DeTomaso Mailing List: April 2000, Message #306

> The F351-4V was designed by Edelbrock with the aforementioned port
> mismatch.  
> It is designed to promote port velocity for increased low end torque for
> normal street 
> driving (as eluded to by the illustrious Jack DeRyke).  But I do disagree
> on his 
> statement that the engine would be limited to 5200rpm.  When I used the
> F351-4V 
> on my otherwise stock engined 74 Pantera, it would rev to 5900rpm (at
> least until 
> the valve springs started to go).
> 
The one on the modified 4V in my '66 Mustang has turned 7000 rpm numerous 
times.

> I also don't think it is the same port size as on a true 2V manifold, I
> think it is 
> somewhere in between the two extremes.
> 
Correct.  The 2V version has an oval port and it's sized to match the oval
port 
of a 2V head.  The 4V version is somewhat larger and shaped differently.  If
I were
porting a set of 2V heads, I'd look into what it would take to port match to
the 4V 
version (or just port match to the Xcelerator 2V which also has larger ports
which 
is what I did). 

Dan Jones