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Yeah, it's reputation among gearheads but most other people are pretty gullible. They tend to believe most of what they read.

I found an old thread from a couple years ago and nobody really gave a straight answer.

moparts: WATCH "THE AMERICAN MUSCLE CAR TONIGHT"@9:30PM

Why would you say the Hemi has more potential?
True about the reputation. The Hemi has higher flowing intake ports. Does anything else matter? :)

paulie
 

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True about the reputation. The Hemi has higher flowing intake ports. Does anything else matter? :)

paulie
Word my brudda......

Iron 426 hemi flowed 355-ish, could support 750+ hp if all else was right and spun high enough.

TP Ford "only" 310-ish on a good day, for almost 100 hp less

With that being said, spinning 426 inches high enough to be able to use that airflow isn't very streetable.

I would have to guess that hemi in the test was a little bigger than 426 cid and very much not stock.
 

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Word my brudda......

Iron 426 hemi flowed 355-ish, could support 750+ hp if all else was right and spun high enough.

TP Ford "only" 310-ish on a good day, for almost 100 hp less

With that being said, spinning 426 inches high enough to be able to use that airflow isn't very streetable.

I would have to guess that hemi in the test was a little bigger than 426 cid and very much not stock.
The record for a legal Super Stock Hemi is 8.33 sec at 157mph,the record for Super Stock A is 8.78 sec at 153mph held by a 427 Ford Fairlane T-Bolt.To run that fast in either class would need more than 800HP.The 64 427's were Hi-Riser headed engines,so flow numbers do not always equate to more useable HP.A 427 t-bolt won SS/A at Indy this year taking out some hemis along the way! ROY.
 

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Yeah, it's reputation among gearheads but most other people are pretty gullible. They tend to believe most of what they read.

I found an old thread from a couple years ago and nobody really gave a straight answer.

moparts: WATCH "THE AMERICAN MUSCLE CAR TONIGHT"@9:30PM

Why would you say the Hemi has more potential?
Like "harddriven1le" stated towards the end of page 1, why didn't the the hemis run better than 13.40's with 9" slicks and 4.56 gears? (Back in '71 my stock engine 428 CJ Mustang w/ headers 10" MT slicks and 4:30 gears bogged above 5200rpm (usually shifted at 5800) went 13:20's. First time running with the gears. I was pi$$ed so I tore it down to find a cracked head. Never ran it again after that, couldn't afford to get it fixed. Granted the Charger weighed more but I only had 2.09 in/1.65 ex didn't flow even close to the hemi head.
I respect and admire the hemi also but....
 

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Word my brudda......

Iron 426 hemi flowed 355-ish, could support 750+ hp if all else was right and spun high enough.

TP Ford "only" 310-ish on a good day, for almost 100 hp less

With that being said, spinning 426 inches high enough to be able to use that airflow isn't very streetable.

I would have to guess that hemi in the test was a little bigger than 426 cid and very much not stock.
Hey brudda!

I wonder how the 426 Hemi and 427 Tunnel port compare if you measure flow vs cross sectional area? If for instance the Hemi had similar cross sectional area with it's much greater flow then it'd likely be superior in almost any instance, regardless of cubic inches or rpm. If the Hemi has a similar ratio of flow to cross sectional area, then the 427 TP might actually be better for smaller cid or lower rpm. I seem to remember reading that the 427 wedges could compete with the Hemi on shorter tracks.

I don't know the answer, but now I'm curious.....;)

The combustion chamber of the Hemi is a whole other issue. IMO, huge inefficient chambers like that work well if there's a flow gain and if you can run race gas. For lower octane gas the wedge has an advantage here as it can generally run higher compression ratio without detonating. That's one reason the Hemi doesn't do well at the Engine Master's Challenge, again IMO. Officially rambling now.....

paulie
 

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I realize this is pretty unscientific, but I looked at the intake gasket size of the 426 Hemi and the 427 Tunnel Port.

The Hemi is a about 2.00x1.85" with a square shape. The resulting area is about 3.70 square inches.

The 427 TP is about 2.2x2.31 with an almost round shape. Since TP port isn't an exact circle, I estimated it's area by taking 2.25" and got the area of the resulting circle. The area is about 3.97 square inches.

Flow to cross sectional area:

1) 426 Hemi - 355cfm/3.70 sq. in. = 95.9 cfm/sq. in.

2) 427 TP - 310 cfm/3.97 sq. in. = 78.1 cfm/ sq. in.

Just food for thought.

paulie
 

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I don't think ANYTHING came from the factory with tunnel port heads. I believe they were a parts option after the car was purchased. I doubt you could have gotten ahold of them without knowing someone big unless the factory recognised you as a contender in the race circuits. Maybe my history is off, but I don't think that Ford developed the true Hemi head design. I don't remember anything in the 50's from Ford with a Hemi. I do, however, recall a ton of Chrysler products with Hemi's form the early 50's.

As far as I am concerned the Tunnel Port was designed for the Side Oiler 427, which LOOKS similar to any FE, but that is where it ends. Totally different animal that a production FE anything. They were (sideoilers) an option, but good luck getting one back then, as they were in short supply from the get-go. Ask Carrol Shelby, he could not get enough of them for any amount of production of the shelby auto's. Very, very few Cobra's left the Los Angeles facility with true 427's most were 428's. Alot of 427's were transplanted later as they became available.
Hemi engine - Wikipedia, the free encyclopedia

Not that Wikipedia is a trustworthy source of info, but here is a link. The hemispherical chamber has been around since the early 1900's. Radial airplane engines have hemispherical chambers. Chrysler developed a hemi engine for military aviation use in the 1930's. Another link;

ptdoityourself.net - Chrysler Hemi and Combustion Chamber Design
 

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Hemi engine - Wikipedia, the free encyclopedia

Not that Wikipedia is a trustworthy source of info, but here is a link. The hemispherical chamber has been around since the early 1900's. Radial airplane engines have hemispherical chambers. Chrysler developed a hemi engine for military aviation use in the 1930's. Another link;

ptdoityourself.net - Chrysler Hemi and Combustion Chamber Design
the hemi and the 429 ford are in the same class! the 427 ford tunnelport is 3 classes ahead! i have seen numerous 426 hemis fall in defeat to simple 427 low medium and high risers. and as for the 429 ford might as well just start with the 460.
 

