7M Cylinder Head Flow Numbers

[DEFIANT 7M]

Here are the stock and ported flow numbers of a 7MGE/GTE cylinder head.

Stock:

Intake
lift-flow

.100-77.4 cfm
.150-113.9 cfm
.200-141.4 cfm
.250-162.8 cfm
.300-176 cfm
.350-179.6 cfm
.400-179.6 cfm
.450-180 cfm

Exhaust
lift-flow

.100-60.4 cfm
.150-93 cfm
.200-112.9 cfm
.250-123.2 cfm
.300-127.8 cfm
.350-130.7 cfm
.400-133.2 cfm
.450-133.2 cfm

Fully Ported (valve stems removed to port + bowl work)

Intake
lift-flow

.100-80.4 cfm
.150-122.4 cfm
.200-159.9 cfm
.250-187.8 cfm
.300-202.4 cfm
.350-211.2 cfm

Exhaust
lift-flow

.100-70 cfm
.150-103.4 cfm
.200-121.0 cfm
.250-131.0 cfm
.300-139.4 cfm
.350-144.7 cfm

We stopped @.350 because most regrind cams don't go past this lift.

 

[DEFIANT 7M]

Stock lift is 7.6mm (.300) for a N/A cam, we measured the cams to get our numbers, the duration is 199 @ .050.

 

[Ckanderson]

Coppied to the FAQ section!

 

[DEFIANT 7M]

There are two designs (port designs) of the 7M head. One has been dubbed "Big Port". Not sure of the production years. I have one of these heads from a JDM N/A, the casting number is 12. I had it flow tested to see if there was any differences. To my surprise the numbers where only different by 1-2 cfm up to .350 lift. Past .350 lift that head flows 10 cfm more in stock form than the regular port head in stock form. If there where a cam that had more than .350 lift maybe this head would be something to look at. Hope this information helps answer any questions about the "Big Port" head.

 

[DEFIANT 7M]

Here is something from Dayle@Revolutionary Performance. He is the actual madman behind my insane N/A build up.

I would like to try oversize valves in the head but dealing with the size of the seats, you really can't put that much bigger of a valve in there without changing the seats out which gets expensive in a hurry along with custom valves. I would try something like the size in the 2JZGE head which is about .060 bigger on the intake and exhaust. That is a pretty significant change in size and especially with a low lift cam can make a big difference in airflow. That seat and valve replacement would also allow enough room to really put on a good valve job. A couple years ago we totally rebuilt a 1992 Formula 1 Ferrari V10 and learned a lot of stuff about multi valve engines that is or was not very well known. A big fault of most production heads is the valve seat itself is so narrow you have a difficult time getting the right angles on there for the right width. You only have enough room to make about a .030-.050 bottom cut when you really would get much better results with a much wider bottom cut. Many people mistakenly feel that a radius valve job is the way to go but really just a few carefully chosen angles will perform better in almost every case. The hard part is choosing those angles as different engines like different top and bottom cuts and different backcuts on the valves. The green areas are above the short side radius which should never be brought down. Sometimes it can be laid back a little if you run into port turbulence and it will straighten it back out. I also sort of flatten out the short side radius just a little so instead of being round it is a little flatter until you reach the sides of the bowls.

 

[DEFIANT 7M]

Coppied to the FAQ section!

Okay, kool..

 

[DEFIANT 7M]

Final Flow Numbers
Intake

Lift - Stock CFM - Street Port - Full Race

0.100 - 77.4 - 80.4 - 80.8
0.150 - 113.9 - 122.4 - 121.7
0.200 - 141.4 - 159.9 - 152.6
0.250 - 162.8 - 187.9 - 181.0
0.300 - 176.0 - 202.4 - 201.3
0.350 - 179.6 - 211.2 - 211.8
0.400 - 179.6 - 216.5 - 222.4
0.450 - 180.0 - 220.0 - 231.8
0.500 - 180.0 - 220.0 - 239.1

Exhaust

0.100 - 60.4- 70.0 - 70.0
0.150 - 93.0- 103.4- 108.0
0.200 - 112.9 - 121.0 - 135.2
0.250 - 123.2 - 131.0 - 150.3
0.300 - 127.8 - 139.4 - 163.8
0.350 - 130.7 - 143.1 - 167.6
0.400 - 133.2 - 149.5 - 171.8
0.450 - 133.2 - 155.0 - 174.0
0.500 - 133.0 - 155.0 - 188.0

 

[IJ.]

Big gains on the exhaust side there Allan?

 

[DEFIANT 7M]

Big gains on the exhaust side there Allan?

Yea we picked it up a little bit

 

[IJ.]

Are the headers going to be big enough to keep the reversion dam in place?

 

[DEFIANT 7M]

Here are some pics of the head w/2JZ valves compared to 7M valves.
http://www.villagephotos.com/pubbrowse.asp?folder_id=453937

 

[Idealsupra]

wow...color me impressed allan...

the race port on the intake seemed to hinder cfm flow (for the most part) while on the exhaust side it picked it up extremely well...interesting stuff and thanks BIG TIME for the numbers...this will help me in the near future with a build im doing


keep up all informed about those numbers...

oh and by the way 3inch exhaust on that NA all the way

 

[DEFIANT 7M]

wow...color me impressed allan...

the race port on the intake seemed to hinder cfm flow (for the most part) while on the exhaust side it picked it up extremely well...interesting stuff and thanks BIG TIME for the numbers...this will help me in the near future with a build im doing


keep up all informed about those numbers...

oh and by the way 3inch exhaust on that NA all the way

Hey thanks and no problem LOL 3" exhaust all the way