11/12/2025
MargaretandGeorge Phillips two years ago came to us with there mint holden HZ for some power upgrades so we ported and fitted a set of yellaterra heads and installed new camshaft and bigger carb .. after we tuned it up on the dyno we seen a solid 351hp@the hubs from the 308ci stock bottom end iron lion πͺπͺ..
Fast forward a year and a half later Margaret informs George that the holden needs more power ! ..
So we built up another 355ci short block with a dished pistons to keep the comp ratio the same ... we swapped over all the other hardware to the new short block ..fitted the engine and loaded it onto dyno .. with some header collector mods and tuning we finished up with a nice 427hp and heaps of torque ..
A great combo for a street car with strong midrange with..
..... 355ci
..... flat tappet cam
...... 650cfm carby
...... dual plane intake manifold ..... iron lion πͺπͺ not LS swapped ..