you could go with a 351 deck height a 4.125 bore and the 347 crank.
the extra deck height will let you use a longer rod.

With Clevo mains...
Keep in mind with turbo engine?? You'll have more torque and power than you need.. Keep things safe and let boost make your power..
Fords F303 cam has made over 1000 h.p so specs around cam specs should work.. Lift with sfa overlap..
I used 4340 crank, Oliver rods and C.P pistons 27 cc dish with 61cc heads.. I wouldn't run my compression though.. 20cc would do fine..Or 8.5 compression..

No you can't, there is nearly 0.500" difference in main journal size between a 302W and a DART/SVO (Cleveland) main. Standard 351W is bigger again.

IMHO follow EBXR8380's advice keep between 8.5-9.0 compression, the boost at a moderate level and 'over engineer' the strength level for longevity.

Since i want this thing running in the near future, and funds don't seem to be flowing as well as they should, i'm considering buying a decent rotating assembly, some I beams and low comp pistons to slip into my windsor block i already have ready to go, most probably keep it 302ci, use ARP bolts and make a fairly tough little windsor, while i build the DART on the side sometime in the future...

because looking at the collection of parts in the shed sitting doing nothing is rather depressing. sorry to disapoint you all, but i want boost sooner rather than later, i know it will be risky with the block, but with 6psi im hoping it will be ok..

EBXR8380 has been a big help in previous thread's, so running with that info, i'll see what i can do..

i'd rather have something running, which i can fiddle and tinker with than parts sitting in the shed looking pretty..

is it worth getting the block converted to 4 bolt mains? what sort of price am i looking at, and will it throw a maincap before it cracks in the valley

thoughts ppls?

Build a stealth std 351 block they can handle any sort of abuse and power than a 5.0 would on the street..
On www.turbomustngs.com there are heaps of high mileage 5.0 with turbo fitted along with good tune..
That with std rotating assembly..
My old 5.0 run well at 270 rwkw with std 9.0 compression it was very responsive!!
That engine still lives and never died..
The mains webbing on roller blocks is very thin and fitting 4 bolt mains will only weaken them..

Some things sound conficting?? But you could build it thinking .. Well if it blows ?? it blows !!.. Nine times out of ten.. They hold together.. Its the rpm AND abuse that splits roller blocks...
270 RWKW in turbo or forced induction is like another 100 kw N/A due to lower rpm torque and power levels.. Higher final drive gives good economy when cruising also..
Leave it std stroke and let the turbo's make the power ???

i've actually been looking for a good 351w for rebuild, but they are fairly rare. Unless i point my attention to the US. 302w seems like a good option as the conversion will be easier and also parts are easier to come by.

Building up a 302 will also give me some well needed experience before attempting the DART build.

I'll just prey the b**ch holds together! which sounds like it will if done properly.

thanks again for your help EBXR8380..