3.8 or 3.9??

[SteveC]

still doesn't anser my question thou, how much power from a 4.2 v6 engine?? how much power do those engines make in the pickup trucks??

~15 hp, 25-30lb of torque compared to 99+ 3.8's.

 

[97v6Silver]

but if you set it up as a car engine instead of a torqy slow truck motor then it give way more hp, talking different cam, heads, intake...

 

[SteveC]

but if you set it up as a car engine instead of a torqy slow truck motor then it give way more hp, talking different cam, heads, intake...

Well the fact is the heads on a 4.2 are exactly the same as 99+ 3.8, the cam on the 4.2 is slightly more aggressive in some aspects, and the intake flows as well or better as a 3.8.

 

[97v6Silver]

so? it's a bigger motor it shouldn't have the same specs as a smaller one to start with thats why i said need better heads/intakes/cam... read before we speak next time

 

[SteveC]

so? it's a bigger motor it shouldn't have the same specs as a smaller one to start with thats why i said need better heads/intakes/cam... read before we speak next time

You are talking in circles. A 4.2 responds and mods similar to a 3.8. I have no clue what you are rambling about. Your post read as though the 4.2 had better cam, heads, intake.

 

[triggerman]

4.2/3.9 utilize the same, yes the same intake setup, the only difference is the stroke of the engines, 3.8/3.9 are the same, and yes the 3.9 was delveloped for freestar, but it is a tranverse mounted engine in freestar, the intake is rotated 180 drgrees verses the 4.2. I designed fuel rails for each, the 05 4.2, and the 06 3.9, so to put holes in the one year theory, the 3.9 will be introduced in 05 with the exsisting fuel rail that is on the 3.8 currently, then the new one will go one 06 with a commitment of at least 3 years worth of production. the talk of the 4.0 going in the stang has been around since 01, I personally would look for a 3.5 to be the next mustang base engine, not fact just rumored

the only thing I am aware of on the 3.9 to 4.2 that may be different are the cams, the head and intake combo are the same, and the only reason I say the cam is different is because truck engines are normally set up for lower end touque

on another note the 4.6 3v heads are different then the 5.4 3v heads. currently the 4.6 3v is the best of the 3 engines available in 3v configurations (4.6,5.4,6.8) ther 5.4 and 6.8 are being developed by the truck group, with the 4.6 being developed by the car side

 

[SteveC]

4.2/3.9 utilize the same, yes the same intake setup, the only difference is the stroke of the engines, 3.8/3.9 are the same, and yes the 3.9 was delveloped for freestar, but it is a tranverse mounted engine in freestar, the intake is rotated 180 drgrees verses the 4.2. I designed fuel rails for each, the 05 4.2, and the 06 3.9, so to put holes in the one year theory, the 3.9 will be introduced in 05 with the exsisting fuel rail that is on the 3.8 currently, then the new one will go one 06 with a commitment of at least 3 years worth of production. the talk of the 4.0 going in the stang has been around since 01, I personally would look for a 3.5 to be the next mustang base engine, not fact just rumored

the only thing I am aware of on the 3.9 to 4.2 that may be different are the cams, the head and intake combo are the same, and the only reason I say the cam is different is because truck engines are normally set up for lower end touque

on another note the 4.6 3v heads are different then the 5.4 3v heads. currently the 4.6 3v is the best of the 3 engines available in 3v configurations (4.6,5.4,6.8) ther 5.4 and 6.8 are being developed by the truck group, with the 4.6 being developed by the car side

The upper intakes are different between 3.8/3.9 and 4.2's... I assume you know that... but wanted to make sure that is clear. The lower is the same other than coolant line locations. The cam specs are slightly different.

 

[triggerman]

06 3.9 vs 05 4.2 utilize the same part number upper intake. and I am pretty sure it is a 3.8 part number from 03, I will double check that tomorrow. coolant lines in the 06 3.9 to the 4.2 of 05 are slightly different. now current production may indeed be different but the next round of engines they will be the same. Guess I forget I am working on items 2 to 3 years in advance. fact remains they all bolt the same as far as set up, fuel rail bolts to the lower and the injectors are in the head at a compound angle. that design has been there since 2001, maybe longer

 

[SteveC]

Alright- I thought you were referring to current models.

 

[dastang2]

tq is what you want anyway instead of hp. the trucks those engines are in are peppy machines with the manual tranny behind them.

 

[01White5spd]

Yeah my brother had an '02 F150 with the 4.2L and manual tranny, and it was pretty quick.