(suspenseful music)
- Manifolds, here is that dual plane that we just ran.
And you can look in there and kind of see
why people think that these things don't
run well on nitrous or potentially don't.
They have two separate levels inside them.
Each half goes to four cylinders in the engine.
These things tend to make more torque
and less top end horsepower,
whereas what we're about to go to
is the Victor single plane intake manifold.
This is a nice big hairy manifold
especially when ported.
I think on our 383 it's really not the manifold
that I would choose for running down either the street
or the drag strip but, it is going to answer those questions
about fuel distribution issues,
and whether nitrous makes more power on this style
of manifold so,
we're going to go and install this pooch right now.
Just pull this guy aside.
The cool thing about the big block mopar
is that it doesn't have water in the intake manifold
so we're going to be able to just pull off
this one and slap a new one on there like nothing.
Oh man, this manifolds hot.
(laughing)
That is no good.
- How come it has so much manifold leak?
(calming music)
- [David Freiburger] Kaboom.
(calming music)
- [Steve Brulé] Right on the side of my box.
- Now we're going to have to go fire this thing up
and almost certainly it's going to need a jet change
because of the single plane versus dual plane intake,
we'll run it at A and then come back and spray it again.
- I have to make the observation here
that the engine looks much more racy.
- [David] Yeah, too bad that it won't
run that much more racy.
- I know that's the down side.
- Now that single plane manifold is in place
and all tuned up and we also bumped the ignition timing
back to where it was when we ran the dual plane, natural
aspirated so what you're about to get is
a clean AB test of the dual plane manifold
versus the single plane manifold.
(engine revving)
That's the most horsepower we've seen
so far naturally aspirated at the cost of torque
which is completely predictable
considering what we're doing.
- [Steve Brulé] Surprise!
- [David] There you go the red is the dual plane,
black is the single plane the dual plane makes
more torque and you get a little bit
more horsepower to the single plane.
Actually Steve ran it higher too it wasn't 65 hundred.
- Dual plane was so I went ahead
and ran it at 300 higher just so it could get to peak again.
- Our new power peaks with the single intake manifold
are 473.1 horsepower and 454.2 pound feet of torque.
You can see really looking at the graph,
it tells a better story then just the peaks though.
You know you're giving up a lot of power below 46,700 RPM.
But what we're really doing here is looking
at distribution issues and nitrous so let's have a look
at what the cylinder to cylinder looks like
with the single plane.
- [Man] It's better but it's not fantastic.
- But will it make more power on nitrous?
- Oo, how do you find that out?
- Let's go squirt this thing, I'm tired
of messing around with 470 horsepower it's boring me.
(engine revving)
The last test, theoretically the good one.
Single plane intake manifold 150 shot,
we pulled the timing back and wack it.
The only thing I'm curious about here
is does it make more power?
And I think it might because the airflow seems
to continue at a higher RPM than the dual plane, yeah.
(suspenseful music)
(engine revving)