hey all, what are the specs (power/torque) for both the injected 5lt and 351 windsors in STANDARD form??

Google / search is your friend...
So much info..

im looking into this too, the 351 are twice as strong as 302. Early 302 are stronger than later 302. 351 have larger mains caps but are mostly non roller cam but you can still convert to roller cam just need smaller diameter lobed cam.
Also most 351 will be two piece rear main whichis not desirable, but i may put up with it?!?

Why are you looking into this?

i have looked, but most specs i find are on the mustang 5lt's, i was wanting to compare AUS SPEC 5lt's to the (obviously us spec ) 351

The 1995 Mustang Cobra R had the 351W and made a lazy 220Kw/500Nm

thanks guys

i know where to get two mex blocks, for bout $700 each, but im going down the 351w path i think. More cc's, better bottom end, just need to see how i will fit my explorer intake to my gt40p's on the wider block (due to taller deck height)

I would be going 351 too; apart from the reasons you have listed mexicans still aren't as strong as an aftermarket block and are almost 40 years old now.

With those heads I would be getting as much porting as I can, if you can spare the coin I would even try to get gt40y's as I have a feeling these can be taken a bit further and another manifold; if you're patient they come up for sale fairly cheaply. You could use a spacer with your manifold though.

nah, the gt40y's are the same casting, i had an opportunity to buy them but turned it down. Dont plsn to do too much port work ,msybe mild exhasut, cos its cheaper to buy a set of aftermarket ones. Should be ok under boost tho.

What come up cheap on ebay? Ive seen 351 efi lowers but they dont match the explorer, i think they match trickflow uppers?

Late 5.8 blocks are 1 piece rear main and '94-up blocks are roller type blocks.

5.8 F-series lowers match nothing except the factory upper but do have the same bolt pattern as the excellent 5.0 F-series intake which also happens to match the equally excellent Holley Systemax2 intake. If you wanted to do some heavy port work you can match the 5.8 lower to the holley upper for a good alround intake...probably need a fairly thick phenolic spacer to clear the underside of the upper but you can buy those already.
Other wise the only other stock intake you have is the now hard to find GT40 intake from the '93-'95 Lightning..or the aforementioned '95 Cobra-R.
The Edelbrock performer 5.8 will fit under the bonnet of an EB so it's probably the best choice for a mild 351. A more seroius 351 or a 392+ cuber would need either the victor 5.8 or TFS-R.