[powersrj]

I want to start a new mustang build and im on the fence between starting with the 5.4 4v block or the 5.0 (Modular Boss) block on Ford Racing. I have asked the Ford Racing tech team about this block and they say it is NOT just a bored 4.6 and highly recommended it. My question is does it really out perform the less expensive yet way heaver bulky 5.4 liter?

Ford Racing Performance Parts [M-6010-BOSS50*]

[ForestGRN_Ghost]

well ford uses a 5.0 cammer motor in there gt40 for FIA GT. they took the standard 5.4 out. i guess if your doing some serious racing and you have the money. do it up.

[zigbigadoru]

or you could get an aluminum 5.4 and have the best of both worlds. lighter weight than the 5.0 cuz its cast iron and more displacement......YAY!!!!!!

[powersrj]

Well i dont have the money to go alluminum. Thats tones of cash. I could spring for the extra $900 for the 5.0 but if it truely isnt going to give me any more performance than that dirt cheap 5.4 liter i dont see why i should spend more cash for less displacement and possibly less horsepower...but i dont know i mean i am up in the air.

[Thumbie]

this actually is a pretty tough one. if money wasn't an issue i'd build the 5.0 with forged internals and boost it. but since it is, I almost want to say 5.4 and use the extra cash to accomodate it and such.

[powersrj]

Well the plan is to be forged and boosted either way...so on that which block would you guys choose?

[OneBadNotch]

Personally man, i would go with the 5.4. Im actually doing a 5.4 in my 90 lx, and you can go a lot further for your money. I had a 5.0 in it and it was running tens with nitrous, but now ill be running low 9's on just motor. The amount of torque in the 5.4 is immense. And i got my 5.4 and transmission for a little over 1000. With the turbo set up and everything in the motor, ive only spent about 8000.

[zigbigadoru]

well im very preferential to the 5.4 just cuz you get to do it yourself. also if you decide later on to upgrade your heads you can always grab a pair of r heads or gt500 heads and get like 400 hp N/A. so yea.....oh and did i mention you can also bore the 5.4 out as well to achieve 5.5L of displacement and thats if you dont resleeve it. but thats just me.

[OneBadNotch]

yea, i agree. It easy to achieve a good amount of horsepower from a 5.4. And if you want to do it the cheap way and go to a junkyard and get a set of heads of a lincoln mark 8. They are the b heads, the same that come on the 96 cobra's. But my 5.4 is estimated to be pushing close to 900 horsepower at 25 psi, but i haven't completely finished it and it took it the dyno yet. So like i said, its easier and cheaper to build.

[ForestGRN_Ghost]

with the money you save buying the 5.4.. you have the extra cash for the intake manifold. that its going to require. and possibly poly motor mounts if you dont already have it

[HBK_2007]

i vote buying a used lighting short block (5.4 factory forged) and droping it in then save up for a forged aluminum 5.4

[powersrj]

i could do that...i just dont know how much benifit these $3,000 dollar bare alluminum blocks are in the grand scheme of things...sure you save on weight but i mean if your cranking out 700+ horse power on the street what does it matter. I just am really curious how this modular boss 5.0 block fordracing has. It fits up to everything just as any other modular block but its about 900 more dollars new than the 5.4. Its suppose to perform fantastic though.

Either way the block will be forged with 4 valve heads slapped on, i just think for the money i could get away with the 5.4 if this modular 5.0 isnt that slick.

[86er]

02 and up NVH block 4v heads and hang a 91mm off the side and watch and lay waste to all that is near you

[86er]

Originally Posted by HBK_2007 i vote buying a used lighting short block (5.4 factory forged) and droping it in then save up for a forged aluminum 5.4

450ish they start puking rods out the side

crank is only thing worth a damn in that motor and any truck crank that is 8 bolt fly/flex is forged from factory fyi

[HBK_2007]

Originally Posted by 86er any truck crank that is 8 bolt fly/flex is forged from factory fyi

didnt know that. whered you find that out? is that just the 5.4s or the 4.6s too?

[86er]

Originally Posted by HBK_2007 didnt know that. whered you find that out? is that just the 5.4s or the 4.6s too?

I have a friend who builds 2500hp plus mod motors for racers. The 8 bolt cranks are just another modular piece that ford over did and makes easier for these motors to make north of 1k hp

if its got 8 bolts its factory forged

[powersrj]

Ok so im a little confused on 86ers comments and im trying to keep up. I was lost at the NVH? and than something about 450ish they spit rods out the side?? What blocks and set ups are we talking about??

[powersrj]

I think the 5.4 liter out the Lightning has i beam rods and the Ford Racing short blocks they are celling have H Beam. I think?

[HBK_2007]

Originally Posted by 86er I have a friend who builds 2500hp plus mod motors for racers. The 8 bolt cranks are just another modular piece that ford over did and makes easier for these motors to make north of 1k hp if its got 8 bolts its factory forged

oh really. thats nice to know. whats the issues one would come across puting a 5.4 crank in a 4.6, other than needing shorter rods

[86er]

that I dont know, tryin to stroke it? or just a forged factory crank? If so use a cobra crank