Comparison of Mummert Heads to Original Ford Castings

Oldmics (8/18/2010)

Can we get the air flow numbers on Johns new heads and also an air flow number on a set of stock "G" heads for comparison purposes? Oldmics

Here’s what John said awhile back regarding flow numbers on ported iron heads

John Mummert (3/19/2010)

The upper port of almost any Y-Block head can be ported into the 210-215CFM range. The G, -113 and -471 heads can be ported to around 225CFM with 1.94" and 230's with 2.02" for both upper and lower. The problem with the less desirable heads is the lower. I've tried every trick I can think of and most won't reach 200CFM. The lower on the C head is one of the worst. High 190's is the best I've found. The C1AE can be made better with good porting and 1.88" valve,1.94" cut down to 1.88" to avoid spark plug interferrence.

And here’s John talking about flow numbers on the unported and ported aluminum heads.

John Mummert (7/21/2010)

….The first heads sent to Ted flow in the 235 range. Having ported more Y-Block heads than I can count we put most of the tricks in the new castings right out of the box. Granted, some material has to be left around pushrod holes and headbolt holes in case of core shift ect. The out of the box head also needs to work on a 300 cu in street engine. That was the goal. There are some things that can be done in a reasonable amount of time that will increase the flow into the 250-255 CFM range but 270CFM requires non stock port openings and pushing every corner to near the limit. This takes a great deal of time.

At 270CFM the heads will run a 320 inch engine well into the 7000 RPM range. I wouldn't consider this with cast pistons, stock rods or main cap fasteners. That is why I felt that running the EMC heads on the mule engine was not a appropriate test since the redline would need to held well below the potential of the heads. A low compression 320 incher with an antique cam and low redline simply won't show the true potential of the EMC heads.

Doing a search on this site can bring up some other discussions. Here’s a link to get you started.

http://www.y-blocksforever.com/forums/Topic41409-3-1.aspx

Lorena, Texas (South of Waco)

Author	Message
*Hoosier Hurricane*	Posted 15 Years Ago
Supercharged Group: Moderators Last Active: 5 hours ago Posts: 3.7K, Visits: 322.0K	Paul: The angled portion of the exhaust ports (all 4 have them) is one place where you can hit water when porting. The water jacket in that area is there because of the spark plug location. Compare the plug locations of John's and Ford's heads. John doesn't need that angled water jacket casting. By the way, '54 heads had squared ports, they used 14mm plugs instead of 18mm. John - "The Hoosier Hurricane"
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Oldmics	Posted 15 Years Ago
Supercharged Group: Forum Members Last Active: 5 Years Ago Posts: 710, Visits: 78.1K	Can we get the air flow numbers on Johns new heads and also an air flow number on a set of stock "G" heads for comparison purposes? Oldmics
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PF Arcand	Posted 15 Years Ago
Supercharged Group: Forum Members Last Active: Last Year Posts: 3.3K, Visits: 238.8K	Flow on stock & ported "G" heads is available in issue #96 of YBM. And flow numbers on the aluminum heads have been issued here recently, back a bit.. Paul
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Ted	Posted 15 Years Ago
Co-Administrator Group: Administrators Last Active: 15 hours ago Posts: 7.4K, Visits: 205.0K	Oldmics (8/18/2010) Can we get the air flow numbers on Johns new heads and also an air flow number on a set of stock "G" heads for comparison purposes? Oldmics Here’s what John said awhile back regarding flow numbers on ported iron heads John Mummert (3/19/2010) The upper port of almost any Y-Block head can be ported into the 210-215CFM range. The G, -113 and -471 heads can be ported to around 225CFM with 1.94" and 230's with 2.02" for both upper and lower. The problem with the less desirable heads is the lower. I've tried every trick I can think of and most won't reach 200CFM. The lower on the C head is one of the worst. High 190's is the best I've found. The C1AE can be made better with good porting and 1.88" valve,1.94" cut down to 1.88" to avoid spark plug interferrence. And here’s John talking about flow numbers on the unported and ported aluminum heads. John Mummert (7/21/2010) ….The first heads sent to Ted flow in the 235 range. Having ported more Y-Block heads than I can count we put most of the tricks in the new castings right out of the box. Granted, some material has to be left around pushrod holes and headbolt holes in case of core shift ect. The out of the box head also needs to work on a 300 cu in street engine. That was the goal. There are some things that can be done in a reasonable amount of time that will increase the flow into the 250-255 CFM range but 270CFM requires non stock port openings and pushing every corner to near the limit. This takes a great deal of time. At 270CFM the heads will run a 320 inch engine well into the 7000 RPM range. I wouldn't consider this with cast pistons, stock rods or main cap fasteners. That is why I felt that running the EMC heads on the mule engine was not a appropriate test since the redline would need to held well below the potential of the heads. A low compression 320 incher with an antique cam and low redline simply won't show the true potential of the EMC heads. Doing a search on this site can bring up some other discussions. Here’s a link to get you started. http://www.y-blocksforever.com/forums/Topic41409-3-1.aspx Lorena, Texas (South of Waco)
	Reply Quote

Comparison of Mummert Heads to Original Ford Castings

Comparison of Mummert Heads to Original Ford Castings

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