[Jay S]

Everything from SM is cheap entry level copies. Metallurgy and quality varies. Go on E bay and buy a 40 year old HSD intake, it will be better than anything SM offers.

[Dragncar]

Originally Posted by Jay S

Everything from SM is cheap entry level copies. Metallurgy and quality varies. Go on E bay and buy a 40 year old HSD intake, it will be better than anything SM offers.

While the HSD is a better made intake the Tomahawk will outrun a as cast HSD.
I did some drag strip testing years back with the old TRW 455 and as cast 96 heads. The Tomahawk was better than 2 tenths quicker than the Holley.
My Tomahawk was touched up by SD a little though.
And the Tomahawk got the car down to 11 flat with the HO heads and SR cam. Its a really good intake for pump gas 455 street engines IMO.
The Warrior outran them all.

[Jay S]

Originally Posted by Dragncar

While the HSD is a better made intake the Tomahawk will outrun a as cast HSD.
I did some drag strip testing years back with the old TRW 455 and as cast 96 heads. The Tomahawk was better than 2 tenths quicker than the Holley.
My Tomahawk was touched up by SD a little though.
And the Tomahawk got the car down to 11 flat with the HO heads and SR cam. Its a really good intake for pump gas 455 street engines IMO.
The Warrior outran them all.

I think that is very accurate info for how the HSD manifolds compared to a Tomahawk. I recall Steve C had a worked over HSD that did really well on the one of his engines when they dynoed it.

A friend that is a machinist said the SM intakes he came across were soft, like a powered metal, broke easy, and would make a ringing sound when hit (an original intake just makes a thud noise when hit). But that probably doesn’t describe all SM intakes, their metallurgy seems like it varies widely. Soft on one thing, then on something else you”ll have grade 8 washers shatter when you tighten bolts up. People on here that like the cheap SM heads try to give SM more credit than deserved. They sell some really low grade junk.

[Steve C.]

Holley Street Dominator intake on a previous pump gas 4.210 stroke 462cid street engine.
This intake was modified by Dave Bisschop.
The port entrance opening was about 2.300" tall, and properly port matched to the cylinder heads in use with some runner blending.
It used my custom HP950 carb.

HSD / no carb spacer:
577.9 hp at 5700 rpm, 581.0 ft.lbs. at 4400 rpm.

HSD / 1/2" open spacer:
589.4 hp at 5600/5700 rpm, 589.0 ft.lbs. at 4600 rpm.

HSD/ 1" open spacer:
589.8 hp at 5700 rpm, 590.8 ft.lbs. at 4400 rpm

Not too shabby considering it has the ability to approach a Victor intake.
With the same engine & carb my Victor intake with 1/2" carb spacer made 600.9 hp at 6000 rpm.

The only testing with the Tomahawk was with my 505 engine with an early camshaft.
This was an original production design Tomahawk introduced by Ken Brewer.
Port work was similar to my Holley Street Dominator intake above..

Here are were three intakes tested with this engine:

Worked Tomahawk intake

w/1-inch open spacer / Holley HP950
630 ft.lbs tq at 4400 rpm
611.6 hp at 5600

Dave Bisschop Holley Street Dominator intake

w/1-inch open spacer / Holley HP950
638 ft.lbs tq at 4400
618.8 hp at 5600 rpm

Victor intake

w/ no spacer / Holley HP950
639 ft.lbs tq at 4600 rpm
641.4 hp at 5900 rpm


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[Steve C.]

Regarding the original Tomahawk intake brought to market by Ken Brewer.

For marketing reasons, the port entrances as cast were very small. Be prepared to open them up unless used on unported small ports with factory heads. Also some of the runners need work, they are not straight
Also for those who use a tall gasket you can go as tall as a SCE #128103 intake gasket without welding ( about a 2.3 tall port), BUT there is not much meat at the top with it for sealing.

I suspect all the copy cat intakes of this design with different names are similar.

Skip Fix can elaborate on the goofy runners, I can't recall now.


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