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The record for a legal Super Stock Hemi is 8.33 sec at 157mph,the record for Super Stock A is 8.78 sec at 153mph held by a 427 Ford Fairlane T-Bolt.To run that fast in either class would need more than 800HP.The 64 427's were Hi-Riser headed engines,so flow numbers do not always equate to more useable HP.A 427 t-bolt won SS/A at Indy this year taking out some hemis along the way! ROY.
and that fairlane was not a tunnelport
 

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Im calling BS on the 427 TP. You may have been around 427's your whole life, but I've been around both, and I'll tell you now that a properly built BOSS 429 will destroy a 427 TP any day.

The Boss 429 made more power, it was designed specifically for the high RPM's of the Superspeedways.

Huge intake ports dont make the whole motor. You are way wrong in saying the Mopar Hemi is no threat either. You've obviuosly never been anyhere near a good running Hemi.

The 427 TP was a ban-aid fix at best. Im not knocking it for its mechanical abilities, Im telling you that it was a last ditch efort on Fords part to stay competitive with Mopar Hemi's after the 427 Cammer was banned.

Because there was no way in hell that a 427 Medium Riser was going to hang anywhere near a fire breathing Hemi Mopar!!

So Ford quickly came up with the Tunnel Port head and intake setup for the 427 block. But right away, they were already at work on the new Boss 429 Hemi engine for NASCAR.

There is no way that a Tunnel Port cylinder head can move as much air as a Boss Hemi head can....no way in hell.

And more air into and out of an engine means more power, period!!

Also, the 429 Boss did'nt need side oiling because the engineers got the standard oiling correct in the first place.
the 427 tunnel port will smoke any 429 ford or 426 hemi those engines are in the class of good but not great. the 427 tunnel port is in the excellent class! and that band aid sure fixed em. flow means nothing if the whole engine is not built around it the hemi and the 429 ford are very inefficient. might as well just go with a 460!
 

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Enough time has passed that there's a lot of mythology coloring the argument. The Hemi existed in the 1950's and the Hemi of the 50's was not an automatic Ford/Chevy killer. The small block Chevy of the mid 50's seems to have been more than capable of competing with the Mopars. Consider the 57 Corvette with FI turned in performance numbers that were outstanding. Even today there are 283/265 Tri Five Chevys running almost unheard of 1/4 mile times. Pure dragsters not withstanding it is worth asking why Hemis of the era not been dominating the field? The Ford Y Block was the engine that competed against the first generation of Hemis. Not surprisingly the Y more often than not got the short end of the stick. However not all Y blocks as the 1954 Lincoln Road Racers were something of a sure thing in their genre.

But the FE engine was entirely another story and in 1963 the 427 wedge ruled the NASCAR ovals. It is interesting that the Chrysler wedge was so out classed by the Ford 427FE that they needed to reintroduce the Hemi in order to stay competitive. It is equally interesting that the Cammer which arguably is the most potent American V8 ever made was banned and both the Cammer and the Hemi never had a real opportunity to compete on the big Ovals. But the Hemi did get to run and while it dominated at times the FE427 wedge was never hopelessly outclassed. The Tunnel Port almost evened the playing field and that says a lot about the engineering that went into the 427FE. I can remember seeing 427 Fairlanes at the drags and they usually were victorious. In fact the Thunderbolts pretty much beat everything GM and Mopar had to put up against them. So maybe the Hemi had a potential edge but IMHO when a Hemi pilot comes up next to big FE the Hemi is not an automatic sure thing.
 

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Boy is that an understatement! The tunnel port head never came on a production car unless you call the 6 GT40 MKIVs a production car. The heads were over the counter only. C7OE 6049-K. The head is hampered by the "conventional " 427 exhaust port.
The SOHC never ran a Nascar race, it was not approved for competition when presented to Nascar leaving Ford with a few hundred of them which were set to Holman Moody to be sold off.
The tunnel port was Ford's designated replacement as it "fit" into Nascar's rules. They were allowed dual fours and a weight break over the hemi. That allowed the 427 to be competitive. By late '67 Ford set forth on building the ( then named) 429 Nascar engine and it WAS as powerful as the Chrysler hemi. ( the street version was easily out run by a 428CJ Mustang as previously mentioned). The tunnel port head wouldn't ( in the day) go beyond 1,000 hp , where the cammer and Boss were capable of 2,000+ on nitro.
Ford engineers were constantly reworking the tunnel port head to improve it. Port configurations , "air foil" pushrod tubes and a host of other mods are in my SK book listings. IF it were "the answer" it would not have been dropped after two years of use. It was great in it's day but unfortunately time marches on.
The 427 side oiler was a direct result of the SOHC engine program. When the C5AE block patterns were created , they were made so that "top oiler" or "side oiler" configurations could be machined into the casting eliminating the top oiler block patterns. Marine and industrial use 427's got the revised block with top oiler machining and marine engines got brass core plugs
Randy
 
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