New BBM Tunnel Wedge arrived today.

[Joe-JDC]

I received my new BBM Tunnel Wedge intake today, and it looks very clean and well made.  I was surprised at the size of the intake ports because I was under the impression the ports were going to be high velocity and smaller than stock.  They are quite a bit larger than the original C8AX-A Ford Motorsports intake, and I wanted to see how it compared with the original in flow numbers.  Standard procedure to tape the seven ports not being flowed, block off the power brakes fitting, and use two open spacers with tapers to reduce turbulence when flowing.  Here are the flow figures from a Ford intake as cast, and the new BBM as cast.

Ford C8AX-A tunnel wedge

1.     374.35
2.     385.94
3.     372.57
4.     365.44
5.     370.79
6.     369.01
7.     380.59
8.     380.59 for an average of 374.91 cfm.

BBM tunnel wedge as cast:

1.     478.56
2.     484.54
3.     479.76
4.     472.58
5.     466.60
6.     479.76
7.     483.35
8.     496.57 for an average of 480.215 cfm

Flowed on SF-600 in air conditioned room at 70*, 38% humidity.  10-19-2016  Joe-JDC

[Drew Pojedinec]

Wow.....
So, fantastic intake for the full on racer... maybe not the best choice for the street/strip guy.

Happy I snagged my BT 2x4 MR instead of waiting for the tunnelwedge (I too was under the impression it was to be a high velocity intake)

Thanks as always for the information sir!

[bsprowl]

Wow indeed.  Over one hundred CFM average increase. 

Probably a bit much for our 390 GTs.

lol

Bob

[Katz427]

Question for Joe or anybody really " are there any medium riser port heads that can flow ~ 400cfm ?

[e philpott]

sweet intake for a big incher .... I guess some future track and dyno testing  time will tell the rest of the story

[jayb]

Question for Joe or anybody really " are there any medium riser port heads that can flow ~ 400cfm ?

I don't know of any.  My high riser heads just snuck in to the 400 cfm range; best medium riser's I've seen have been 360-370.  Some of the Pro-Port stuff may be better, but they are not really medium risers...

[jayb]

Here are some pictures that Joe sent me of the new BBM tunnel wedge, compared to an original:

[My427stang]

I wonder how it compares in volume?  Maybe an opportunity to fill the floor and run a 375-400 cfm charge higher in the port even faster that the stock one and mate it to a good set or worked FElony heads?

Might get something that brings the airflow in at a better position to make the turn at the valve, but still flows big numbers.  Sort of like an "upper-half" med riser

[e philpott]

It will be interesting to hear what Blair says after some dyno pulls

[cjshaker]

I wonder how NHRA will view this as a replacement for SS racers? That's quite an increase over the factory piece. On the upside, originals should hold their value seeing as how they would be better suited for street/strip use, at least unported ones.

Thanks for the data and effort, Joe.

[KMcCullah]

Nice looking intake Mr Joe. Did it come with the valley cover?

I really like the way they did the push tube holes. They look pretty similar to Jay's intake adaptors.

It looks like it's gonna take some filling in spots to get a nice sexy port match. But it certainly will be a deep breather without much messin'.

[thatdarncat]

I wonder how NHRA will view this as a replacement for SS racers? That's quite an increase over the factory piece. On the upside, originals should hold their value seeing as how they would be better suited for street/strip use, at least unported ones.

Thanks for the data and effort, Joe.

It would be theoretically legal for NHRA Super Stock, NHRA basically allows any intake that fits under the original hood and retains the original configuration, in this case 2-4V carbs inline. NHRA doesn't care about the runner volume size on the intake manifold, just the heads. There would be pretty limited applications for this though - it would have to be a car, like a 427 Galaxie or 427 Fairlane / Comet that came with 2-4V's and a low riser or medium riser style head, or the '67 Shelby 428. The '64 Thunderbolt uses 427 Hi-Riser heads, so I think it would take too much rework for that. The thing is, that rule also allows custom built sheet metal style intakes and I think for any max effort Super Stock car that would still be the way to go. Hopefully Blair let's us know his thoughts.

And yes, thanks Joe for the info.

[jayb]

I really like the way they did the push tube holes. They look pretty similar to Jay's intake adaptors.

I noticed that too; they stole my idea LOL!  Maybe it will be a trend...

[Joe-JDC]

Yes, it has a cover, and is machined for an "O" ring seal like Jay's adapter.  The cover is a simple 3/16" aluminum plate with no engraving. The seal is not continuous, but a rope seal.  I haven't installed mine yet, since I may be doing some additional port work like a very simple gasket match to see how much that affects the flow, and I may bolt it up to my Survival heads that flow 350+cfm to see how it affects them.  Lots of projects in the works, just so many hours in my energy level at my age.  LOL.  Will be interesting to do a back to back with both tunnel wedges on a big cubic inch and decent compression and camshaft.  Headers may become the bottleneck for shocktower cars.   Joe-JDC

[FElony]

Can the airflow be cheated/sped up with small carbs? 450 cfm maybe? How do you get a manifold like this to idle at 800-900?