Ford Mustang Forum banner

Status
Not open for further replies.
1 - 13 of 13 Posts

·
Registered
Joined
·
621 Posts
Discussion Starter #1
Hey guys so I'm not super mechanically inclined so I need some clarification. What exactly are the differences, advantages and disadvantages to having a 3V motor or a 4V? If I were to do an engine swap which would you recommend and why? Thanks guys
 

·
Registered
Joined
·
588 Posts
That means that each cylinder has 3 or 4 valves. The 4 valve motor should breath better since it has 2 intake and 2 exhaust valves. I'm not exactly sure how the 3 valve set up on the 4.6 GT engine is set up, but it's either 2 intake and one larger exhaust valve or vice-versa. I haven't done much engine work in a while.
 

·
Registered
Joined
·
621 Posts
Discussion Starter #3
so overall the 4V would be a better engine? since it breathes better meaning its probably putting out more and is more efficient?
 

·
Registered
Joined
·
10,877 Posts
The 4V only breathes a little better on the exhaust side. Now are you talking about the 4.6 or 5.4 4V? The older mustangs have the 4.6 4Vs and the GT500s have the 5.4 4Vs.
 

·
Registered
Joined
·
621 Posts
Discussion Starter #5
im talking about a current 4.6L in the 2005+ models
 

·
Registered
Joined
·
124 Posts
they have a 2 intake Valves and 1 bigger exhaust valve, the 4V breathes "LITTLE" More.. our engine is more developed
 

·
Registered
Joined
·
621 Posts
Discussion Starter #7
sooooo is it pointless to pay for a current 4.6L 4v? :headscratch:
 

·
Registered
Joined
·
2,829 Posts
4.6L 4-valve engines in Mustangs:
'96 to '98 SVT Cobra 305hp and 300 lb-ft with forged crank
'99 and '01 SVT Cobra 320hp and 317 lb-ft with forged crank
'03 and '04 Mach1 auto 305hp and 320 lb-ft with cast crank
'03 and '04 Mach1 manual 305hp and 320 lb-ft with forged crank
'03 and '04 supercharged SVT Cobra 390hp and 390 lb-ft with forged crank

versus '05 to '09 GT 4.6L 3-valve engine 300hp and 320 lb-ft with cast crank

The 3-valve engine was a big improvement over the 4.6L 2-valve (215hp in '96 and '97, 225hp in '98, 260hp from '99 to '04). It is more compact than the bulky 4-valve motors and produces about the same power as all except the supercharged terminators (of course). There are far more aftermarket parts available for the 3-valve than the various iterations of the 4-valve 4.6L, espcially since most of those 4-valve heads and intake manifolds are NOT interchangeable. The only real advantage to the 4.6L 4-valve is the forged crankshaft (except in Mach1s with automatic transmissions).
 

·
Registered
Joined
·
621 Posts
Discussion Starter #9
4.6L 4-valve engines in Mustangs:
'96 to '98 SVT Cobra 305hp and 300 lb-ft with forged crank
'99 and '01 SVT Cobra 320hp and 317 lb-ft with forged crank
'03 and '04 Mach1 auto 305hp and 320 lb-ft with cast crank
'03 and '04 Mach1 manual 305hp and 320 lb-ft with forged crank
'03 and '04 supercharged SVT Cobra 390hp and 390 lb-ft with forged crank

versus '05 to '09 GT 4.6L 3-valve engine 300hp and 320 lb-ft with cast crank

The 3-valve engine was a big improvement over the 4.6L 2-valve (215hp in '96 and '97, 225hp in '98, 260hp from '99 to '04). It is more compact than the bulky 4-valve motors and produces about the same power as all except the supercharged terminators (of course). There are far more aftermarket parts available for the 3-valve than the various iterations of the 4-valve 4.6L, espcially since most of those 4-valve heads and intake manifolds are NOT interchangeable. The only real advantage to the 4.6L 4-valve is the forged crankshaft (except in Mach1s with automatic transmissions).
alright thanks gary ill stick with a 3V when I go for a motor swap.
 

·
Registered
Joined
·
2,693 Posts
No need to swap to the 4v unless your gaining displacement with it (going to a 5.4).
 

·
Registered
Joined
·
621 Posts
Discussion Starter #12
You can go with ported heads and cams instead. :bigthumbsup
sounds like a good trade off :D
No need to swap to the 4v unless your gaining displacement with it (going to a 5.4).
I don't think I'll be getting a 5.4 at the most probably just a 302 cuz I want to do track (road racing) not drag so I won't need quite as much power
 
1 - 13 of 13 Posts
Status
Not open for further replies.
Top