How would a 550 HP 427 FE get any air to make power?

[427LX]

In the typical 1965 Cobra setup shown here.  Amazing they ran as good as they did! Supposed to be an exact recreation of first Shelby 427 Cobra.

[1968galaxie]

With these cars being ~ 2000 lbs even 400 HP would make most people crap their pants at full throttle.
550HP on dyno, perhaps 450 when in the car with exhaust and restrictive inlet design.
Still very fast for most.

[cammerfe]

The plate with the pierced holes in the front of the scoop does not go with the 'bathtub' on the engine. It WOULD make a difference.

KS

[machoneman]

Yes, the plate with the holes may be OEM Shelby but few were seen with it. Race cobra pics of yore show only open scoops. Btw, the bigger issue with Cobras is the 'cartridges" as I call them inside those swoopy looking side pipes. Tests I've seen here on the Web showed huge hp losses with this setup compared to pipes where the cartridges were left out. Very loud of course but...

[427LX]

Wonder if the drop base Chevy 427 air filter assembly would have fit?

[cleandan]

I think this showcases some of the perceived restrictions for making power because it is often the sum total of the finished machine rather than a single part or aspect.

Take the Cobra Roadster race car as the example.
Even with its bird catcher plate in the scoop, the amount of air that holed plate will allow still outperforms the capability of the carb installed.

This means the carb will not be starved for air because the carb can not move more air than the  restrictive holed spacer can always provide.

Now factor into the mix the forced air being pushed into the scoop when at speed and the "restriction" becomes even less of an issue.

Next factor into the mix the idea that the carbs max airflow capability will only be used a portion of the time. The rest of the time the carb, while maybe at full throttle, is not being asked to flow max air until the engine is at full rpm and trying to use full carb potential.
All the time between max airflow, which is likely anything under 5,500 rpm, the carb is not actually using its full capacity because the engine is not trying to move that much air.

Lastly the scoop is not sealed to the hood scoop so the scoop is not providing the only air the engine will use.
That scoop is only part of the air available to the engine because, even with the turkey pan, there is air from all around that pan being sucked in from under the hood if needed.

The biggest restriction in this instance is the small Stellings and Hellings air filter, which have been proven to flow enough to make good power.

As in most instances you can make improvements to allow for more potential airflow, but until you can use that potential it remains potential, rather than required.

[cleandan]

Yes, the plate with the holes may be OEM Shelby but few were seen with it. Race cobra pics of yore show only open scoops. Btw, the bigger issue with Cobras is the 'cartridges" as I call them inside those swoopy looking side pipes. Tests I've seen here on the Web showed huge hp losses with this setup compared to pipes where the cartridges were left out. Very loud of course but...

The vast majority of the side pipes on Cobras are quite restrictive.
I have worked on quite a number of them and when removed, or cut open, it is easy to see what is actually there.

While sometimes there are good performance mufflers lurking to burn your calf, most of them are literally a glasspack muffler swedged into the larger pipe.
When cut at the entrance or exit you can clearly see the muffler stuffed into the outer pipe.

I built a jig for my 40 ton press to extract the glasspack from the outer casing just to see how things work out......Some cuttin' and weldin' and paintin' and soon things looked the same on the outside, but they were unrestricted on the inside.
I did this with a side pipe system that got completely removed to make way for another system so I had the parts to play with.
The non-muffled side pipes are LOUD, real loud, but sound pretty good because the 4"+ diameter pipe gives a tone lowering effect.....but it is too loud for 99% of the instances.

Anyway, yes, those side pipes may look big on the outside but they often have a 2", sometimes smaller,  pipe on the inside along with a HUGE wall to hit as the gasses enter the muffler inlet side.

[Falcon67]

I'd be willing to bet that holed plate adds so much turbulence that it's more restriction than it looks.  Bet the air at speed just piles up in front of it more than going through it.  If that was my car, you'd find that plate somewhere in the "miscellaneous" tool box drawer,

[gregaba]

All three of my dad's cobra's he raced in the 60's had an open scoop and no sidepipe's or air filter.
Greg

[StarlinerRon]

That scoop is too low for much of a ram effect. You have to get above the boundary layer for much pressure to happen. It probably helped cool off the engine compartment though.

Ron.

[HTM101]

I've owned a replica 427 Cobra for 28 years.  The 1st side oiler I installed in 1994 had a single Stellings air filter on a 750 Holley and the side pipes were 2.5" internal diameter.  I remember thinking the car was fast, but I actually expected it should have been faster than it was.

Step forward to present day, a different engine and a lot of tweaks to achieve more air filter surface area.  I had custom carb base plates made, used  1/4" phenolic spacers instead of 1/2", re-shaped the hood opening beneath the scoop to allow for positioning the 9" diameter x 2.75" tall filters.  I raised the rear of the hood 7/16" to provide more air filter clearance and let some engine bay heat escape.

The side pipes now have a 3" inner diameter muffler, that's not much of a muffler.  I register about 94 db sound level at idle with the meter laying in my lap.  I wear ear plugs.

Seems like there's a lot more horsepower getting to the pavement.

[482supersnake]

Look up pictures of Bruce Camberns Cobra. He built a different style carb pan and used a flat K &N style filter sealed to the hood.

[HTM101]

Look up pictures of Bruce Camberns Cobra. He built a different style carb pan and used a flat K &N style filter sealed to the hood.

He has a very intensely engineered and modified Cobra that's well sorted.  My taste favors the more original flavor.

[PaulProe]

Those 'scoop plates' were common to the FIA cobra's that used Weber carburetors. I'm told they were used to balance the flow into the carbs since flow near the scoop opening was different than that at the rear of the engine. I can see how airflow into the horns could differ between the front and rear of the engine.

I don't doubt that Peter Klute (Legendary Motors) did his research. Maybe he can comment why the plate? The first 427 was a conglomeration of 289 parts, maybe a left-over from other vehicles?

The plates were not used on Comp or S/C cars, to my knowledge.