2V, 3V, and 4V?

[Fordzilla80]

Okay guys, I'm behind on the newer motors, especially when it comes to the 2V etc designations of an engine. I'm pretty sure 2V means two valves, referring to the exhaust and intake valves. But what about 3V and 4V? If those are extra valves, what are they for?

 

[blacksnapon]

Okay guys, I'm behind on the newer motors, especially when it comes to the 2V etc designations of an engine. I'm pretty sure 2V means two valves, referring to the exhaust and intake valves. But what about 3V and 4V? If those are extra valves, what are they for?

Yep, three valve (2 intake, one exhaust) four valve (2 each)

 

[flareside_thunder]

The faster the air gets in and out the more efficient the engine and the more power it's gonna make. Would you rather drink through one straw or 2 to quench your thirst?

 

[agjake11]

The faster the air gets in and out the more efficient the engine and the more power it's gonna make. Would you rather drink through one straw or 2 to quench your thirst?

this about sums it up.

 

[Fordzilla80]

this about sums it up.

Agreed.

Thanks Vince and JR!

 

[Alvin in AZ]

Agreed.

Since I'm contrary as hell, I don't agree.
And neither did the FT engine engineers.

So, bigger is not -always- better.

They put smaller intake runners and smaller
valves on the 361FT and 391FT than they
did in the 360FE and 390FE.

In '75...
330MD+XD, 361FT, 391FT valve head size...
Intake = 1.745"
Exhaust = 1.500"
360FE, 390FE valve head size...
Intake = 2.022"
Exhaust = 1.551"

Butthead in AZ

 

[SuperCab]

That was for better low RPM performance... Keeps the air velocity up at old HD truck RPMs (i.e. really low 850-2500). For modern hi rev mod motors, the extra valves are much needed.

the 390 p/u engine had bigger valves for bigger revs.

 

[Alvin in AZ]

That was for better low RPM performance... Keeps the air velocity up at old HD
truck RPMs (i.e. really low 850-2500). For modern hi rev mod motors, the extra
valves are much needed.
the 390 p/u engine had bigger valves for bigger revs.

x2

Alvin in AZ

 

[SuperCab]

I like to be contrary too

 

[Fordzilla80]

I like to be contrary too

Pssh, you just like icles.

 

[O'Rattlecan]

Yeah from what I've read is that the benefit from more valves is due more to the ability to turn more RPM's.

Ryan

 

[flareside_thunder]

yea.......efficiency