348 409 Speed-Port Intake, Machined & Installed !


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I like the one on the far left that looks like it has a pad for fuel injectors to go.
Either way, congrats on getting through the work and effort!
oh oh.... the votes are still coming in... and the weight is shifting a bit...
Hope these THESE ballots aren't "fixed":p.... we'd HAVE TO stamp some GM part numbers in there;)

I better make up my mind pretty soon:rub

Yes, maybe injector bungs... there's room.... though I DID have to trim that part a bit after machining this last prototype.


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Just for grins, what about a "fractional" part number, say a one half or five eighths? Just something which turns heads for anyone paying attention? :dunno


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Make sure you use 0-xxxxxx. Makes people think it's a factory experimental part!!!!!!!!!!!!!!!!!!
NO! NO! NO! You can't have 6 x's! That's for Nascar experimental only. 5x's is extremely rare COPO experimental and there is no such thing as 3 or 4 x's That leaves 2 x's were experimental for public use and 1 x was on the block itself. Come on guys I thought you knew better!!:roll:roll:roll

Phil Reed

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Wally...........you might know your "x" up to 6........................but I've had a 7X Stetson for years!!!!!!


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The 3rd on is going to have 3 deuces right? One that flows better than the factory stuff. Then the 4th one could have 2 4's on it. Great idea Aubrey! I'll put in my order for the first 3x2 manifold you come out with.:deal
3 deuces ( triple two barrel ) ?
There probably would be a call for that... especially one that could feed a 450+ inch engine to 6000 RPM, and a large port available as well... but that won't be me.
2 4's ?
Offenhauser, and GM had that looked after years ago. For those wanting the high end 2X4, Lamar Waldon's intake would be tough to compete with. In between, we have the Edelbrock, which is an excellent compromise.... so those enthusiasts who are drawn to the "4 speed, dual quad, positraction 409" sceneraio, are all looked after. Add to that, I believe that our own Bob Walla, is working on a tunnel ram.
That leaves me, with the most expensive manifold project in history:crazy.... and it's just a single 4 barrel:yawn
Naah.. the third one that I'm looking at ( in two different models ), would be very aggressive, raised runners, one using a Dominator style carb.... tentatively dubbed Speed-Port 8000 rpm. The other basically the same, but using a standard carb flange... called Speed-Port Super Stock ( yes, actually intended to be legal in NHRA/IHRA Super Stock vlass ).
Just ideas at the moment.
These first two are going to have to show some movement first:pray


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At $1600 for the Walden it would be easy to compete with. The GM blows and the Edelbrock is only marginally better. I haven't heard anything about Bob's intake, but for now, there definitely seems to be a vacuum in the 2x4 intake market for anything more than a cruiser. Just my opinion.


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I just love the look of 3x2's but the performance is seriously lacking. If they came out with a aluminum 3x2 intake that used Holly 2300 carbs then I would buy that.
Just about anything would be better than what the factory had.
Geez, Dan... at $1600 for Lamar's intake, is just a spit in bucket, compared to what it cost me to do this one:crazy
Cecil, Wally... I know, it would be cool... but that's a complete re-design... even with my own plan and drawings, it would cost thousands ( boy, have I learned my lesson ) to create the new pattern. Just not in the cards for this feeble player.
Just a quick update here.
Spent the ;last few days getting this engine back together. I ended up doing a lot of preparation to the "333" truck heads. Port and bowl work, 2.06" / 1.735" valves, Comp springs. 7/16" screw in studs, roller rockers.
Here's a picture of the engine as I was assembling:

And here's the REAL DEAL !!.....

Yes, this first Speed port intake manifold, is actually installed, and running ! !
Here's a simple video taken a few hours ago:
409 Chevrolet with Speed-Port-6000 intake manifold

Cam is now broken in. Next, must install the inner valve springs, and do a hot valve lash adjustment.
Might look at the mixture as well. Cabruretot in use, is the 700 Holley from my truck, which has been jetted down. Spark plus are WHITE.

If things go right, I'll road test tomorrow.


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Great to see Aubrey:clap. Will you be doing a back to back swap with a stock manifold on the dyno? Any 1/4 mile blasts possible?