L18 exhaust manifold

[maximo]

Ok, so I got rid of all the egr crap from my L20B, and I put an exhaust mani from a L18, but now the pipe coming from the exhaust mani is hitting the bell housing of my tranny, is a 5 speed. How did you guys fix that problem, another concern is that the pipe coming out of the exhaust mani is one inch diameter and the one on my truck is 2-1/4, how did you guys deal with that.

[datzenmike]

There's no gain to switching to the L16/18 manifold. It's only for looks to get rid of the EGR and air pump tubes. Also the L18 manifold should have two pipes coming out of it and joining into one larger 1 7/8"? pipe. I would buy the down pipe for the L18 manifold for the '74 truck. It should clear the tranny, then join it to the larger pipe to the muffler with a reducer and a couple of clamps.

[motavated]

There's no gain to switching to the L16/18 manifold. It's only for looks to get rid of the EGR and air pump tubes. Also the L18 manifold should have two pipes coming out of it and joining into one larger 1 7/8"? pipe. I would buy the down pipe for the L18 manifold for the '74 truck. It should clear the tranny, then join it to the larger pipe to the muffler with a reducer and a couple of clamps.

 

Mike that pipe is too small. Will more Hp be gained if cut and welded in a 2 inch from the flange to the back?