My 2001 Mustang has 190,000 miles on it and i drive the mess out of it everyday.But my fun has come to close because i am pulling my 3.9 for my 4.2 bored over 40 over! so that is a 4.6 v6 and i have tma twin turbo kit rdy to bolt-on.

my parts list is about a mile and half long. but what numbers do u think i will be throwing out on a dyno with out a tune and with one.

j-mod shift kit
4.2 (over .40)
2-t3/t4 turbos (starting at 5-8 psi)
2.5" true dual exhast
3.8 windstar intake
stock rear end with t-lock(for now)

 

I bet roughly zero. Taking a 3.8L block with 4.2L crank outto 4.6L displacement means cutting into a LOT of the cylinder wall. Too much to run safely, and far too much to add a lot of boost to.

However, if you used a 4.2L set up and tossed in the TT set up from Andy, I'd go with a touch over 400 hp. But much more than that and you'll need a new tranny and rear end.

And you HAVE to tune it. Swapping out fuel system parts requires a tune, otherwise you won't make crap at all.

 

it is a 4.2 block not a 3.8 block.

i have seen justin's twin turbo 4.2 from tmamaking 610rwhp and 570wrtq at 5800 rpms at 16 psi.

Got gt fuel pump
and injetors!

 

They're the same thing.

 

J's (Jeromie - not Justin) set up is the one making that power level, and he has far more ofa set up than you posted you will have. His is also not the TMA T3/T4 hybrid TT set up. J is using much larger turbos for that power number (GT30s if I remember right) and a lot of custom piping the TMA did for him (one and only type set up for now). He also runs a built tranny, built 8.8 rear with 31 splines, a custom fuel rail he made himself, 83 lb/hr injectors and a host of other stuff.

I'll stick to my original guess.

 

I'm gonna go with failure as my guess.

You know what it takes to get a 3.8L to 4.6L? Its not worth offset grinding the crank and owning your cylinder walls.

Also:
T3/T4 is a very general statement, do you know how many different t3/t4 turbos their are? with different a/r? How about being more specific?!