I have just bought a 1994 camaro z28 It had a manifold leak I took apart the manifold and found that two of the bolts had been broken off what is the easiest way to fix this problem

 

the bolts need to be tap and drilled out

 

Are they broken off flush with the head? I guess they probably are, since that's usually how most bolts snap off! It depends on what made them snap. Were they over-torqued and broken off while tightening? Then they could be a beech to get out. If they just snapped from fatigue, they might not be frozen to the head. Soak them with penetrating oil, heat the crap out of them with a blow torch, and try to tap the broken bolt out with a sharp center punch and hammer. Sink the punch into the bolt off-center trying to wind it out counter-clockwise as you smack it with the hammer. You might get lucky and get it out that way, which is easier than drill & tap.

 

Try above first
If you do have to Drill and Tap try a left hand drill bit. I found that the heat and vibration of the drill will walk out the broke bolt most of the time. As long as you use the right size you can always tap it if it does not come out with the drill.

 

just be careful where you bring it if you dont get it out yourself. i couldnt get mine out so i had mine done at a trusted mechanic who had done numerous ones before. they drilled to far in and hit my water jacket. long story short they had to take apart almost my whole block, put new gaskets, readjusted my rocker arms, retimed my engine, cleaned off my intake manifold, new bolts, and sent the rest in to a specialty shop to close the water jacket back up and rethread it. total price $90 for labor