Re: 1996 5.7LX Dryjoint exhaust upgrade?
The reason the manifolds are being changed is due to a crack that then allowed water to enter into the head. The shock of the cold shrunk a valve seat and it went bouncing inside the engine.
The story behind this engine is this happened once two years ago and the engine was rebuilt. It was not ran until this season when I purchased it. On the third outing with it this summer it happened again.
I pulled the engine and tore it down, when I saw that #6 dropped a seat I called the original owner who confirmed that was the same cylinder. A look inside the manifold told the story. The boat shop that did the work evedintly never inspected the exhaust so the engine was doomed from the word go.
The first time it happened a original OEM head (not rebuilt) was purchased and installed. Since it was trashed, I purchased Vortec heads, a cast vortec manifold and a 4bbl carb. Had the engine go through a machine shop, cylinders bored, crank polished, installed roller cam (Stock mercruiser specs, I belive it is the GM RAMJET cam) Roller lifters. I would hate to venture as to what I have into this thing but I am sure it is around 4000.00 but I have been having fun doing it - as my background is aviation maintenance.
Any ways I loved the hull this engine was is (96 celebrity 190) SO I am making what I think will be a primo ride, and I like to have nice equipment and think the cooling system would be neat. (Block was cleaned, new heads, new intake, will have new exhaust) so no worries about scale in the motor. Currently replacing the stringers and deck but thats a different story alltogether.
