ORIGINAL: 2000Si

first, whats the stock bore and stroke of a 99+ 4.6? 3.55 x 3.54

next, boring it over, how far can you go over? .020, .030? .020 is ideal but they sell .030 and shm sells .040 (tarded to do that) pistons

Do you think by boring and stroking a 4.6 you could between 5.2-5.7 liters out of it? 5.1 that I know of, unless its an aluminum block - stroking is kinda frowned upon (honestly) - the consensus is to either get an aluminum block and do a big bore (I think they use a spray bore for them) or nothing - even though no machining whatsoever is needed for stroking

~ how big are the intake and exhaust valves? In inches or CMs
~ what kind of manifolds do the GTs use? (single plane, dual plane, tunnel ram, individual runner, etc)
~ what kind of flow does the stock IM put down in CFMs? My guess is either 300 or 400 CFMs, but I dunno.
~ what kind of lifters do they use? hydro flat tappet, solid flat tappet or roller solid/hydro lifters?
~ what kind of lift and duration does the cam produce on the stock valves?

ORIGINAL: mdvaldosta

1. 1.752/1.417 (source info from http://www.modulardepot.com/modspecs.php)
2. I dunno what kinda intake its considered, it doesn't fit into any of those categories... its a single plane type that performs like a dual plane as far as powerband is concerned.
3. Not sure about the intake, but a stock plenum/throttlebody flows about 450cfm so thats all that can get to the intake
4. Roller hydro
5. .505/.534-inch lift Duration (I/E) @ .050" 186/194 (source was http://www.modulardepot.com/modspecs.php)