Two month ago I posted success on finishing up my engine bay. Well, that was two month ago. One Sunday morning while happily terminating my dash electrical system and probably drinking too much coffee something hit me. Going back to the beginnings on my build log I was dreaming of using an LS7 with ITBs until the LS7 based Mercury motor became an opportunity with its stock dual throttle body configuration and the ITB idea died. Now over a year later after buying the motor and knowing much more about the engines build quality and its theoretical performance it was time to take the shackles off. I am about to find out what is behind those high airflow values of these cylinder heads. The proprietary wiring and locked ECU was removed including the restrictive intake and the calculations started on a design of a complete new induction system without bottle necks and restraints. The best naturally aspirated design so far is a custom ITB system for these cylinder heads based on tapered 8 x 60mm throttle bodies. A very clean design with the injectors sitting in the heads. Runner length was exactly determined to make max. use of resonating air columns ramming in a lot of fill over standard design manifold hitting that rpm band where the currently installed cams make most power. New intake surface will be almost 100% over the Mercury dual throttle body stock intake. I am still chewing on actuation of the linkage, injector sizes and a matching ECU and harness. Here is the first rendering of the design for calculations and spacing. This is the actual inner surface of the runner length without cylinder heads. The exterior is not considered as of this point. Later it will become a CNC machined billet manifold with flanges for heads and throttle bodies including Carbon velocity stacks. Red are the velocity stacks, purple are the throttle bodies simplified, grey the machined billet manifolds with the transition from longitudinal oval cylinder ports to round 60mm intake ports. Looks like a bottle neck but is just a change in intake runner shape. Yellow is the cylinder head entry.
I can not even imagine how those will sound over 8000 rpm.
Stay tuned...