400 intake manifold
New User
Joined: Oct 2002
Posts: 13
Likes: 0
From: Brenham u.s.a.
400 intake manifold
I have friend that has a 56 ford truck with a 400 . the motor runs on 92 pump gas and runs 7.50"s 1/8 mile with 1.60 60fts.
the motor has a comp roller that is 260 @ .050 650 lift and 110 lc
850 dp 2 bbl heads C-6 with a 10 converter 3500 stall.
the intake manifold he runs is very small (holley street master)
he shifts the motor at 6500 and runs very well.
holley made 3 versions of the same style manifold wich fits the 351 c
and can be used on the 400 with spacers.
street master idle to 4000
street dominator idle to 4800
strip dominator 4500 to 8500
he said that the small runners promote air speed wich in turn effects
velocity and torque
if that manifold will support 400 cubes and 6500 rpm
the street dominator wich fits the 351 c 4 v heads but has the runner size of the 2 bbl heads and a flange that will make it work on 4v heads should run to 7500 with a roller the same size on 351 cubes and speed up the air and build torque.
would this be right?
madmanmike
the motor has a comp roller that is 260 @ .050 650 lift and 110 lc
850 dp 2 bbl heads C-6 with a 10 converter 3500 stall.
the intake manifold he runs is very small (holley street master)
he shifts the motor at 6500 and runs very well.
holley made 3 versions of the same style manifold wich fits the 351 c
and can be used on the 400 with spacers.
street master idle to 4000
street dominator idle to 4800
strip dominator 4500 to 8500
he said that the small runners promote air speed wich in turn effects
velocity and torque
if that manifold will support 400 cubes and 6500 rpm
the street dominator wich fits the 351 c 4 v heads but has the runner size of the 2 bbl heads and a flange that will make it work on 4v heads should run to 7500 with a roller the same size on 351 cubes and speed up the air and build torque.
would this be right?
madmanmike
Senior User
Joined: Jun 2002
Posts: 423
Likes: 0
From: Oklahoma
400 intake manifold
I'm no expert and I've no experience with Holley intakes, but I would think that the intake charge would have good velocity thru the manifold but velocity would drop once it entered the very large 4V ports with possible mixture separation as a result. You'd also have a port-mismatch that would cause a lot of turbulence, wouldn't you? The other drawback, IMO, would be the adapter plates providing additional places for a possible vacuum leak if they warp or don't seal correctly. It was common practice for folks to use epoxy or some sort of filler material to shrink the 4V ports to near 2V size while raising the port floor to give a better angle of approach to the valve.
