I have a 5k rebuilt with 20 over piston and cam grind of 262 in my kp36 pick up daily driver. Those are the only modifications to the engine. the exhaust is two inches from manifold back. Thinking of getting a 32/36 Weber, the question; with this set up is it necessary to put on extractors? I currently have stock intake and exhaust manifold and carby off a 3k. I know that generally cam, carby and extractors go together. I live in Central America and getting extractors is not very easy. Any input.... Thanks

Extractors are recommended but not necessary.

Extractors are often fairly fragile also. You may wish to consider finding a spare standard exhaust manifold and getting that cleaned up internally (as well as your inlet manifold).

 

Also match port both the inlet and exhaust manifold to your head.

Theres two types of standard exhaust manifolds, 4 - 1 and 4 - 2. Recomend 4-2 style,

 

Matching exhaustports may not be a good idea. Having larger ports in manifold than head

 

apperantly helps avoiding exhaust gas revertion

Thanks for your input, it´s appreciated...

Edited April 23, 201511 yr by Kflett