Has anyone successfully drilled and tapped an exhaust manifold bolt broke flush to the head, with the head bolted on the block still in the car? And of course its driver side closest to the firewall. Just wanted to see if it could be done, being as I really don't want to pull the head. I have a sneaking suspicion that its going to come down to that.... thanks.

 

This is VERY difficult! Whatever you do, don't use an ez out! It'll crack and you'll be totally screwed.
Try to heat cycle it, torch/spray with upside down can of compressed air, etc. It'll break it loose. Try PB blaster as well.
You might be able to drill with a left hand drill, if that doesn't work, use a LH tap as well, and put in a LH bolt until it stops. Then try to break it loose by tightening the bolt. 5/16" should work.

 

believe it or not, somtimes you can get away with spinning them off with a pic or punch and hammer since after they snap off they dont have that tension and they come right out. If your lucky. if not, it will be rusty and stuck like hell.

Is your manifold off? you will at minimum have to take that off and go from there. Head. you shouldnt have to take off. At most, just take the inner fender out and you can get at it pretty easy.

 

The manifold is off and luckily that is the only one that snapped. I'll try the punch when I get home from work in the morning but from the look of the other bolts I'm pretty sure its seized up good. Hopefully with the inner fender out I can get enough access to fit a drill, and keep it straight.

 

well upon further inspection I feel that I have to remove the head to properly drill and tap the bolt. which makes me believe i opened a can of worms, good time for a new intake?

 

stock car? you can do up an edelbrock 7104, q-jet performer RPM. I wouldn't spend the cash at this point though... I would replace the valve springs and seals though...

 

yeah its totally stock... which now im at a crossroads, should I put more money in this thing or just go 350.... I removed air pump because it was seized replaced all vacuum lines, thats it. lol i just wanted some headers