nuuk

I run a Quickfuel 600 vac sec on my XF ute with similar specs,

Just get a 450 quick fool.

Late reply woops. But Yeah using the new version of the aussiespeed manifold, will be running it east west. Not worried about the cost of carby too much as I'd rather just buy the right one the first time. I was thinking for more drivability on the street that a vaccum secondary would be better and still be able to have a bit more top end with a higher cfm carb. 

are you using the big plenum manifold or smaller one ? ive been thru this b4 and would suggest the 450 quickfuel double pumper,i tried a 650 it does work but a bit of a overkill unless seriously racing ,and are you running the carb east west or nth south,all those carbs will work if i had my time again i would run a 600 pumper holley or the 465 quickfuel is a very nice carb on a back yard tune it 212hp at the wheels with plenty of room for more tuning says the dyno guy,he reckons could have got it to 240 approx,same 3.45 gears single rail ect.

Hey guys just wondering what size carb I should be looking at for my crossflow, not finished yet but here are some simple specs.
 
Crow 14672 cam, 231@50 .550 lift 108LSA
10.8:1 comp 
E2 Head flowing 235cfm
C4 with stall
3.45 diff
And all the other goodies and supporting mods.
 
Will be using an aussiespeed manifold but not sure on carb, something around 600cfm I'm assuming just from looking at others posts.
Any other advice is appreciated.

The crossflow in my XFN (Nissan) ute, had 6thou clearance on the mains... lol!
Still ran quite reasonably, too.

crossflows will run with sand in the oil, but it's not ideal on a rebuild spec

Hi mate, "general" rule is 3/4 to 1 thousandths of an inch per inch of shaft diameter. 0.0075" - 0.001" So, a 2 inch journal can have 0.002" of clearance. 
As I said, this is a "general rule", as things like race engines, boost, revlimit can come into play. Stick with a well known brand like ACL, Clevite, Federal Mogul etc.....they aren't that expensive considering what they do.