit today. (luckily for me its about 1hour) picked up some summit headers (ya i know they are flowtech too) and a flowtech Y pipe, (hey, atleast its a bolt on Y pipe). But it got dark before i had a chance to try to bolt the headers on the block. My question is, if these headers are made for 82-92 F bodys, Am i still going to have this same problem? The guys at summit did not hear of such a thing, but i swear it did not line up. Also the dipstick was totaly in the way of the manifold, but i dont know about with the headers. I know i got to test fit them, but i canot do it untill thursday.

So, does anyone know whats going on? Im thinking i have non smog heads on my new engine, and maybe the one bolt hole is diffrent between the smog and no smog heads. But if they are, and my headers are made for smog heads, how the heck do i get an exaust on this car? Its frustrating to think about.

Anyway, If you can help me out, thats one less step im going to take twards the cliff, pushing my car off.

BTW, i also posted this in the exaust forum, but i need all the help i can get. Thanks.

 

Ive had the same headers bolted up to stock 76 casting, stock 82 casting and now Vortecs. All the same. I really could not see your headers not lining up. They should work fine.

 

ya, my stock manifolds matched the exaust ports on the heads, but one bolt was off. it straight up did not align. it was off by atleast 1/2 inch (just guessin here, but no way in hell it was off a little)

I do not know anything about these heads, other than they are chevy, and not the stock ones off of that block.

Also my dipstick is on the other side of the engine. (now drivers side, used to be passanger) Will the summit headers fix the clearance problem, because i know the stock manifold did not fit, because of where the manifold turned down to the Y pipe is where the dipstick handle is.

THANKS.

 

They started using a "7th bolt hole" sometime in the late 70's-early 80's. Both heads have it, but only the passenger side uses it (back most bolt in place of the bolt right next to the exhaust port). I don't recall the reason for it (does the factory need a reason to do silly things?).

Since earlier heads didn't have it, that later manifold won't bolt to earlier heads with all 6 bolts. However, headers always use the old 6-bolt pattern, so all headers will bolt to all (regular) SBC heads.

 

as far as I can tell, they did it to still have a decent amount of flow when the outlet goes down at an angle way in the back on the pass side , this became common in the late late 70's and early 80's, since thje engine compartments became more compact

 

That could be it. In order to get the outlet on the back, thinking about the way stock manifolds look.

 

hey, thanks guys. I was seriously worried. my first time doing this, and i just kept hitting brick walls. wasnt fun. First, the manifolds, then speedomoter (took out cruise controll, and the stock cable wont fit now) then i realize my frame where the transmission cross member bolts up to is rotted out on one side, AFTER i pay the car off, and put the engine in, then the other transmission bolt holes were stripped out, and well, it sucked.

But the headers will bolt up, but havent got the chance yet, i just welded in new metal to the frame, and got the transmission bolted up last nite, and i was done for the day.

Thanks again.

 

i had a similar thing happen with a set of exhaust manifolds apparently mine were bent oir something because i took them off then tried to put em back on and they didnt fit ended up having to heat them up and spread them till i got the last bolt in the hole

 

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