[Steve C.]

Paul's picture reminds me of the first early polished version of the Tomahawk intake.

That intake was developed and brought to market by Ken 'Ace' Brewer at Pacific Performance Racing back in 2005 with input from Dave "Big Injun" Anderson.
They named it the Tomahawk and Professional Products was the manufacturing partner at the time.

At the time their product literature stated "The Tomahawk Intake Manifold is designed to work with any cylinder head up to 300cfm"
They were talking about a 'AS CAST' Tomahawk with no port work.

I bought one of these early polished intakes from Ken at PPR. Never used it on the car, but later I dyno tested it on my current 505 for interest.
The port work and plenum work on that Tomahawk I used was very similar to my Dave Bisschop modified HSD intake.
On my very early 505 combo with its first cam this Tomahawk intake, with 1-inch carb spacer & HP950 carb made about 608 HP.
The Victor intake, no carb spacer & HP950 carb at that dyno session made 642 HP.


.

[Steve C.]

Side note.

Regarding my comments here comparing both the Holley Street Dominator intake and the Tomahawk intake, which where essentially the same, to the Victor intake.
Take it with a grain of salt... obviously much depends on the specific combination involved.
Example, in my situation there was less difference in horsepower between the two intakes with the 462 combo than with the larger 505 combo.

.

[Tim Corcoran]

Steve, it was Dave Bischop from SD Performance that did the port work and provided the design for the foundry that was casting it. Dave was somewhat unhappy with the results he said it could of been much better is the foundry did a better job of following his design.

[4zpeed]

The following info on the Holley Street Dominator was taken from the Weiand catalog:

STREET DOMINATOR® SERIES (SINGLE PLANE): The Holley single plane Street Dominator series was designed
for use in the idle to 6000 RPM range. Engineering designed these intakes to make maximum peak power
without sacrificing the low end torque normally only associated with dual plane designs. Large plenum
volumes and optimized runners make these ideal manifolds for use on stock and mildly modified engines.

Always liked the HSD, my use was and still is a 400 iron headed 4sp, Holley carb and mild to moderate cam.
Makes for a very nice combo on the street, and as Paul K says "If you decide you want to whittle on one".


Frank

[Skip Fix]

Herb Adams used the Holley intake and a Holley way back when not using a factory intake and carb. The Holley intake has more material at the top of the port vs the Tomahawk. I think then they added the EFI bosses they dropped it down.

[mysticmissle]

I like the way the holley almost looks factory. i have one, im going to use on a speedmaster flat tappet 400 build.

[Steve C.]

" Dave was somewhat unhappy with the results he said it could of been much better is the foundry did a better job of following his design."

I can understand why he might of been disappointed. The port work and plenum work on a production as cast Tomahawk intake is nowhere near my Dave Bisschop modified HSD intake. Example, as mentioned the as cast port exit dimensions were reduced to work on a stock iron intake. That and a difference in the runners. Also one runner as cast is particularly quirky, with different widths, its been quite awhile and I can't remember which one. Others have brought that subject up before.

All this said I can personally say it took quite a bit of work to make my as cast Tomahawk intake to come close my Dave Bisschop modified HSD intake. But after the work both produced similar results on my limited dyno testing.


Also note there have been some slight design changes over the years on the Tomahawk intake depending on the source (and foundry ?)
Note Skips comment in his post above regarding the EFI bosses.

Edit: Post from Skip Fix in 2006 regarding his Tomahawk intake runners....
As in another post the #1 and #2, particularly #1, runners/entrance is much narrower than the rest of the runners, some by almost .250".





.

[PAUL K]

The plenum and port entrances got a screwed up between the prototype and the copy when they made the Tomahawk manifolds. It's impossible to make ithe Tomahawk version right without welding. That doesn't mean it's a bad manifold. It just can't be a good manifold without a ton of work. The ported HSD manifold I posted a picture of is about as far as you can go without welding. At that point one has to decide if you'd be better off with a better manifold to begin with.

IMO a great benefit of the HSD style manifolds is hood clearance. They are the same height as a factory manifold. Also I always liked the way it looked.

[4dblnkldude]

I was going to try a HSD before I put an Edelbrock torker on my 455 in my firebird. New I want a HSD!

[4zpeed]

Agreed, hood clearance is a real plus for some and a nice looking intake as well, fully dressed or in its slinkiest sexy form, underrated for the original intended use IMO.

Always thought HSD's greatest attribute was in design, a single plane that offered the benefit of performance right off idle to 6000 rpm, appealing for a street car. Of course, the more you whittle on it the more that goes away unless you're adding cubic inches, as mentioned really does depend on one's own particular build or intended use.

Again, I use it on an iron headed 400 4spd, Holley 780, Voodoo 703 and full length headers, couldn't be happier. Many shy away thinking they'll lose bottom end performance, can't imagine a 455 having issues off idle. I see you're planning on using a Quadrajet, here are some results from one of Cliff's tests, pretty sure he's using a Quadrajet.

"As we have mentioned previously, the iron intake has made the quickest runs at the track, in ET only. The highest MPH was obtained with the Tomahawk intake, so is shows potential.
The real interesting part of the testing was on the street. Even with the ET Street's in place, we don't hook up all that well, at least below about 10mph in low gear. This allows the engine to rev quickly into the "good" power, as it is not heavily loaded for very long at low rpm's.
We tested all the intakes on the street, prior to drag racing them. They rank in the following order: Tomahawk, HSD, RPM, Iron."
(http://psp.aquacomp.net/topic.asp?TO...29&whichpage=2)

The link has been broken for years not sure where it was posted memory fails me.


Frank

[promptcritical]

Is there a square bore version of this manifold?

[slowbird]

Originally Posted by promptcritical

Is there a square bore version of this manifold?

No, spread bore only.

[Steve C.]

Put a 1050 Dominator on one


https://forums.maxperformanceinc.com...ntid=19553&d=0

Dave Bisschop built that intake for me many years ago.


.

[4zpeed]

That's purty!



Frank

[PAUL K]

Originally Posted by promptcritical

Is there a square bore version of this manifold?

Originally Posted by slowbird

No, spread bore only.

The carb pad was the same on all HSD manifolds it accepted both square bore and spread bore carburetors

[Skip Fix]

herb Adams used a square bore on them way back then.

My Houston friend Joe Parish has a Dominator version on his 63 tempest. he did not like the driveability of the Dominator so I used a Braeswell 4150 baseplate that took 4500 bolt pattern and put a 1000HP in it with a blended spacer I made. Fits under a stock hood!