I don`t know if I`m reading something wrong but it looks like the 4.0 V-6 is 65mm where as the 4.6 V-8 is 55mm. What gives?

 

V8 might be dual 55's?

 

I thougt about that but isn`t 110 mm a bit big? What were the 04`s?

 

It is!! Twin 55's, that is!!

 

Thanks for the info.55mm seemed small, but 110 seemed big, but I guess not.

 

Thanks for the info.55mm seemed small, but 110 seemed big, but I guess not. [/b][/quote]
2 x 55mm is NOT the same as a single 110 mm.

Area of a circle = pi x R ^ 2

2 x 55 mm dia. = 4752 sq mm.

1 x 110 mm dia. = 9503 sq mm

 

2 x 55mm is NOT the same as a single 110 mm.

Area of a circle = pi x R ^ 2

2 x 55 mm dia. = 4752 sq mm.

1 x 110 mm dia. = 9503 sq mm [/b][/quote]

 

2 x 55mm is NOT the same as a single 110 mm.

Area of a circle = pi x R ^ 2

2 x 55 mm dia. = 4752 sq mm.

1 x 110 mm dia. = 9503 sq mm [/b][/quote]
Whoa...math lesson......KEWL

 

Remember, we should be comparing 65mm to 2 x 55mm....or 4225 sq-mm to 4752 sq-mm-- the latter being larger.

 

Actually, when you consider the displacement of the V8 vs. the V6, they are almost the same but the V6 throttle body is slightly larger.

V6: 4225 mm^2 / 4.0 liters = 1056 mm^2 per liter of displacement
V8: 4752 mm^2 / 4.6 liters = 1033 mm^2 per liter of displacement

The Boss Hog
(Not sure what that proves . . . . . )

 

Excellent point.

Of course, doesn't the more valves per cylinder help. (Better breathing with 2 intake vavles can make up for slightly reduced manifold breathing?). I understand it is just about airflow -- but I also wonder about other things... are there less turns in the intake, what's the polish/turbulence, length, dia of the master, and so on.

I'm pretty sure that Ford knows a lot more than I do about their engines, and balanced things pretty well ;-)