I cant help myself I was going to stay N/A for my dirt events but after pulling the head of my GSR parts car and finding little wrong other than a popped head gasket
so the build will go in prob a different direction to most as it has to pull from the bottom of the range

here is the plan the head looks to need so attention to the ports just like sigma and early magna the inner radius is a sharp corner and looks like it needs to be ground back to a larger radius the rest of the ports arn't bad just a bit of cleaning up around the guides
and of cause the seats (and throats ) will be opened up with a nice 3 angle cut and the valves back cut

has any one done much more than this to there ports ?

I have a multi point efi going on

I plan to lift the comp to 9.5 : 1 and leave the boost stock
that should pull better off boost and between an intercooler and an after market computor to tune any bad bits stock boost should be safe at this comp
the tco6 that is on the car has some play and will need looking at
so it may get upgarded after reserch here it looks like a td05-14b might be the go

as for the bottem end its still in the car so I haven't looked inside but I would think the same stuff that I would do to a N/A engine would be the same
polish and shoot pean the rods + fit some ARPs
polish up the crank ( remove some weight ) make up a flywheel about 4 Kg should be heavy enough and fit a good clutch maybe a 7 1/4 tilton single plate
it goes with out saying the balance shafts wont go back in
I will modifiy the sump for more volume as well as baffles to reduce surge
and I will make up an oil scraper

I dont know what sort of power output a build like this will do maybe about 110 Kw atw but off boost to low boost should be better ( more important on tight autocross tracks )

_________________
cheater

GE Sigma 2.6 Improved Production ( 119.5 Kw atw N/A )

projects
LJ Torana Historic Touring Car
1981 E21 BMW 323 JPS
Type 7 clone sports car